api: show example for platform specific application trait

Because we don't want to force all methods on `VideoModeHandle` to return `Option`, we decided to remove the already incomplete support in Android for both types.

.cargo/config.toml

@@ -2,5 +2,8 @@
 #
 # Note that these flags are (intentionally) not included when building from the downloaded crate.
 [build]
-rustflags = ["--cfg=unreleased_changelogs"]
 rustdocflags = ["--cfg=unreleased_changelogs"]
+rustflags = ["--cfg=unreleased_changelogs"]
+
+[target.wasm32-unknown-unknown]
+runner = "wasm-bindgen-test-runner"

.git-blame-ignore-revs

@@ -2,3 +2,7 @@
 
 # chore(rustfmt): use nightly
 7b0c7b6cb2c62767ca0c73c857b299883f55a883
+# Rustfmt: use `group_imports`
+2665c120981af548433645c6383b3580dd8f8fc4
+# Use Taplo for TOML formatting
+3398ebe467c43ccfd91916c5b81ff3c68f598556

.github/CODEOWNERS

@@ -1,10 +1,11 @@
 # Android
-/src/platform/android.rs            @msiglreith @MarijnS95
-/src/platform_impl/android          @msiglreith @MarijnS95
+/src/platform/android.rs            @MarijnS95
+/src/platform_impl/android          @MarijnS95
 
-# iOS
+# Apple (AppKit + UIKit)
 /src/platform/ios.rs                @madsmtm
-/src/platform_impl/ios              @madsmtm
+/src/platform/macos.rs              @madsmtm
+/src/platform_impl/apple            @madsmtm
 
 # Unix
 /src/platform_impl/linux/mod.rs     @kchibisov
@@ -17,17 +18,13 @@
 /src/platform/x11.rs                @kchibisov @notgull
 /src/platform_impl/linux/x11        @kchibisov @notgull
 
-# macOS
-/src/platform/macos.rs              @madsmtm
-/src/platform_impl/macos            @madsmtm
-
 # Web
 /src/platform/web.rs                @daxpedda
 /src/platform_impl/web              @daxpedda
 
 # Windows
-/src/platform/windows.rs            @msiglreith
-/src/platform_impl/windows          @msiglreith
+/src/platform/windows.rs            @notgull
+/src/platform_impl/windows          @notgull
 
 # Orbital (Redox OS)
 /src/platform/orbital.rs            @jackpot51

.github/ISSUE_TEMPLATE/bug_web.yml

@@ -1,5 +1,5 @@
 name: Web bug
-description: Create a web-specific bug report
+description: Create a Web-specific bug report
 labels:
   - B - bug
   - DS - web

.github/dependabot.yaml

@@ -0,0 +1,22 @@
+version: 2
+
+updates:
+  - package-ecosystem: github-actions
+    directory: /
+    schedule:
+        interval: daily
+    groups:
+        github-actions:
+            patterns:
+                - "*"
+
+  - package-ecosystem: npm
+    directory: src/platform_impl/web/script
+    schedule:
+        interval: daily
+    groups:
+        github-actions:
+            patterns:
+                - '*'
+    labels:
+        - "DS - web"

.github/workflows/ci.yml

@@ -10,19 +10,32 @@ jobs:
     name: Check formatting
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v4
+    - uses: taiki-e/checkout-action@v1
     - uses: dtolnay/rust-toolchain@nightly
       with:
         components: rustfmt
     - name: Check Formatting
       run: cargo fmt -- --check
 
+  taplo:
+    name: Taplo
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: taiki-e/checkout-action@v1
+      - name: Install Taplo
+        uses: taiki-e/install-action@v2
+        with:
+          tool: taplo-cli
+      - name: Run Taplo
+        run: taplo fmt --check
+
   typos:
     name: Check for typos
     runs-on: ubuntu-latest
     timeout-minutes: 30
     steps:
-      - uses: actions/checkout@v4
+      - uses: taiki-e/checkout-action@v1
       - uses: taiki-e/install-action@v2
         with:
           tool: typos-cli
@@ -42,7 +55,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        toolchain: [stable, nightly, '1.70.0']
+        toolchain: [stable, nightly, '1.73']
         platform:
           # Note: Make sure that we test all the `docs.rs` targets defined in Cargo.toml!
           - { name: 'Windows 64bit MSVC', target: x86_64-pc-windows-msvc,   os: windows-latest,  }
@@ -58,22 +71,31 @@ jobs:
           - { name: 'macOS',              target: x86_64-apple-darwin,      os: macos-latest,    }
           - { name: 'iOS x86_64',         target: x86_64-apple-ios,         os: macos-latest,    }
           - { name: 'iOS Aarch64',        target: aarch64-apple-ios,        os: macos-latest,    }
-          - { name: 'web',                target: wasm32-unknown-unknown,   os: ubuntu-latest,   }
+          - { name: 'Web',                target: wasm32-unknown-unknown,   os: ubuntu-latest,   }
         exclude:
+          # Web on nightly needs extra arguments
+          - toolchain: nightly
+            platform: { name: 'Web', target: wasm32-unknown-unknown, os: ubuntu-latest }
           # Android is tested on stable-3
-          - toolchain: '1.70.0'
+          - toolchain: '1.73'
             platform: { name: 'Android', target: aarch64-linux-android, os: ubuntu-latest, options: '--package=winit --features=android-native-activity', cmd: 'apk --' }
+          # Redox OS doesn't follow MSRV
+          - toolchain: '1.73'
+            platform: { name: 'Redox OS', target: x86_64-unknown-redox, os: ubuntu-latest }
         include:
-          - toolchain: '1.70.0'
+          - toolchain: '1.73'
             platform: { name: 'Android', target: aarch64-linux-android, os: ubuntu-latest, options: '--package=winit --features=android-native-activity', cmd: 'apk --' }
+          - toolchain: 'nightly'
+            platform: { name: 'Web', target: wasm32-unknown-unknown, os: ubuntu-latest, test-options: -Zdoctest-xcompile }
           - toolchain: 'nightly'
             platform: {
-              name:       'web Atomic',
-              target:     wasm32-unknown-unknown,
-              os:         ubuntu-latest,
-              options:    '-Zbuild-std=panic_abort,std',
-              rustflags:  '-Ctarget-feature=+atomics,+bulk-memory',
-              components: rust-src,
+              name:         'Web Atomic',
+              target:       wasm32-unknown-unknown,
+              os:           ubuntu-latest,
+              options:      '-Zbuild-std=panic_abort,std',
+              test-options: -Zdoctest-xcompile,
+              rustflags:    '-Ctarget-feature=+atomics,+bulk-memory',
+              components:   rust-src,
             }
 
     env:
@@ -83,19 +105,21 @@ jobs:
 
       # Faster compilation and error on warnings
       RUSTFLAGS: '--codegen=debuginfo=0 --deny=warnings ${{ matrix.platform.rustflags }}'
+      RUSTDOCFLAGS: ${{ matrix.platform.rustflags }}
 
       OPTIONS: --target=${{ matrix.platform.target }} ${{ matrix.platform.options }}
+      TEST_OPTIONS: ${{ matrix.platform.test-options }}
       CMD: ${{ matrix.platform.cmd }}
 
     steps:
-    - uses: actions/checkout@v4
+    - uses: taiki-e/checkout-action@v1
 
     - name: Restore cache of cargo folder
       # We use `restore` and later `save`, so that we can create the key after
       # the cache has been downloaded.
       #
       # This could be avoided if we added Cargo.lock to the repository.
-      uses: actions/cache/restore@v3
+      uses: actions/cache/restore@v4
       with:
         # https://doc.rust-lang.org/cargo/guide/cargo-home.html#caching-the-cargo-home-in-ci
         path: |
@@ -116,7 +140,7 @@ jobs:
     - name: Cache cargo-apk
       if: contains(matrix.platform.target, 'android')
       id: cargo-apk-cache
-      uses: actions/cache@v3
+      uses: actions/cache@v4
       with:
         path: ~/.cargo/bin/cargo-apk
         # Change this key if we update the required cargo-apk version
@@ -131,6 +155,11 @@ jobs:
       if: contains(matrix.platform.target, 'android') && (steps.cargo-apk-cache.outputs.cache-hit != 'true')
       run: cargo install cargo-apk --version=^0.9.7 --locked
 
+    - uses: taiki-e/cache-cargo-install-action@v2
+      if: contains(matrix.platform.target, 'wasm32') && matrix.toolchain == 'nightly'
+      with:
+        tool: wasm-bindgen-cli
+
     - uses: dtolnay/rust-toolchain@master
       with:
         toolchain: ${{ matrix.toolchain }}${{ matrix.platform.host }}
@@ -149,52 +178,52 @@ jobs:
     - name: Test dpi crate
       if: >
         contains(matrix.platform.name, 'Linux 64bit') &&
-        matrix.toolchain != '1.70.0'
+        matrix.toolchain != '1.73'
       run: cargo test -p dpi
 
     - name: Build tests
       if: >
         !contains(matrix.platform.target, 'redox') &&
-        matrix.toolchain != '1.70.0'
+        matrix.toolchain != '1.73'
       run: cargo $CMD test --no-run $OPTIONS
 
     - name: Run tests
       if: >
         !contains(matrix.platform.target, 'android') &&
         !contains(matrix.platform.target, 'ios') &&
-        !contains(matrix.platform.target, 'wasm32') &&
+        (!contains(matrix.platform.target, 'wasm32') || matrix.toolchain == 'nightly') &&
         !contains(matrix.platform.target, 'redox') &&
-        matrix.toolchain != '1.70.0'
+        matrix.toolchain != '1.73'
       run: cargo $CMD test $OPTIONS
 
     - name: Lint with clippy
       if: (matrix.toolchain == 'stable') && !contains(matrix.platform.options, '--no-default-features')
-      run: cargo clippy --all-targets $OPTIONS -- -Dwarnings
+      run: cargo clippy --all-targets $OPTIONS $TEST_OPTIONS -- -Dwarnings
 
     - name: Build tests with serde enabled
       if: >
         !contains(matrix.platform.target, 'redox') &&
-        matrix.toolchain != '1.70.0'
-      run: cargo $CMD test --no-run $OPTIONS --features serde
+        matrix.toolchain != '1.73'
+      run: cargo $CMD test --no-run $OPTIONS $TEST_OPTIONS --features serde
 
     - name: Run tests with serde enabled
       if: >
         !contains(matrix.platform.target, 'android') &&
         !contains(matrix.platform.target, 'ios') &&
-        !contains(matrix.platform.target, 'wasm32') &&
+        (!contains(matrix.platform.target, 'wasm32') || matrix.toolchain == 'nightly') &&
         !contains(matrix.platform.target, 'redox') &&
-        matrix.toolchain != '1.70.0'
-      run: cargo $CMD test $OPTIONS --features serde
+        matrix.toolchain != '1.73'
+      run: cargo $CMD test $OPTIONS $TEST_OPTIONS --features serde
 
     - name: Check docs.rs documentation
       if: matrix.toolchain == 'nightly'
-      run: cargo doc --no-deps $OPTIONS --features=rwh_04,rwh_05,rwh_06,serde,mint,android-native-activity
+      run: cargo doc --no-deps $OPTIONS --features=serde,mint,android-native-activity
       env:
         RUSTDOCFLAGS: '--deny=warnings ${{ matrix.platform.rustflags }} --cfg=docsrs --cfg=unreleased_changelogs'
 
     # See restore step above
     - name: Save cache of cargo folder
-      uses: actions/cache/save@v3
+      uses: actions/cache/save@v4
       with:
         path: |
           ~/.cargo/registry/index/
@@ -216,13 +245,47 @@ jobs:
           - { name: 'Linux', target: x86_64-unknown-linux-gnu }
           - { name: 'macOS', target: x86_64-apple-darwin }
           - { name: 'Redox OS', target: x86_64-unknown-redox }
-          - { name: 'web', target: wasm32-unknown-unknown }
+          - { name: 'Web', target: wasm32-unknown-unknown }
           - { name: 'Windows', target: x86_64-pc-windows-gnu }
 
     steps:
-    - uses: actions/checkout@v4
-    - uses: EmbarkStudios/cargo-deny-action@v1
+    - uses: taiki-e/checkout-action@v1
+    - uses: EmbarkStudios/cargo-deny-action@v2
       with:
         command: check
         log-level: error
         arguments: --all-features --target ${{ matrix.platform.target }}
+
+  eslint:
+    name: ESLint
+
+    runs-on: ubuntu-latest
+    defaults:
+      run:
+        working-directory: ./src/platform_impl/web/script
+
+    steps:
+      - uses: taiki-e/checkout-action@v1
+      - name: Setup NPM
+        run: npm install
+      - name: Run ESLint
+        run: npx eslint
+
+  swc:
+    name: Minimize JavaScript
+
+    runs-on: ubuntu-latest
+    defaults:
+      run:
+        working-directory: ./src/platform_impl/web/script
+
+    steps:
+      - uses: taiki-e/checkout-action@v1
+      - name: Install SWC
+        run: sudo npm i -g @swc/cli
+      - name: Run SWC
+        run: |
+          swc . --ignore node_modules,**/*.d.ts --only **/*.ts -d . --out-file-extension min.js
+      - name: Check for diff
+        run: |
+          [[ -z $(git status -s) ]]

.github/workflows/docs.yml

@@ -29,10 +29,10 @@ jobs:
         env:
           RUSTDOCFLAGS: --crate-version master --cfg=docsrs --cfg=unreleased_changelogs
         run: |
-          cargo doc --no-deps -Z rustdoc-map -Z rustdoc-scrape-examples --features=rwh_04,rwh_05,rwh_06,serde,mint,android-native-activity
+          cargo doc --no-deps -Z rustdoc-map -Z rustdoc-scrape-examples --features=serde,mint,android-native-activity
 
       - name: Setup Pages
-        uses: actions/configure-pages@v4
+        uses: actions/configure-pages@v5
 
       - name: Fix permissions
         run: |

.gitignore

@@ -3,8 +3,8 @@ target/
 rls/
 .vscode/
 *~
-*.wasm
-*.ts
-*.js
 #*#
 .DS_Store
+# NPM package used to run ESLint.
+/src/platform_impl/web/script/node_modules
+/src/platform_impl/web/script/package-lock.json

Cargo.toml

@@ -1,25 +1,30 @@
 [package]
-name = "winit"
-version = "0.30.0"
-authors = [
-    "The winit contributors",
-    "Pierre Krieger <pierre.krieger1708@gmail.com>",
-]
-description = "Cross-platform window creation library."
-keywords = ["windowing"]
-readme = "README.md"
-documentation = "https://docs.rs/winit"
+authors = ["The winit contributors", "Pierre Krieger <pierre.krieger1708@gmail.com>"]
 categories = ["gui"]
-rust-version.workspace = true
-repository.workspace = true
-license.workspace = true
+description = "Cross-platform window creation library."
+documentation = "https://docs.rs/winit"
 edition.workspace = true
-exclude = ["/.cargo"]
+include = [
+    "/build.rs",
+    "/docs",
+    "/examples",
+    "/FEATURES.md",
+    "/LICENSE",
+    "/src",
+    "!/src/platform_impl/web/script",
+    "/src/platform_impl/web/script/**/*.min.js",
+    "/tests",
+]
+keywords = ["windowing"]
+license.workspace = true
+name = "winit"
+readme = "README.md"
+repository.workspace = true
+rust-version.workspace = true
+version = "0.30.4"
 
 [package.metadata.docs.rs]
 features = [
-    "rwh_04",
-    "rwh_05",
     "rwh_06",
     "serde",
     "mint",
@@ -27,6 +32,7 @@ features = [
     "android-native-activity",
 ]
 # These are all tested in CI
+rustdoc-args = ["--cfg", "docsrs"]
 targets = [
     # Windows
     "i686-pc-windows-msvc",
@@ -43,12 +49,15 @@ targets = [
     # Web
     "wasm32-unknown-unknown",
 ]
-rustdoc-args = ["--cfg", "docsrs"]
 
 # Features are documented in either `lib.rs` or under `winit::platform`.
 [features]
+android-game-activity = ["android-activity/game-activity"]
+android-native-activity = ["android-activity/native-activity"]
 default = ["rwh_06", "x11", "wayland", "wayland-dlopen", "wayland-csd-adwaita"]
-x11 = ["x11-dl", "bytemuck", "percent-encoding", "xkbcommon-dl/x11", "x11rb"]
+mint = ["dpi/mint"]
+rwh_06 = ["dep:rwh_06", "ndk/rwh_06"]
+serde = ["dep:serde", "cursor-icon/serde", "smol_str/serde", "dpi/serde", "bitflags/serde"]
 wayland = [
     "wayland-client",
     "wayland-backend",
@@ -58,41 +67,28 @@ wayland = [
     "ahash",
     "memmap2",
 ]
-wayland-dlopen = ["wayland-backend/dlopen"]
 wayland-csd-adwaita = ["sctk-adwaita", "sctk-adwaita/ab_glyph"]
 wayland-csd-adwaita-crossfont = ["sctk-adwaita", "sctk-adwaita/crossfont"]
 wayland-csd-adwaita-notitle = ["sctk-adwaita"]
-android-native-activity = ["android-activity/native-activity"]
-android-game-activity = ["android-activity/game-activity"]
-serde = ["dep:serde", "cursor-icon/serde", "smol_str/serde", "dpi/serde"]
-mint = ["dpi/mint"]
-rwh_04 = ["dep:rwh_04", "ndk/rwh_04"]
-rwh_05 = ["dep:rwh_05", "ndk/rwh_05"]
-rwh_06 = ["dep:rwh_06", "ndk/rwh_06"]
+wayland-dlopen = ["wayland-backend/dlopen"]
+x11 = ["x11-dl", "bytemuck", "percent-encoding", "xkbcommon-dl/x11", "x11rb"]
 
 [build-dependencies]
-cfg_aliases = "0.2.0"
+cfg_aliases = "0.2.1"
 
 [dependencies]
 bitflags = "2"
 cursor-icon = "1.1.0"
 dpi = { version = "0.1.1", path = "dpi" }
-rwh_04 = { package = "raw-window-handle", version = "0.4", optional = true }
-rwh_05 = { package = "raw-window-handle", version = "0.5.2", features = [
-    "std",
-], optional = true }
-rwh_06 = { package = "raw-window-handle", version = "0.6", features = [
-    "std",
-], optional = true }
+rwh_06 = { package = "raw-window-handle", version = "0.6", features = ["std"], optional = true }
 serde = { workspace = true, optional = true }
 smol_str = "0.2.0"
-tracing = { version = "0.1.40", default_features = false }
+tracing = { version = "0.1.40", default-features = false }
 
 [dev-dependencies]
 image = { version = "0.25.0", default-features = false, features = ["png"] }
-tracing = { version = "0.1.40", default_features = false, features = ["log"] }
+tracing = { version = "0.1.40", default-features = false, features = ["log"] }
 tracing-subscriber = { version = "0.3.18", features = ["env-filter"] }
-winit = { path = ".", features = ["rwh_05"] }
 
 [target.'cfg(not(any(target_os = "android", target_os = "ios")))'.dev-dependencies]
 softbuffer = { version = "0.4.0", default-features = false, features = [
@@ -102,41 +98,26 @@ softbuffer = { version = "0.4.0", default-features = false, features = [
     "wayland-dlopen",
 ] }
 
+# Android
 [target.'cfg(target_os = "android")'.dependencies]
 android-activity = "0.6.0"
 ndk = { version = "0.9.0", default-features = false }
 
-[target.'cfg(any(target_os = "ios", target_os = "macos"))'.dependencies]
+# AppKit or UIKit
+[target.'cfg(target_vendor = "apple")'.dependencies]
 core-foundation = "0.9.3"
-objc2 = "0.5.1"
+objc2 = "0.5.2"
 
+# AppKit
 [target.'cfg(target_os = "macos")'.dependencies]
+block2 = "0.5.1"
 core-graphics = "0.23.1"
-
-[target.'cfg(target_os = "macos")'.dependencies.objc2-foundation]
-version = "0.2.0"
-features = [
-    "dispatch",
-    "NSArray",
-    "NSAttributedString",
-    "NSData",
-    "NSDictionary",
-    "NSEnumerator",
-    "NSObjCRuntime",
-    "NSString",
-    "NSPathUtilities",
-    "NSProcessInfo",
-    "NSThread",
-    "NSValue",
-]
-
-[target.'cfg(target_os = "macos")'.dependencies.objc2-app-kit]
-version = "0.2.0"
-features = [
+objc2-app-kit = { version = "0.2.2", features = [
     "NSAppearance",
     "NSApplication",
     "NSBitmapImageRep",
     "NSButton",
+    "NSColor",
     "NSControl",
     "NSCursor",
     "NSDragging",
@@ -158,11 +139,30 @@ features = [
     "NSWindow",
     "NSWindowScripting",
     "NSWindowTabGroup",
-]
+] }
+objc2-foundation = { version = "0.2.2", features = [
+    "block2",
+    "dispatch",
+    "NSArray",
+    "NSAttributedString",
+    "NSData",
+    "NSDictionary",
+    "NSDistributedNotificationCenter",
+    "NSEnumerator",
+    "NSKeyValueObserving",
+    "NSNotification",
+    "NSObjCRuntime",
+    "NSPathUtilities",
+    "NSProcessInfo",
+    "NSRunLoop",
+    "NSString",
+    "NSThread",
+    "NSValue",
+] }
 
-[target.'cfg(target_os = "ios")'.dependencies.objc2-foundation]
-version = "0.2.0"
-features = [
+# UIKit
+[target.'cfg(all(target_vendor = "apple", not(target_os = "macos")))'.dependencies]
+objc2-foundation = { version = "0.2.2", features = [
     "dispatch",
     "NSArray",
     "NSEnumerator",
@@ -172,14 +172,32 @@ features = [
     "NSProcessInfo",
     "NSThread",
     "NSSet",
-]
+] }
+objc2-ui-kit = { version = "0.2.2", features = [
+    "UIApplication",
+    "UIDevice",
+    "UIEvent",
+    "UIGeometry",
+    "UIGestureRecognizer",
+    "UIOrientation",
+    "UIPanGestureRecognizer",
+    "UIPinchGestureRecognizer",
+    "UIResponder",
+    "UIRotationGestureRecognizer",
+    "UIScreen",
+    "UIScreenMode",
+    "UITapGestureRecognizer",
+    "UITouch",
+    "UITraitCollection",
+    "UIView",
+    "UIViewController",
+    "UIWindow",
+] }
 
+# Windows
 [target.'cfg(target_os = "windows")'.dependencies]
 unicode-segmentation = "1.7.1"
-
-[target.'cfg(target_os = "windows")'.dependencies.windows-sys]
-version = "0.52.0"
-features = [
+windows-sys = { version = "0.52.0", features = [
     "Win32_Devices_HumanInterfaceDevice",
     "Win32_Foundation",
     "Win32_Globalization",
@@ -204,12 +222,13 @@ features = [
     "Win32_UI_Shell",
     "Win32_UI_TextServices",
     "Win32_UI_WindowsAndMessaging",
-]
+] }
 
-[target.'cfg(all(unix, not(any(target_os = "redox", target_family = "wasm", target_os = "android", target_os = "ios", target_os = "macos"))))'.dependencies]
+# Linux
+[target.'cfg(all(unix, not(any(target_os = "redox", target_family = "wasm", target_os = "android", target_vendor = "apple"))))'.dependencies]
 ahash = { version = "0.8.7", features = ["no-rng"], optional = true }
 bytemuck = { version = "1.13.1", default-features = false, optional = true }
-calloop = "0.12.3"
+calloop = "0.13.0"
 libc = "0.2.64"
 memmap2 = { version = "0.9.0", optional = true }
 percent-encoding = { version = "2.0", optional = true }
@@ -219,86 +238,91 @@ rustix = { version = "0.38.4", default-features = false, features = [
     "thread",
     "process",
 ] }
-sctk = { package = "smithay-client-toolkit", version = "0.18.0", default-features = false, features = [
+sctk = { package = "smithay-client-toolkit", version = "0.19.2", default-features = false, features = [
     "calloop",
 ], optional = true }
-sctk-adwaita = { version = "0.9.0", default_features = false, optional = true }
-wayland-backend = { version = "0.3.0", default_features = false, features = [
+sctk-adwaita = { version = "0.10.1", default-features = false, optional = true }
+wayland-backend = { version = "0.3.5", default-features = false, features = [
     "client_system",
 ], optional = true }
-wayland-client = { version = "0.31.1", optional = true }
-wayland-protocols = { version = "0.31.0", features = [
-    "staging",
-], optional = true }
-wayland-protocols-plasma = { version = "0.2.0", features = [
-    "client",
-], optional = true }
+wayland-client = { version = "0.31.4", optional = true }
+wayland-protocols = { version = "0.32.2", features = ["staging"], optional = true }
+wayland-protocols-plasma = { version = "0.3.2", features = ["client"], optional = true }
 x11-dl = { version = "2.19.1", optional = true }
 x11rb = { version = "0.13.0", default-features = false, features = [
     "allow-unsafe-code",
     "dl-libxcb",
     "randr",
     "resource_manager",
+    "sync",
     "xinput",
     "xkb",
 ], optional = true }
 xkbcommon-dl = "0.4.2"
 
+# Orbital
 [target.'cfg(target_os = "redox")'.dependencies]
 orbclient = { version = "0.3.47", default-features = false }
 redox_syscall = "0.4.1"
 
-[target.'cfg(target_family = "wasm")'.dependencies.web_sys]
-package = "web-sys"
-version = "0.3.64"
-features = [
-    'AbortController',
-    'AbortSignal',
-    'Blob',
-    'console',
-    'CssStyleDeclaration',
-    'Document',
-    'DomException',
-    'DomRect',
-    'DomRectReadOnly',
-    'Element',
-    'Event',
-    'EventTarget',
-    'FocusEvent',
-    'HtmlCanvasElement',
-    'HtmlElement',
-    'HtmlImageElement',
-    'ImageBitmap',
-    'ImageBitmapOptions',
-    'ImageBitmapRenderingContext',
-    'ImageData',
-    'IntersectionObserver',
-    'IntersectionObserverEntry',
-    'KeyboardEvent',
-    'MediaQueryList',
-    'MessageChannel',
-    'MessagePort',
-    'Node',
-    'PageTransitionEvent',
-    'PointerEvent',
-    'PremultiplyAlpha',
-    'ResizeObserver',
-    'ResizeObserverBoxOptions',
-    'ResizeObserverEntry',
-    'ResizeObserverOptions',
-    'ResizeObserverSize',
-    'VisibilityState',
-    'Window',
-    'WheelEvent',
-    'Url',
-]
-
+# Web
 [target.'cfg(target_family = "wasm")'.dependencies]
 js-sys = "0.3.64"
 pin-project = "1"
 wasm-bindgen = "0.2"
 wasm-bindgen-futures = "0.4"
 web-time = "1"
+web_sys = { package = "web-sys", version = "0.3.64", features = [
+    "AbortController",
+    "AbortSignal",
+    "Blob",
+    "BlobPropertyBag",
+    "console",
+    "CssStyleDeclaration",
+    "Document",
+    "DomException",
+    "DomRect",
+    "DomRectReadOnly",
+    "Element",
+    "Event",
+    "EventTarget",
+    "FocusEvent",
+    "HtmlCanvasElement",
+    "HtmlElement",
+    "HtmlImageElement",
+    "ImageBitmap",
+    "ImageBitmapOptions",
+    "ImageBitmapRenderingContext",
+    "ImageData",
+    "IntersectionObserver",
+    "IntersectionObserverEntry",
+    "KeyboardEvent",
+    "MediaQueryList",
+    "MessageChannel",
+    "MessagePort",
+    "Navigator",
+    "Node",
+    "OrientationLockType",
+    "OrientationType",
+    "PageTransitionEvent",
+    "Permissions",
+    "PermissionState",
+    "PermissionStatus",
+    "PointerEvent",
+    "PremultiplyAlpha",
+    "ResizeObserver",
+    "ResizeObserverBoxOptions",
+    "ResizeObserverEntry",
+    "ResizeObserverOptions",
+    "ResizeObserverSize",
+    "Screen",
+    "ScreenOrientation",
+    "Url",
+    "VisibilityState",
+    "WheelEvent",
+    "Window",
+    "Worker",
+] }
 
 [target.'cfg(all(target_family = "wasm", target_feature = "atomics"))'.dependencies]
 atomic-waker = "1"
@@ -307,21 +331,27 @@ concurrent-queue = { version = "2", default-features = false }
 [target.'cfg(target_family = "wasm")'.dev-dependencies]
 console_error_panic_hook = "0.1"
 tracing-web = "0.1"
+wasm-bindgen-test = "0.3"
 
 [[example]]
 doc-scrape-examples = true
 name = "window"
+required-features = ["rwh_06"]
+
+[[example]]
+name = "child_window"
+required-features = ["rwh_06"]
 
 [workspace]
-resolver = "2"
 members = ["dpi"]
+resolver = "2"
 
 [workspace.package]
-rust-version = "1.70.0"
-repository = "https://github.com/rust-windowing/winit"
-license = "Apache-2.0"
 edition = "2021"
+license = "Apache-2.0"
+repository = "https://github.com/rust-windowing/winit"
+rust-version = "1.73"
 
 [workspace.dependencies]
-serde = { version = "1", features = ["serde_derive"] }
 mint = "0.5.6"
+serde = { version = "1", features = ["serde_derive"] }

FEATURES.md

@@ -154,7 +154,6 @@ If your PR makes notable changes to Winit's features, please update this section
 * Home indicator visibility
 * Status bar visibility and style
 * Deferring system gestures
-* Getting the device idiom
 * Getting the preferred video mode
 
 ### Web

README.md

@@ -8,7 +8,7 @@
 
 ```toml
 [dependencies]
-winit = "0.30.0"
+winit = "0.30.4"
 ```
 
 ## [Documentation](https://docs.rs/winit)
@@ -19,7 +19,7 @@ For features _outside_ the scope of winit, see [Are we GUI Yet?](https://arewegu
 
 ## Contact Us
 
-Join us in our [![Matrix](https://img.shields.io/badge/Matrix-%23rust--windowing%3Amatrix.org-blueviolet.svg)](https://matrix.to/#/#rust-windowing:matrix.org) room. If you don't get an answer there, try [![Libera.Chat](https://img.shields.io/badge/libera.chat-%23winit-red.svg)](https://web.libera.chat/#winit).
+Join us in our [![Matrix](https://img.shields.io/badge/Matrix-%23rust--windowing%3Amatrix.org-blueviolet.svg)](https://matrix.to/#/#rust-windowing:matrix.org) room.
 
 The maintainers have a meeting every friday at UTC 15. The meeting notes can be found [here](https://hackmd.io/@winit-meetings).
 
@@ -35,7 +35,7 @@ another library.
 
 ## MSRV Policy
 
-This crate's Minimum Supported Rust Version (MSRV) is **1.70**. Changes to
+This crate's Minimum Supported Rust Version (MSRV) is **1.73**. Changes to
 the MSRV will be accompanied by a minor version bump.
 
 As a **tentative** policy, the upper bound of the MSRV is given by the following
@@ -50,12 +50,15 @@ Where `sid` is the current version of `rustc` provided by [Debian Sid], and
 
 [Debian Sid]: https://packages.debian.org/sid/rustc
 
-The exception is for the Android platform, where a higher Rust version
+An exception is made for the Android platform, where a higher Rust version
 must be used for certain Android features. In this case, the MSRV will be
 capped at the latest stable version of Rust minus three. This inconsistency is
 not reflected in Cargo metadata, as it is not powerful enough to expose this
 restriction.
 
+Redox OS is also not covered by this MSRV policy, as it requires a Rust nightly
+toolchain to compile.
+
 All crates in the [`rust-windowing`] organizations have the
 same MSRV policy.
 

build.rs

@@ -1,19 +1,18 @@
 use cfg_aliases::cfg_aliases;
 
 fn main() {
-    // The script doesn't depend on our code
+    // The script doesn't depend on our code.
     println!("cargo:rerun-if-changed=build.rs");
 
-    // Setup cfg aliases
+    // Setup cfg aliases.
     cfg_aliases! {
         // Systems.
         android_platform: { target_os = "android" },
         web_platform: { all(target_family = "wasm", target_os = "unknown") },
         macos_platform: { target_os = "macos" },
-        ios_platform: { target_os = "ios" },
+        ios_platform: { all(target_vendor = "apple", not(target_os = "macos")) },
         windows_platform: { target_os = "windows" },
-        apple: { any(target_os = "ios", target_os = "macos") },
-        free_unix: { all(unix, not(apple), not(android_platform), not(target_os = "emscripten")) },
+        free_unix: { all(unix, not(target_vendor = "apple"), not(android_platform), not(target_os = "emscripten")) },
         redox: { target_os = "redox" },
 
         // Native displays.
@@ -21,4 +20,7 @@ fn main() {
         wayland_platform: { all(feature = "wayland", free_unix, not(redox)) },
         orbital_platform: { redox },
     }
+
+    // Winit defined cfgs.
+    println!("cargo:rustc-check-cfg=cfg(unreleased_changelogs)");
 }

clippy.toml

@@ -1,15 +1,16 @@
 disallowed-methods = [
-    { path = "web_sys::window", reason = "is not available in every context" },
-    { path = "web_sys::HtmlCanvasElement::width", reason = "Winit shouldn't touch the internal canvas size" },
-    { path = "web_sys::HtmlCanvasElement::height", reason = "Winit shouldn't touch the internal canvas size" },
-    { path = "web_sys::HtmlCanvasElement::set_width", reason = "Winit shouldn't touch the internal canvas size" },
-    { path = "web_sys::HtmlCanvasElement::set_height", reason = "Winit shouldn't touch the internal canvas size" },
-    { path = "web_sys::Window::document", reason = "cache this to reduce calls to JS" },
-    { path = "web_sys::Window::get_computed_style", reason = "cache this to reduce calls to JS" },
-    { path = "web_sys::HtmlElement::style", reason = "cache this to reduce calls to JS" },
-    { path = "web_sys::Element::request_fullscreen", reason = "Doesn't account for compatibility with Safari" },
-    { path = "web_sys::Document::exit_fullscreen", reason = "Doesn't account for compatibility with Safari" },
-    { path = "web_sys::Document::fullscreen_element", reason = "Doesn't account for compatibility with Safari" },
     { path = "objc2_app_kit::NSView::visibleRect", reason = "We expose a render target to the user, and visibility is not really relevant to that (and can break if you don't use the rectangle position as well). Use `frame` instead." },
     { path = "objc2_app_kit::NSWindow::setFrameTopLeftPoint", reason = "Not sufficient when working with Winit's coordinate system, use `flip_window_screen_coordinates` instead" },
+    { path = "web_sys::Document::exit_fullscreen", reason = "Doesn't account for compatibility with Safari" },
+    { path = "web_sys::Document::fullscreen_element", reason = "Doesn't account for compatibility with Safari" },
+    { path = "web_sys::Element::request_fullscreen", reason = "Doesn't account for compatibility with Safari" },
+    { path = "web_sys::HtmlCanvasElement::height", reason = "Winit shouldn't touch the internal canvas size" },
+    { path = "web_sys::HtmlCanvasElement::set_height", reason = "Winit shouldn't touch the internal canvas size" },
+    { path = "web_sys::HtmlCanvasElement::set_width", reason = "Winit shouldn't touch the internal canvas size" },
+    { path = "web_sys::HtmlCanvasElement::width", reason = "Winit shouldn't touch the internal canvas size" },
+    { path = "web_sys::HtmlElement::style", reason = "cache this to reduce calls to JS" },
+    { path = "web_sys::Window::document", reason = "cache this to reduce calls to JS" },
+    { path = "web_sys::Window::get_computed_style", reason = "cache this to reduce calls to JS" },
+    { path = "web_sys::Window::navigator", reason = "cache this to reduce calls to JS" },
+    { path = "web_sys::window", reason = "is not available in every context" },
 ]

deny.toml

@@ -1,15 +1,20 @@
-# https://embarkstudios.github.io/cargo-deny/
+# https://embarkstudios.github.io/cargo-deny
 # cargo install cargo-deny
-# cargo update && cargo deny --all-features --log-level error --target aarch64-apple-ios check
+# cargo update && cargo deny --target aarch64-apple-ios check
 # Note: running just `cargo deny check` without a `--target` will result in
 # false positives due to https://github.com/EmbarkStudios/cargo-deny/issues/324
+[graph]
+all-features = true
+exclude-dev = true
 targets = [
     { triple = "aarch64-apple-ios" },
     { triple = "aarch64-linux-android" },
     { triple = "i686-pc-windows-gnu" },
     { triple = "i686-pc-windows-msvc" },
     { triple = "i686-unknown-linux-gnu" },
-    { triple = "wasm32-unknown-unknown" },
+    { triple = "wasm32-unknown-unknown", features = [
+        "atomics",
+    ] },
     { triple = "x86_64-apple-darwin" },
     { triple = "x86_64-apple-ios" },
     { triple = "x86_64-pc-windows-gnu" },
@@ -18,46 +23,62 @@ targets = [
     { triple = "x86_64-unknown-redox" },
 ]
 
-
-[advisories]
-vulnerability = "deny"
-unmaintained = "warn"
-yanked = "deny"
-ignore = []
-
+[licenses]
+allow = [
+    "Apache-2.0",       # https://tldrlegal.com/license/apache-license-2.0-(apache-2.0)
+    "BSD-2-Clause",     # https://tldrlegal.com/license/bsd-2-clause-license-(freebsd)
+    "BSD-3-Clause",     # https://tldrlegal.com/license/bsd-3-clause-license-(revised)
+    "ISC",              # https://tldrlegal.com/license/-isc-license
+    "MIT",              # https://tldrlegal.com/license/mit-license
+    "Unicode-DFS-2016", # https://spdx.org/licenses/Unicode-DFS-2016.html
+]
+confidence-threshold = 1.0
+private = { ignore = true }
 
 [bans]
 multiple-versions = "deny"
-wildcards = "allow" # at least until https://github.com/EmbarkStudios/cargo-deny/issues/241 is fixed
-deny = []
-skip = [
-    { name = "raw-window-handle" },    # we intentionally have multiple versions of this
-    { name = "bitflags" },             # the ecosystem is in the process of migrating.
-    { name = "libloading" },           # x11rb uses a different version until the next update
-]
-skip-tree = []
+skip = [{ crate = "bitflags@1", reason = "the ecosystem is in the process of migrating" }]
+wildcards = "allow"                                                                        # at least until https://github.com/EmbarkStudios/cargo-deny/issues/241 is fixed
 
+[bans.build]
+include-archives = true
+interpreted = "deny"
 
-[licenses]
-private = { ignore = true }
-unlicensed = "deny"
-allow-osi-fsf-free = "neither"
-confidence-threshold = 0.92 # We want really high confidence when inferring licenses from text
-copyleft = "deny"
+[[bans.build.bypass]]
 allow = [
-    "Apache-2.0 WITH LLVM-exception", # https://spdx.org/licenses/LLVM-exception.html
-    "Apache-2.0",                     # https://tldrlegal.com/license/apache-license-2.0-(apache-2.0)
-    "BSD-2-Clause",                   # https://tldrlegal.com/license/bsd-2-clause-license-(freebsd)
-    "BSD-3-Clause",                   # https://tldrlegal.com/license/bsd-3-clause-license-(revised)
-    "BSL-1.0",                        # https://tldrlegal.com/license/boost-software-license-1.0-explained
-    "CC0-1.0",                        # https://creativecommons.org/publicdomain/zero/1.0/
-    "ISC",                            # https://tldrlegal.com/license/-isc-license
-    "LicenseRef-UFL-1.0",             # https://tldrlegal.com/license/ubuntu-font-license,-1.0 - no official SPDX, see https://github.com/emilk/egui/issues/2321
-    "MIT-0",                          # https://choosealicense.com/licenses/mit-0/
-    "MIT",                            # https://tldrlegal.com/license/mit-license
-    "MPL-2.0",                        # https://www.mozilla.org/en-US/MPL/2.0/FAQ/ - see Q11. Used by webpki-roots on Linux.
-    "OFL-1.1",                        # https://spdx.org/licenses/OFL-1.1.html
-    "OpenSSL",                        # https://www.openssl.org/source/license.html - used on Linux
-    "Unicode-DFS-2016",               # https://spdx.org/licenses/Unicode-DFS-2016.html
-    "Zlib",                           # https://tldrlegal.com/license/zlib-libpng-license-(zlib)
+    { path = "generate-bindings.sh", checksum = "268ec23248218d779e33853cdc60e2985e70214ff004716cd734270de1f6b561" },
 ]
+crate = "android-activity"
+
+[[bans.build.bypass]]
+allow-globs = ["freetype2/*"]
+crate = "freetype-sys"
+
+[[bans.build.bypass]]
+allow = [
+    { path = "releases/friends.sh", checksum = "f896ccdcb8445d29ed6dd0d9a360f94d4f33af2f1cc9965e7bb38b156c45949d" },
+]
+crate = "wasm-bindgen"
+
+[[bans.build.bypass]]
+allow = [
+    { path = "ui-tests/update-all-references.sh", checksum = "8b8dbf31e7ada1314956db7a20ab14b13af3ae246a6295afdc7dc96af8ec3773" },
+    { path = "ui-tests/update-references.sh", checksum = "65375c25981646e08e8589449a06be4505b1a2c9e10d35f650be4b1b495dff22" },
+]
+crate = "wasm-bindgen-macro"
+
+[[bans.build.bypass]]
+allow-globs = ["lib/*.a"]
+crate = "windows_i686_gnu"
+
+[[bans.build.bypass]]
+allow-globs = ["lib/*.lib"]
+crate = "windows_i686_msvc"
+
+[[bans.build.bypass]]
+allow-globs = ["lib/*.a"]
+crate = "windows_x86_64_gnu"
+
+[[bans.build.bypass]]
+allow-globs = ["lib/*.lib"]
+crate = "windows_x86_64_msvc"

dpi/Cargo.toml

@@ -1,25 +1,26 @@
 [package]
-name = "dpi"
-version = "0.1.1"
-description = "Types for handling UI scaling"
-keywords = ["DPI", "HiDPI", "scale-factor"]
 categories = ["gui"]
-rust-version.workspace = true
-repository.workspace = true
-license.workspace = true
+description = "Types for handling UI scaling"
 edition.workspace = true
+keywords = ["DPI", "HiDPI", "scale-factor"]
+license.workspace = true
+name = "dpi"
+repository.workspace = true
+rust-version.workspace = true
+version = "0.1.1"
 
 [features]
-serde = ["dep:serde"]
 mint = ["dep:mint"]
+serde = ["dep:serde"]
 
 [dependencies]
-serde = { workspace = true, optional = true }
 mint = { workspace = true, optional = true }
+serde = { workspace = true, optional = true }
 
 [package.metadata.docs.rs]
-features = ["serde", "mint"]
+features = ["mint", "serde"]
 # These are all tested in CI
+rustdoc-args = ["--cfg", "docsrs"]
 targets = [
     # Windows
     "i686-pc-windows-msvc",
@@ -36,4 +37,3 @@ targets = [
     # Web
     "wasm32-unknown-unknown",
 ]
-rustdoc-args = ["--cfg", "docsrs"]

dpi/src/lib.rs

@@ -761,9 +761,10 @@ impl<P: Pixel> From<LogicalPosition<P>> for Position {
 
 #[cfg(test)]
 mod tests {
-    use super::*;
     use std::collections::HashSet;
 
+    use super::*;
+
     macro_rules! test_pixel_int_impl {
         ($($name:ident => $ty:ty),*) => {$(
             #[test]

examples/child_window.rs

@@ -1,52 +1,47 @@
-#[cfg(all(feature = "rwh_06", any(x11_platform, macos_platform, windows_platform)))]
+#[cfg(any(x11_platform, macos_platform, windows_platform))]
 #[allow(deprecated)]
 fn main() -> Result<(), impl std::error::Error> {
     use std::collections::HashMap;
 
+    use winit::application::ApplicationHandler;
     use winit::dpi::{LogicalPosition, LogicalSize, Position};
-    use winit::event::{ElementState, Event, KeyEvent, WindowEvent};
+    use winit::event::{ElementState, KeyEvent, WindowEvent};
     use winit::event_loop::{ActiveEventLoop, EventLoop};
     use winit::raw_window_handle::HasRawWindowHandle;
-    use winit::window::Window;
+    use winit::window::{Window, WindowId};
 
     #[path = "util/fill.rs"]
     mod fill;
 
-    fn spawn_child_window(parent: &Window, event_loop: &ActiveEventLoop) -> Window {
-        let parent = parent.raw_window_handle().unwrap();
-        let mut window_attributes = Window::default_attributes()
-            .with_title("child window")
-            .with_inner_size(LogicalSize::new(200.0f32, 200.0f32))
-            .with_position(Position::Logical(LogicalPosition::new(0.0, 0.0)))
-            .with_visible(true);
-        // `with_parent_window` is unsafe. Parent window must be a valid window.
-        window_attributes = unsafe { window_attributes.with_parent_window(Some(parent)) };
-
-        event_loop.create_window(window_attributes).unwrap()
+    #[derive(Default)]
+    struct Application {
+        parent_window_id: Option<WindowId>,
+        windows: HashMap<WindowId, Window>,
     }
 
-    let mut windows = HashMap::new();
+    impl ApplicationHandler for Application {
+        fn can_create_surfaces(&mut self, event_loop: &dyn ActiveEventLoop) {
+            let attributes = Window::default_attributes()
+                .with_title("parent window")
+                .with_position(Position::Logical(LogicalPosition::new(0.0, 0.0)))
+                .with_inner_size(LogicalSize::new(640.0f32, 480.0f32));
+            let window = event_loop.create_window(attributes).unwrap();
 
-    let event_loop: EventLoop<()> = EventLoop::new().unwrap();
-    let mut parent_window_id = None;
+            println!("Parent window id: {:?})", window.id());
+            self.parent_window_id = Some(window.id());
 
-    event_loop.run(move |event: Event<()>, event_loop| {
-        match event {
-            Event::Resumed => {
-                let attributes = Window::default_attributes()
-                    .with_title("parent window")
-                    .with_position(Position::Logical(LogicalPosition::new(0.0, 0.0)))
-                    .with_inner_size(LogicalSize::new(640.0f32, 480.0f32));
-                let window = event_loop.create_window(attributes).unwrap();
+            self.windows.insert(window.id(), window);
+        }
 
-                parent_window_id = Some(window.id());
-
-                println!("Parent window id: {parent_window_id:?})");
-                windows.insert(window.id(), window);
-            },
-            Event::WindowEvent { window_id, event } => match event {
+        fn window_event(
+            &mut self,
+            event_loop: &dyn ActiveEventLoop,
+            window_id: winit::window::WindowId,
+            event: WindowEvent,
+        ) {
+            match event {
                 WindowEvent::CloseRequested => {
-                    windows.clear();
+                    self.windows.clear();
                     event_loop.exit();
                 },
                 WindowEvent::CursorEntered { device_id: _ } => {
@@ -61,25 +56,40 @@ fn main() -> Result<(), impl std::error::Error> {
                     event: KeyEvent { state: ElementState::Pressed, .. },
                     ..
                 } => {
-                    let parent_window = windows.get(&parent_window_id.unwrap()).unwrap();
+                    let parent_window = self.windows.get(&self.parent_window_id.unwrap()).unwrap();
                     let child_window = spawn_child_window(parent_window, event_loop);
                     let child_id = child_window.id();
                     println!("Child window created with id: {child_id:?}");
-                    windows.insert(child_id, child_window);
+                    self.windows.insert(child_id, child_window);
                 },
                 WindowEvent::RedrawRequested => {
-                    if let Some(window) = windows.get(&window_id) {
+                    if let Some(window) = self.windows.get(&window_id) {
                         fill::fill_window(window);
                     }
                 },
                 _ => (),
-            },
-            _ => (),
+            }
         }
-    })
+    }
+
+    fn spawn_child_window(parent: &Window, event_loop: &dyn ActiveEventLoop) -> Window {
+        let parent = parent.raw_window_handle().unwrap();
+        let mut window_attributes = Window::default_attributes()
+            .with_title("child window")
+            .with_inner_size(LogicalSize::new(200.0f32, 200.0f32))
+            .with_position(Position::Logical(LogicalPosition::new(0.0, 0.0)))
+            .with_visible(true);
+        // `with_parent_window` is unsafe. Parent window must be a valid window.
+        window_attributes = unsafe { window_attributes.with_parent_window(Some(parent)) };
+
+        event_loop.create_window(window_attributes).unwrap()
+    }
+
+    let event_loop = EventLoop::new().unwrap();
+    event_loop.run_app(Application::default())
 }
 
-#[cfg(all(feature = "rwh_06", not(any(x11_platform, macos_platform, windows_platform))))]
+#[cfg(not(any(x11_platform, macos_platform, windows_platform)))]
 fn main() {
     panic!(
         "This example is supported only on x11, macOS, and Windows, with the `rwh_06` feature \

examples/control_flow.rs

@@ -7,7 +7,6 @@ use std::time;
 use ::tracing::{info, warn};
 #[cfg(web_platform)]
 use web_time as time;
-
 use winit::application::ApplicationHandler;
 use winit::event::{ElementState, KeyEvent, StartCause, WindowEvent};
 use winit::event_loop::{ActiveEventLoop, ControlFlow, EventLoop};
@@ -44,8 +43,7 @@ fn main() -> Result<(), impl std::error::Error> {
 
     let event_loop = EventLoop::new().unwrap();
 
-    let mut app = ControlFlowDemo::default();
-    event_loop.run_app(&mut app)
+    event_loop.run_app(ControlFlowDemo::default())
 }
 
 #[derive(Default)]
@@ -58,7 +56,7 @@ struct ControlFlowDemo {
 }
 
 impl ApplicationHandler for ControlFlowDemo {
-    fn new_events(&mut self, _event_loop: &ActiveEventLoop, cause: StartCause) {
+    fn new_events(&mut self, _event_loop: &dyn ActiveEventLoop, cause: StartCause) {
         info!("new_events: {cause:?}");
 
         self.wait_cancelled = match cause {
@@ -67,7 +65,7 @@ impl ApplicationHandler for ControlFlowDemo {
         }
     }
 
-    fn resumed(&mut self, event_loop: &ActiveEventLoop) {
+    fn can_create_surfaces(&mut self, event_loop: &dyn ActiveEventLoop) {
         let window_attributes = Window::default_attributes().with_title(
             "Press 1, 2, 3 to change control flow mode. Press R to toggle redraw requests.",
         );
@@ -76,7 +74,7 @@ impl ApplicationHandler for ControlFlowDemo {
 
     fn window_event(
         &mut self,
-        _event_loop: &ActiveEventLoop,
+        _event_loop: &dyn ActiveEventLoop,
         _window_id: WindowId,
         event: WindowEvent,
     ) {
@@ -122,7 +120,7 @@ impl ApplicationHandler for ControlFlowDemo {
         }
     }
 
-    fn about_to_wait(&mut self, event_loop: &ActiveEventLoop) {
+    fn about_to_wait(&mut self, event_loop: &dyn ActiveEventLoop) {
         if self.request_redraw && !self.wait_cancelled && !self.close_requested {
             self.window.as_ref().unwrap().request_redraw();
         }

examples/pump_events.rs

@@ -22,14 +22,14 @@ fn main() -> std::process::ExitCode {
     }
 
     impl ApplicationHandler for PumpDemo {
-        fn resumed(&mut self, event_loop: &ActiveEventLoop) {
+        fn can_create_surfaces(&mut self, event_loop: &dyn ActiveEventLoop) {
             let window_attributes = Window::default_attributes().with_title("A fantastic window!");
             self.window = Some(event_loop.create_window(window_attributes).unwrap());
         }
 
         fn window_event(
             &mut self,
-            event_loop: &ActiveEventLoop,
+            event_loop: &dyn ActiveEventLoop,
             _window_id: WindowId,
             event: WindowEvent,
         ) {

examples/run_on_demand.rs

@@ -22,13 +22,13 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
     }
 
     impl ApplicationHandler for App {
-        fn about_to_wait(&mut self, _event_loop: &ActiveEventLoop) {
+        fn about_to_wait(&mut self, _event_loop: &dyn ActiveEventLoop) {
             if let Some(window) = self.window.as_ref() {
                 window.request_redraw();
             }
         }
 
-        fn resumed(&mut self, event_loop: &ActiveEventLoop) {
+        fn can_create_surfaces(&mut self, event_loop: &dyn ActiveEventLoop) {
             let window_attributes = Window::default_attributes()
                 .with_title("Fantastic window number one!")
                 .with_inner_size(winit::dpi::LogicalSize::new(128.0, 128.0));
@@ -39,7 +39,7 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
 
         fn window_event(
             &mut self,
-            event_loop: &ActiveEventLoop,
+            event_loop: &dyn ActiveEventLoop,
             window_id: WindowId,
             event: WindowEvent,
         ) {

examples/util/fill.rs

@@ -11,7 +11,7 @@
 pub use platform::cleanup_window;
 pub use platform::fill_window;
 
-#[cfg(all(feature = "rwh_05", not(any(target_os = "android", target_os = "ios"))))]
+#[cfg(all(feature = "rwh_06", not(any(target_os = "android", target_os = "ios"))))]
 mod platform {
     use std::cell::RefCell;
     use std::collections::HashMap;
@@ -104,7 +104,7 @@ mod platform {
     }
 }
 
-#[cfg(not(all(feature = "rwh_05", not(any(target_os = "android", target_os = "ios")))))]
+#[cfg(not(all(feature = "rwh_06", not(any(target_os = "android", target_os = "ios")))))]
 mod platform {
     pub fn fill_window(_window: &winit::window::Window) {
         // No-op on mobile platforms.

examples/window.rs

@@ -5,6 +5,7 @@ use std::error::Error;
 use std::fmt::Debug;
 #[cfg(not(any(android_platform, ios_platform)))]
 use std::num::NonZeroU32;
+use std::sync::mpsc::{self, Receiver, Sender};
 use std::sync::Arc;
 use std::{fmt, mem};
 
@@ -14,23 +15,25 @@ use cursor_icon::CursorIcon;
 use rwh_06::{DisplayHandle, HasDisplayHandle};
 #[cfg(not(any(android_platform, ios_platform)))]
 use softbuffer::{Context, Surface};
-
 use winit::application::ApplicationHandler;
 use winit::dpi::{LogicalSize, PhysicalPosition, PhysicalSize};
+use winit::error::ExternalError;
 use winit::event::{DeviceEvent, DeviceId, Ime, MouseButton, MouseScrollDelta, WindowEvent};
 use winit::event_loop::{ActiveEventLoop, EventLoop};
 use winit::keyboard::{Key, ModifiersState};
-use winit::window::{
-    Cursor, CursorGrabMode, CustomCursor, CustomCursorSource, Fullscreen, Icon, ResizeDirection,
-    Theme, Window, WindowId,
-};
-
 #[cfg(macos_platform)]
 use winit::platform::macos::{OptionAsAlt, WindowAttributesExtMacOS, WindowExtMacOS};
 #[cfg(any(x11_platform, wayland_platform))]
 use winit::platform::startup_notify::{
     self, EventLoopExtStartupNotify, WindowAttributesExtStartupNotify, WindowExtStartupNotify,
 };
+use winit::platform::wayland::{EventLoopExtWayland, WaylandApplicationHandler};
+#[cfg(web_platform)]
+use winit::platform::web::{ActiveEventLoopExtWeb, CustomCursorExtWeb, WindowAttributesExtWeb};
+use winit::window::{
+    Cursor, CursorGrabMode, CustomCursor, CustomCursorSource, Fullscreen, Icon, ResizeDirection,
+    Theme, Window, WindowId,
+};
 
 #[path = "util/tracing.rs"]
 mod tracing;
@@ -44,36 +47,38 @@ fn main() -> Result<(), Box<dyn Error>> {
 
     tracing::init();
 
-    let event_loop = EventLoop::<UserEvent>::with_user_event().build()?;
-    let _event_loop_proxy = event_loop.create_proxy();
+    let mut event_loop = EventLoop::new()?;
+    let (sender, receiver) = mpsc::channel();
 
     // Wire the user event from another thread.
     #[cfg(not(web_platform))]
-    std::thread::spawn(move || {
-        // Wake up the `event_loop` once every second and dispatch a custom event
-        // from a different thread.
-        info!("Starting to send user event every second");
-        loop {
-            let _ = _event_loop_proxy.send_event(UserEvent::WakeUp);
-            std::thread::sleep(std::time::Duration::from_secs(1));
-        }
-    });
+    {
+        let event_loop_proxy = event_loop.create_proxy();
+        let sender = sender.clone();
+        std::thread::spawn(move || {
+            // Wake up the `event_loop` once every second and dispatch a custom event
+            // from a different thread.
+            info!("Starting to send user event every second");
+            loop {
+                let _ = sender.send(Action::Message);
+                event_loop_proxy.wake_up();
+                std::thread::sleep(std::time::Duration::from_secs(1));
+            }
+        });
+    }
 
-    let mut state = Application::new(&event_loop);
-
-    event_loop.run_app(&mut state).map_err(Into::into)
-}
-
-#[allow(dead_code)]
-#[derive(Debug, Clone, Copy)]
-enum UserEvent {
-    WakeUp,
+    let app = Application::new(&event_loop, receiver, sender);
+    event_loop.register_wayland_callback::<Application>();
+    Ok(event_loop.run_app(app)?)
 }
 
 /// Application state and event handling.
 struct Application {
+    /// Trigger actions through proxy wake up.
+    receiver: Receiver<Action>,
+    sender: Sender<Action>,
     /// Custom cursors assets.
-    custom_cursors: Vec<CustomCursor>,
+    custom_cursors: Result<Vec<CustomCursor>, ExternalError>,
     /// Application icon.
     icon: Icon,
     windows: HashMap<WindowId, WindowState>,
@@ -85,7 +90,7 @@ struct Application {
 }
 
 impl Application {
-    fn new<T>(event_loop: &EventLoop<T>) -> Self {
+    fn new(event_loop: &EventLoop, receiver: Receiver<Action>, sender: Sender<Action>) -> Self {
         // SAFETY: we drop the context right before the event loop is stopped, thus making it safe.
         #[cfg(not(any(android_platform, ios_platform)))]
         let context = Some(
@@ -105,13 +110,17 @@ impl Application {
         let icon = load_icon(include_bytes!("data/icon.png"));
 
         info!("Loading cursor assets");
-        let custom_cursors = vec![
+        let custom_cursors = [
             event_loop.create_custom_cursor(decode_cursor(include_bytes!("data/cross.png"))),
             event_loop.create_custom_cursor(decode_cursor(include_bytes!("data/cross2.png"))),
             event_loop.create_custom_cursor(decode_cursor(include_bytes!("data/gradient.png"))),
-        ];
+        ]
+        .into_iter()
+        .collect();
 
         Self {
+            receiver,
+            sender,
             #[cfg(not(any(android_platform, ios_platform)))]
             context,
             custom_cursors,
@@ -122,7 +131,7 @@ impl Application {
 
     fn create_window(
         &mut self,
-        event_loop: &ActiveEventLoop,
+        event_loop: &dyn ActiveEventLoop,
         _tab_id: Option<String>,
     ) -> Result<WindowId, Box<dyn Error>> {
         // TODO read-out activation token.
@@ -147,7 +156,6 @@ impl Application {
 
         #[cfg(web_platform)]
         {
-            use winit::platform::web::WindowAttributesExtWebSys;
             window_attributes = window_attributes.with_append(true);
         }
 
@@ -169,7 +177,23 @@ impl Application {
         Ok(window_id)
     }
 
-    fn handle_action(&mut self, event_loop: &ActiveEventLoop, window_id: WindowId, action: Action) {
+    fn handle_action_from_proxy(&mut self, _event_loop: &dyn ActiveEventLoop, action: Action) {
+        match action {
+            #[cfg(web_platform)]
+            Action::DumpMonitors => self.dump_monitors(_event_loop),
+            Action::Message => {
+                info!("User wake up");
+            },
+            _ => unreachable!("Tried to execute invalid action without `WindowId`"),
+        }
+    }
+
+    fn handle_action_with_window(
+        &mut self,
+        event_loop: &dyn ActiveEventLoop,
+        window_id: WindowId,
+        action: Action,
+    ) {
         // let cursor_position = self.cursor_position;
         let window = self.windows.get_mut(&window_id).unwrap();
         info!("Executing action: {action:?}");
@@ -198,12 +222,27 @@ impl Application {
             Action::ToggleImeInput => window.toggle_ime(),
             Action::Minimize => window.minimize(),
             Action::NextCursor => window.next_cursor(),
-            Action::NextCustomCursor => window.next_custom_cursor(&self.custom_cursors),
+            Action::NextCustomCursor => {
+                if let Err(err) = self.custom_cursors.as_ref().map(|c| window.next_custom_cursor(c))
+                {
+                    error!("Error creating custom cursor: {err}");
+                }
+            },
             #[cfg(web_platform)]
-            Action::UrlCustomCursor => window.url_custom_cursor(event_loop),
+            Action::UrlCustomCursor => {
+                if let Err(err) = window.url_custom_cursor(event_loop) {
+                    error!("Error creating custom cursor from URL: {err}");
+                }
+            },
             #[cfg(web_platform)]
             Action::AnimationCustomCursor => {
-                window.animation_custom_cursor(event_loop, &self.custom_cursors)
+                if let Err(err) = self
+                    .custom_cursors
+                    .as_ref()
+                    .map(|c| window.animation_custom_cursor(event_loop, c))
+                {
+                    error!("Error creating animated custom cursor: {err}");
+                }
             },
             Action::CycleCursorGrab => window.cycle_cursor_grab(),
             Action::DragWindow => window.drag_window(),
@@ -212,6 +251,12 @@ impl Application {
             Action::PrintHelp => self.print_help(),
             #[cfg(macos_platform)]
             Action::CycleOptionAsAlt => window.cycle_option_as_alt(),
+            Action::SetTheme(theme) => {
+                window.window.set_theme(theme);
+                // Get the resulting current theme to draw with
+                let actual_theme = theme.or_else(|| window.window.theme()).unwrap_or(Theme::Dark);
+                window.set_draw_theme(actual_theme);
+            },
             #[cfg(macos_platform)]
             Action::CreateNewTab => {
                 let tab_id = window.window.tabbing_identifier();
@@ -220,10 +265,30 @@ impl Application {
                 }
             },
             Action::RequestResize => window.swap_dimensions(),
+            #[cfg(web_platform)]
+            Action::DumpMonitors => {
+                let future = event_loop.request_detailed_monitor_permission();
+                let proxy = event_loop.create_proxy();
+                let sender = self.sender.clone();
+                wasm_bindgen_futures::spawn_local(async move {
+                    if let Err(error) = future.await {
+                        error!("{error}")
+                    }
+
+                    let _ = sender.send(Action::DumpMonitors);
+                    proxy.wake_up();
+                });
+            },
+            #[cfg(not(web_platform))]
+            Action::DumpMonitors => self.dump_monitors(event_loop),
+            Action::Message => {
+                self.sender.send(Action::Message).unwrap();
+                event_loop.create_proxy().wake_up();
+            },
         }
     }
 
-    fn dump_monitors(&self, event_loop: &ActiveEventLoop) {
+    fn dump_monitors(&self, event_loop: &dyn ActiveEventLoop) {
         info!("Monitors information");
         let primary_monitor = event_loop.primary_monitor();
         for monitor in event_loop.available_monitors() {
@@ -239,27 +304,32 @@ impl Application {
                 info!("{intro}: [no name]");
             }
 
-            let PhysicalSize { width, height } = monitor.size();
-            info!(
-                "  Current mode: {width}x{height}{}",
-                if let Some(m_hz) = monitor.refresh_rate_millihertz() {
-                    format!(" @ {}.{} Hz", m_hz / 1000, m_hz % 1000)
-                } else {
-                    String::new()
-                }
-            );
+            if let Some(current_mode) = monitor.current_video_mode() {
+                let PhysicalSize { width, height } = current_mode.size();
+                let bits =
+                    current_mode.bit_depth().map(|bits| format!("x{bits}")).unwrap_or_default();
+                let m_hz = current_mode
+                    .refresh_rate_millihertz()
+                    .map(|m_hz| format!(" @ {}.{} Hz", m_hz.get() / 1000, m_hz.get() % 1000))
+                    .unwrap_or_default();
+                info!("  {width}x{height}{bits}{m_hz}");
+            }
 
-            let PhysicalPosition { x, y } = monitor.position();
-            info!("  Position: {x},{y}");
+            if let Some(PhysicalPosition { x, y }) = monitor.position() {
+                info!("  Position: {x},{y}");
+            }
 
             info!("  Scale factor: {}", monitor.scale_factor());
 
             info!("  Available modes (width x height x bit-depth):");
             for mode in monitor.video_modes() {
                 let PhysicalSize { width, height } = mode.size();
-                let bits = mode.bit_depth();
-                let m_hz = mode.refresh_rate_millihertz();
-                info!("    {width}x{height}x{bits} @ {}.{} Hz", m_hz / 1000, m_hz % 1000);
+                let bits = mode.bit_depth().map(|bits| format!("x{bits}")).unwrap_or_default();
+                let m_hz = mode
+                    .refresh_rate_millihertz()
+                    .map(|m_hz| format!(" @ {}.{} Hz", m_hz.get() / 1000, m_hz.get() % 1000))
+                    .unwrap_or_default();
+                info!("    {width}x{height}{bits}{m_hz}");
             }
         }
     }
@@ -302,14 +372,21 @@ impl Application {
     }
 }
 
-impl ApplicationHandler<UserEvent> for Application {
-    fn user_event(&mut self, _event_loop: &ActiveEventLoop, event: UserEvent) {
-        info!("User event: {event:?}");
+impl ApplicationHandler for Application {
+    fn as_any(&mut self) -> Option<&mut dyn std::any::Any> {
+        println!("Called");
+        Some(self)
+    }
+
+    fn proxy_wake_up(&mut self, event_loop: &dyn ActiveEventLoop) {
+        while let Ok(action) = self.receiver.try_recv() {
+            self.handle_action_from_proxy(event_loop, action)
+        }
     }
 
     fn window_event(
         &mut self,
-        event_loop: &ActiveEventLoop,
+        event_loop: &dyn ActiveEventLoop,
         window_id: WindowId,
         event: WindowEvent,
     ) {
@@ -334,7 +411,7 @@ impl ApplicationHandler<UserEvent> for Application {
             },
             WindowEvent::ThemeChanged(theme) => {
                 info!("Theme changed to {theme:?}");
-                window.set_theme(theme);
+                window.set_draw_theme(theme);
             },
             WindowEvent::RedrawRequested => {
                 if let Err(err) = window.draw() {
@@ -372,7 +449,7 @@ impl ApplicationHandler<UserEvent> for Application {
                     };
 
                     if let Some(action) = action {
-                        self.handle_action(event_loop, window_id, action);
+                        self.handle_action_with_window(event_loop, window_id, action);
                     }
                 }
             },
@@ -381,7 +458,7 @@ impl ApplicationHandler<UserEvent> for Application {
                 if let Some(action) =
                     state.is_pressed().then(|| Self::process_mouse_binding(button, &mods)).flatten()
                 {
-                    self.handle_action(event_loop, window_id, action);
+                    self.handle_action_with_window(event_loop, window_id, action);
                 }
             },
             WindowEvent::CursorLeft { .. } => {
@@ -441,7 +518,6 @@ impl ApplicationHandler<UserEvent> for Application {
             | WindowEvent::HoveredFileCancelled
             | WindowEvent::KeyboardInput { .. }
             | WindowEvent::CursorEntered { .. }
-            | WindowEvent::AxisMotion { .. }
             | WindowEvent::DroppedFile(_)
             | WindowEvent::HoveredFile(_)
             | WindowEvent::Destroyed
@@ -452,15 +528,15 @@ impl ApplicationHandler<UserEvent> for Application {
 
     fn device_event(
         &mut self,
-        _event_loop: &ActiveEventLoop,
+        _event_loop: &dyn ActiveEventLoop,
         device_id: DeviceId,
         event: DeviceEvent,
     ) {
         info!("Device {device_id:?} event: {event:?}");
     }
 
-    fn resumed(&mut self, event_loop: &ActiveEventLoop) {
-        info!("Resumed the event loop");
+    fn can_create_surfaces(&mut self, event_loop: &dyn ActiveEventLoop) {
+        info!("Ready to create surfaces");
         self.dump_monitors(event_loop);
 
         // Create initial window.
@@ -469,7 +545,7 @@ impl ApplicationHandler<UserEvent> for Application {
         self.print_help();
     }
 
-    fn about_to_wait(&mut self, event_loop: &ActiveEventLoop) {
+    fn about_to_wait(&mut self, event_loop: &dyn ActiveEventLoop) {
         if self.windows.is_empty() {
             info!("No windows left, exiting...");
             event_loop.exit();
@@ -477,12 +553,18 @@ impl ApplicationHandler<UserEvent> for Application {
     }
 
     #[cfg(not(any(android_platform, ios_platform)))]
-    fn exiting(&mut self, _event_loop: &ActiveEventLoop) {
+    fn exiting(&mut self, _event_loop: &dyn ActiveEventLoop) {
         // We must drop the context here.
         self.context = None;
     }
 }
 
+impl WaylandApplicationHandler for Application {
+    fn wayland_callback(&mut self) {
+        println!("Wayland callback!");
+    }
+}
+
 /// State of the window.
 struct WindowState {
     /// IME input.
@@ -542,7 +624,7 @@ impl WindowState {
         let mut state = Self {
             #[cfg(macos_platform)]
             option_as_alt: window.option_as_alt(),
-            custom_idx: app.custom_cursors.len() - 1,
+            custom_idx: app.custom_cursors.as_ref().map(Vec::len).unwrap_or(1) - 1,
             cursor_grab: CursorGrabMode::None,
             named_idx,
             #[cfg(not(any(android_platform, ios_platform)))]
@@ -691,31 +773,37 @@ impl WindowState {
 
     /// Custom cursor from an URL.
     #[cfg(web_platform)]
-    fn url_custom_cursor(&mut self, event_loop: &ActiveEventLoop) {
-        let cursor = event_loop.create_custom_cursor(url_custom_cursor());
+    fn url_custom_cursor(
+        &mut self,
+        event_loop: &dyn ActiveEventLoop,
+    ) -> Result<(), Box<dyn Error>> {
+        let cursor = event_loop.create_custom_cursor(url_custom_cursor())?;
 
         self.window.set_cursor(cursor);
+
+        Ok(())
     }
 
     /// Custom cursor from a URL.
     #[cfg(web_platform)]
     fn animation_custom_cursor(
         &mut self,
-        event_loop: &ActiveEventLoop,
+        event_loop: &dyn ActiveEventLoop,
         custom_cursors: &[CustomCursor],
-    ) {
+    ) -> Result<(), Box<dyn Error>> {
         use std::time::Duration;
-        use winit::platform::web::CustomCursorExtWebSys;
 
         let cursors = vec![
             custom_cursors[0].clone(),
             custom_cursors[1].clone(),
-            event_loop.create_custom_cursor(url_custom_cursor()),
+            event_loop.create_custom_cursor(url_custom_cursor())?,
         ];
         let cursor = CustomCursor::from_animation(Duration::from_secs(3), cursors).unwrap();
-        let cursor = event_loop.create_custom_cursor(cursor);
+        let cursor = event_loop.create_custom_cursor(cursor)?;
 
         self.window.set_cursor(cursor);
+
+        Ok(())
     }
 
     /// Resize the window to the new size.
@@ -733,8 +821,8 @@ impl WindowState {
         self.window.request_redraw();
     }
 
-    /// Change the theme.
-    fn set_theme(&mut self, theme: Theme) {
+    /// Change the theme that things are drawn in.
+    fn set_draw_theme(&mut self, theme: Theme) {
         self.theme = theme;
         self.window.request_redraw();
     }
@@ -884,9 +972,12 @@ enum Action {
     ShowWindowMenu,
     #[cfg(macos_platform)]
     CycleOptionAsAlt,
+    SetTheme(Option<Theme>),
     #[cfg(macos_platform)]
     CreateNewTab,
     RequestResize,
+    DumpMonitors,
+    Message,
 }
 
 impl Action {
@@ -915,9 +1006,20 @@ impl Action {
             Action::ShowWindowMenu => "Show window menu",
             #[cfg(macos_platform)]
             Action::CycleOptionAsAlt => "Cycle option as alt mode",
+            Action::SetTheme(None) => "Change to the system theme",
+            Action::SetTheme(Some(Theme::Light)) => "Change to a light theme",
+            Action::SetTheme(Some(Theme::Dark)) => "Change to a dark theme",
             #[cfg(macos_platform)]
             Action::CreateNewTab => "Create new tab",
             Action::RequestResize => "Request a resize",
+            #[cfg(not(web_platform))]
+            Action::DumpMonitors => "Dump monitor information",
+            #[cfg(web_platform)]
+            Action::DumpMonitors => {
+                "Request permission to query detailed monitor information and dump monitor \
+                 information"
+            },
+            Action::Message => "Prints a message through a user wake up",
         }
     }
 }
@@ -940,8 +1042,6 @@ fn decode_cursor(bytes: &[u8]) -> CustomCursorSource {
 fn url_custom_cursor() -> CustomCursorSource {
     use std::sync::atomic::{AtomicU64, Ordering};
 
-    use winit::platform::web::CustomCursorExtWebSys;
-
     static URL_COUNTER: AtomicU64 = AtomicU64::new(0);
 
     CustomCursor::from_url(
@@ -1039,6 +1139,7 @@ const KEY_BINDINGS: &[Binding<&'static str>] = &[
     Binding::new("R", ModifiersState::CONTROL, Action::ToggleResizable),
     Binding::new("R", ModifiersState::ALT, Action::RequestResize),
     // M.
+    Binding::new("M", ModifiersState::CONTROL.union(ModifiersState::ALT), Action::DumpMonitors),
     Binding::new("M", ModifiersState::CONTROL, Action::ToggleMaximize),
     Binding::new("M", ModifiersState::ALT, Action::Minimize),
     // N.
@@ -1059,10 +1160,15 @@ const KEY_BINDINGS: &[Binding<&'static str>] = &[
         Action::AnimationCustomCursor,
     ),
     Binding::new("Z", ModifiersState::CONTROL, Action::ToggleCursorVisibility),
+    // K.
+    Binding::new("K", ModifiersState::empty(), Action::SetTheme(None)),
+    Binding::new("K", ModifiersState::SUPER, Action::SetTheme(Some(Theme::Light))),
+    Binding::new("K", ModifiersState::CONTROL, Action::SetTheme(Some(Theme::Dark))),
     #[cfg(macos_platform)]
     Binding::new("T", ModifiersState::SUPER, Action::CreateNewTab),
     #[cfg(macos_platform)]
     Binding::new("O", ModifiersState::CONTROL, Action::CycleOptionAsAlt),
+    Binding::new("S", ModifiersState::CONTROL, Action::Message),
 ];
 
 const MOUSE_BINDINGS: &[Binding<MouseButton>] = &[

examples/x11_embed.rs

@@ -18,7 +18,7 @@ fn main() -> Result<(), Box<dyn Error>> {
     }
 
     impl ApplicationHandler for XEmbedDemo {
-        fn resumed(&mut self, event_loop: &ActiveEventLoop) {
+        fn can_create_surfaces(&mut self, event_loop: &dyn ActiveEventLoop) {
             let window_attributes = Window::default_attributes()
                 .with_title("An embedded window!")
                 .with_inner_size(winit::dpi::LogicalSize::new(128.0, 128.0))
@@ -29,7 +29,7 @@ fn main() -> Result<(), Box<dyn Error>> {
 
         fn window_event(
             &mut self,
-            event_loop: &ActiveEventLoop,
+            event_loop: &dyn ActiveEventLoop,
             _window_id: WindowId,
             event: WindowEvent,
         ) {
@@ -44,7 +44,7 @@ fn main() -> Result<(), Box<dyn Error>> {
             }
         }
 
-        fn about_to_wait(&mut self, _event_loop: &ActiveEventLoop) {
+        fn about_to_wait(&mut self, _event_loop: &dyn ActiveEventLoop) {
             self.window.as_ref().unwrap().request_redraw();
         }
     }
@@ -58,8 +58,7 @@ fn main() -> Result<(), Box<dyn Error>> {
     tracing_subscriber::fmt::init();
     let event_loop = EventLoop::new()?;
 
-    let mut app = XEmbedDemo { parent_window_id, window: None };
-    event_loop.run_app(&mut app).map_err(Into::into)
+    Ok(event_loop.run_app(XEmbedDemo { parent_window_id, window: None })?)
 }
 
 #[cfg(not(x11_platform))]

rustfmt.toml

@@ -1,19 +1,20 @@
-format_code_in_doc_comments = true
-match_block_trailing_comma = true
+comment_width = 100
 condense_wildcard_suffixes = true
-use_field_init_shorthand = true
+error_on_unformatted = true
+format_code_in_doc_comments = true
+format_macro_bodies = true
+format_macro_matchers = true
+format_strings = true
+group_imports = "StdExternalCrate"
+hex_literal_case = "Lower"
+imports_granularity = "Module"
+match_block_trailing_comma = true
+newline_style = "Unix"
+normalize_comments = true
 normalize_doc_attributes = true
 overflow_delimited_expr = true
-imports_granularity = "Module"
-use_small_heuristics = "Max"
-format_macro_matchers = true
-error_on_unformatted = true
-format_macro_bodies = true
-hex_literal_case = "Lower"
-normalize_comments = true
 # Some macros break with this.
 reorder_impl_items = false
-newline_style = "Unix"
-format_strings = true
+use_field_init_shorthand = true
+use_small_heuristics = "Max"
 wrap_comments = true
-comment_width = 100

src/application.rs

@@ -1,98 +1,195 @@
 //! End user application handling.
 
+use std::any::Any;
+
 use crate::event::{DeviceEvent, DeviceId, StartCause, WindowEvent};
 use crate::event_loop::ActiveEventLoop;
 use crate::window::WindowId;
 
 /// The handler of the application events.
-pub trait ApplicationHandler<T: 'static = ()> {
+pub trait ApplicationHandler {
     /// Emitted when new events arrive from the OS to be processed.
     ///
     /// This is a useful place to put code that should be done before you start processing
     /// events, such as updating frame timing information for benchmarking or checking the
     /// [`StartCause`] to see if a timer set by
     /// [`ControlFlow::WaitUntil`][crate::event_loop::ControlFlow::WaitUntil] has elapsed.
-    fn new_events(&mut self, event_loop: &ActiveEventLoop, cause: StartCause) {
+    fn new_events(&mut self, event_loop: &dyn ActiveEventLoop, cause: StartCause) {
         let _ = (event_loop, cause);
     }
 
     /// Emitted when the application has been resumed.
     ///
-    /// For consistency, all platforms emit a `Resumed` event even if they don't themselves have a
-    /// formal suspend/resume lifecycle. For systems without a formal suspend/resume lifecycle
-    /// the `Resumed` event is always emitted after the
-    /// [`NewEvents(StartCause::Init)`][StartCause::Init] event.
+    /// See [`suspended()`][Self::suspended].
     ///
-    /// # Portability
+    /// ## Platform-specific
     ///
-    /// It's recommended that applications should only initialize their graphics context and create
-    /// a window after they have received their first `Resumed` event. Some systems
-    /// (specifically Android) won't allow applications to create a render surface until they are
-    /// resumed.
+    /// ### iOS
     ///
-    /// Considering that the implementation of [`Suspended`] and `Resumed` events may be internally
-    /// driven by multiple platform-specific events, and that there may be subtle differences across
-    /// platforms with how these internal events are delivered, it's recommended that applications
-    /// be able to gracefully handle redundant (i.e. back-to-back) [`Suspended`] or `Resumed`
-    /// events.
+    /// On iOS, the [`resumed()`] method is called in response to an [`applicationDidBecomeActive`]
+    /// callback which means the application is about to transition from the inactive to active
+    /// state (according to the [iOS application lifecycle]).
     ///
-    /// Also see [`Suspended`] notes.
+    /// [`applicationDidBecomeActive`]: https://developer.apple.com/documentation/uikit/uiapplicationdelegate/1622956-applicationdidbecomeactive
+    /// [iOS application lifecycle]: https://developer.apple.com/documentation/uikit/app_and_environment/managing_your_app_s_life_cycle
     ///
-    /// ## Android
+    /// ### Web
     ///
-    /// On Android, the `Resumed` event is sent when a new [`SurfaceView`] has been created. This is
-    /// expected to closely correlate with the [`onResume`] lifecycle event but there may
-    /// technically be a discrepancy.
+    /// On Web, the [`resumed()`] method is called in response to a [`pageshow`] event if the
+    /// page is being restored from the [`bfcache`] (back/forward cache) - an in-memory cache
+    /// that stores a complete snapshot of a page (including the JavaScript heap) as the user is
+    /// navigating away.
+    ///
+    /// [`pageshow`]: https://developer.mozilla.org/en-US/docs/Web/API/Window/pageshow_event
+    /// [`bfcache`]: https://web.dev/bfcache/
+    ///
+    /// ### Others
+    ///
+    /// **Android / macOS / Orbital / Wayland / Windows / X11:** Unsupported.
+    ///
+    /// [`resumed()`]: Self::resumed
+    fn resumed(&mut self, event_loop: &dyn ActiveEventLoop) {
+        let _ = event_loop;
+    }
+
+    /// Emitted from the point onwards the application should create render surfaces.
+    ///
+    /// See [`destroy_surfaces()`].
+    ///
+    /// ## Portability
+    ///
+    /// It's recommended that applications should only initialize their render surfaces after the
+    /// [`can_create_surfaces()`] method is called. Some systems (specifically Android) won't allow
+    /// applications to create a render surface until that point.
+    ///
+    /// For consistency, all platforms call this method even if they don't themselves have a formal
+    /// surface destroy/create lifecycle. For systems without a surface destroy/create lifecycle the
+    /// [`can_create_surfaces()`] event is always emitted after the [`StartCause::Init`] event.
+    ///
+    /// Applications should be able to gracefully handle back-to-back [`can_create_surfaces()`] and
+    /// [`destroy_surfaces()`] calls.
+    ///
+    /// ## Platform-specific
+    ///
+    /// ### Android
+    ///
+    /// On Android, the [`can_create_surfaces()`] method is called when a new [`SurfaceView`] has
+    /// been created. This is expected to closely correlate with the [`onResume`] lifecycle
+    /// event but there may technically be a discrepancy.
     ///
     /// [`onResume`]: https://developer.android.com/reference/android/app/Activity#onResume()
     ///
-    /// Applications that need to run on Android must wait until they have been `Resumed`
-    /// before they will be able to create a render surface (such as an `EGLSurface`,
-    /// [`VkSurfaceKHR`] or [`wgpu::Surface`]) which depend on having a
-    /// [`SurfaceView`]. Applications must also assume that if they are [`Suspended`], then their
-    /// render surfaces are invalid and should be dropped.
-    ///
-    /// Also see [`Suspended`] notes.
+    /// Applications that need to run on Android must wait until they have been "resumed" before
+    /// they will be able to create a render surface (such as an `EGLSurface`, [`VkSurfaceKHR`]
+    /// or [`wgpu::Surface`]) which depend on having a [`SurfaceView`]. Applications must also
+    /// assume that if they are [suspended], then their render surfaces are invalid and should
+    /// be dropped.
     ///
+    /// [suspended]: Self::destroy_surfaces
     /// [`SurfaceView`]: https://developer.android.com/reference/android/view/SurfaceView
     /// [Activity lifecycle]: https://developer.android.com/guide/components/activities/activity-lifecycle
     /// [`VkSurfaceKHR`]: https://www.khronos.org/registry/vulkan/specs/1.3-extensions/man/html/VkSurfaceKHR.html
     /// [`wgpu::Surface`]: https://docs.rs/wgpu/latest/wgpu/struct.Surface.html
     ///
-    /// ## iOS
-    ///
-    /// On iOS, the `Resumed` event is emitted in response to an [`applicationDidBecomeActive`]
-    /// callback which means the application is "active" (according to the
-    /// [iOS application lifecycle]).
-    ///
-    /// [`applicationDidBecomeActive`]: https://developer.apple.com/documentation/uikit/uiapplicationdelegate/1622956-applicationdidbecomeactive
-    /// [iOS application lifecycle]: https://developer.apple.com/documentation/uikit/app_and_environment/managing_your_app_s_life_cycle
-    ///
-    /// ## Web
-    ///
-    /// On Web, the `Resumed` event is emitted in response to a [`pageshow`] event
-    /// with the property [`persisted`] being true, which means that the page is being
-    /// restored from the [`bfcache`] (back/forward cache) - an in-memory cache that
-    /// stores a complete snapshot of a page (including the JavaScript heap) as the
-    /// user is navigating away.
-    ///
-    /// [`pageshow`]: https://developer.mozilla.org/en-US/docs/Web/API/Window/pageshow_event
-    /// [`persisted`]: https://developer.mozilla.org/en-US/docs/Web/API/PageTransitionEvent/persisted
-    /// [`bfcache`]: https://web.dev/bfcache/
-    /// [`Suspended`]: Self::suspended
-    fn resumed(&mut self, event_loop: &ActiveEventLoop);
+    /// [`can_create_surfaces()`]: Self::can_create_surfaces
+    /// [`destroy_surfaces()`]: Self::destroy_surfaces
+    fn can_create_surfaces(&mut self, event_loop: &dyn ActiveEventLoop);
 
-    /// Emitted when an event is sent from [`EventLoopProxy::send_event`].
+    /// Called after a wake up is requested using [`EventLoopProxy::wake_up()`].
     ///
-    /// [`EventLoopProxy::send_event`]: crate::event_loop::EventLoopProxy::send_event
-    fn user_event(&mut self, event_loop: &ActiveEventLoop, event: T) {
-        let _ = (event_loop, event);
+    /// Multiple calls to the aforementioned method will be merged, and will only wake the event
+    /// loop once; however, due to the nature of multi-threading some wake ups may appear
+    /// spuriously. For these reasons, you should not rely on the number of times that this was
+    /// called.
+    ///
+    /// The order in which this is emitted in relation to other events is not guaranteed. The time
+    /// at which this will be emitted is not guaranteed, only that it will happen "soon". That is,
+    /// there may be several executions of the event loop, including multiple redraws to windows,
+    /// between [`EventLoopProxy::wake_up()`] being called and the event being delivered.
+    ///
+    /// [`EventLoopProxy::wake_up()`]: crate::event_loop::EventLoopProxy::wake_up
+    ///
+    /// # Example
+    ///
+    /// Use a [`std::sync::mpsc`] channel to handle events from a different thread.
+    ///
+    /// ```no_run
+    /// use std::sync::mpsc;
+    /// use std::thread;
+    /// use std::time::Duration;
+    ///
+    /// use winit::application::ApplicationHandler;
+    /// use winit::event_loop::{ActiveEventLoop, EventLoop};
+    ///
+    /// struct MyApp {
+    ///     receiver: mpsc::Receiver<u64>,
+    /// }
+    ///
+    /// impl ApplicationHandler for MyApp {
+    ///     # fn window_event(
+    ///     #     &mut self,
+    ///     #     _event_loop: &dyn ActiveEventLoop,
+    ///     #     _window_id: winit::window::WindowId,
+    ///     #     _event: winit::event::WindowEvent,
+    ///     # ) {
+    ///     # }
+    ///     #
+    ///     # fn can_create_surfaces(&mut self, _event_loop: &dyn ActiveEventLoop) {}
+    ///     #
+    ///     fn proxy_wake_up(&mut self, _event_loop: &dyn ActiveEventLoop) {
+    ///         // Iterate current events, since wake-ups may have been merged.
+    ///         //
+    ///         // Note: We take care not to use `recv` or `iter` here, as those are blocking,
+    ///         // and that would be bad for performance and might lead to a deadlock.
+    ///         for i in self.receiver.try_iter() {
+    ///             println!("received: {i}");
+    ///         }
+    ///     }
+    ///
+    ///     // Rest of `ApplicationHandler`
+    /// }
+    ///
+    /// fn main() -> Result<(), Box<dyn std::error::Error>> {
+    ///     let event_loop = EventLoop::new()?;
+    ///
+    ///     let (sender, receiver) = mpsc::channel();
+    ///
+    ///     let mut app = MyApp { receiver };
+    ///
+    ///     // Send an event in a loop
+    ///     let proxy = event_loop.create_proxy();
+    ///     let background_thread = thread::spawn(move || {
+    ///         let mut i = 0;
+    ///         loop {
+    ///             println!("sending: {i}");
+    ///             if sender.send(i).is_err() {
+    ///                 // Stop sending once `MyApp` is dropped
+    ///                 break;
+    ///             }
+    ///             // Trigger the wake-up _after_ we placed the event in the channel.
+    ///             // Otherwise, `proxy_wake_up` might be triggered prematurely.
+    ///             proxy.wake_up();
+    ///             i += 1;
+    ///             thread::sleep(Duration::from_secs(1));
+    ///         }
+    ///     });
+    ///
+    ///     event_loop.run_app(&mut app)?;
+    ///
+    ///     drop(app);
+    ///     background_thread.join().unwrap();
+    ///
+    ///     Ok(())
+    /// }
+    /// ```
+    fn proxy_wake_up(&mut self, event_loop: &dyn ActiveEventLoop) {
+        let _ = event_loop;
     }
 
     /// Emitted when the OS sends an event to a winit window.
     fn window_event(
         &mut self,
-        event_loop: &ActiveEventLoop,
+        event_loop: &dyn ActiveEventLoop,
         window_id: WindowId,
         event: WindowEvent,
     );
@@ -100,7 +197,7 @@ pub trait ApplicationHandler<T: 'static = ()> {
     /// Emitted when the OS sends an event to a device.
     fn device_event(
         &mut self,
-        event_loop: &ActiveEventLoop,
+        event_loop: &dyn ActiveEventLoop,
         device_id: DeviceId,
         event: DeviceEvent,
     ) {
@@ -118,31 +215,53 @@ pub trait ApplicationHandler<T: 'static = ()> {
     ///
     /// This is not an ideal event to drive application rendering from and instead applications
     /// should render in response to [`WindowEvent::RedrawRequested`] events.
-    fn about_to_wait(&mut self, event_loop: &ActiveEventLoop) {
+    fn about_to_wait(&mut self, event_loop: &dyn ActiveEventLoop) {
         let _ = event_loop;
     }
 
     /// Emitted when the application has been suspended.
     ///
-    /// # Portability
+    /// See [`resumed()`][Self::resumed].
     ///
-    /// Not all platforms support the notion of suspending applications, and there may be no
-    /// technical way to guarantee being able to emit a `Suspended` event if the OS has
-    /// no formal application lifecycle (currently only Android, iOS, and Web do). For this reason,
-    /// Winit does not currently try to emit pseudo `Suspended` events before the application
-    /// quits on platforms without an application lifecycle.
+    /// ## Platform-specific
     ///
-    /// Considering that the implementation of `Suspended` and [`Resumed`] events may be internally
-    /// driven by multiple platform-specific events, and that there may be subtle differences across
-    /// platforms with how these internal events are delivered, it's recommended that applications
-    /// be able to gracefully handle redundant (i.e. back-to-back) `Suspended` or [`Resumed`]
-    /// events.
+    /// ### iOS
     ///
-    /// Also see [`Resumed`] notes.
+    /// On iOS, the [`suspended()`] method is called in response to an
+    /// [`applicationWillResignActive`] callback which means that the application is about to
+    /// transition from the active to inactive state (according to the [iOS application lifecycle]).
     ///
-    /// ## Android
+    /// [`applicationWillResignActive`]: https://developer.apple.com/documentation/uikit/uiapplicationdelegate/1622950-applicationwillresignactive
+    /// [iOS application lifecycle]: https://developer.apple.com/documentation/uikit/app_and_environment/managing_your_app_s_life_cycle
     ///
-    /// On Android, the `Suspended` event is only sent when the application's associated
+    /// ### Web
+    ///
+    /// On Web, the [`suspended()`] method is called in response to a [`pagehide`] event if the
+    /// page is being restored from the [`bfcache`] (back/forward cache) - an in-memory cache that
+    /// stores a complete snapshot of a page (including the JavaScript heap) as the user is
+    /// navigating away.
+    ///
+    /// [`pagehide`]: https://developer.mozilla.org/en-US/docs/Web/API/Window/pagehide_event
+    /// [`bfcache`]: https://web.dev/bfcache/
+    ///
+    /// ### Others
+    ///
+    /// **Android / macOS / Orbital / Wayland / Windows / X11:** Unsupported.
+    ///
+    /// [`suspended()`]: Self::suspended
+    fn suspended(&mut self, event_loop: &dyn ActiveEventLoop) {
+        let _ = event_loop;
+    }
+
+    /// Emitted when the application must destroy its render surfaces.
+    ///
+    /// See [`can_create_surfaces()`] for more details.
+    ///
+    /// ## Platform-specific
+    ///
+    /// ### Android
+    ///
+    /// On Android, the [`destroy_surfaces()`] method is called when the application's associated
     /// [`SurfaceView`] is destroyed. This is expected to closely correlate with the [`onPause`]
     /// lifecycle event but there may technically be a discrepancy.
     ///
@@ -152,46 +271,32 @@ pub trait ApplicationHandler<T: 'static = ()> {
     /// destroyed, which indirectly invalidates any existing render surfaces that may have been
     /// created outside of Winit (such as an `EGLSurface`, [`VkSurfaceKHR`] or [`wgpu::Surface`]).
     ///
-    /// After being `Suspended` on Android applications must drop all render surfaces before
+    /// After being [suspended] on Android applications must drop all render surfaces before
     /// the event callback completes, which may be re-created when the application is next
-    /// [`Resumed`].
+    /// [resumed].
     ///
+    /// [suspended]: Self::destroy_surfaces
+    /// [resumed]: Self::can_create_surfaces
     /// [`SurfaceView`]: https://developer.android.com/reference/android/view/SurfaceView
     /// [Activity lifecycle]: https://developer.android.com/guide/components/activities/activity-lifecycle
     /// [`VkSurfaceKHR`]: https://www.khronos.org/registry/vulkan/specs/1.3-extensions/man/html/VkSurfaceKHR.html
     /// [`wgpu::Surface`]: https://docs.rs/wgpu/latest/wgpu/struct.Surface.html
     ///
-    /// ## iOS
+    /// ### Others
     ///
-    /// On iOS, the `Suspended` event is currently emitted in response to an
-    /// [`applicationWillResignActive`] callback which means that the application is
-    /// about to transition from the active to inactive state (according to the
-    /// [iOS application lifecycle]).
+    /// - **iOS / macOS / Orbital / Wayland / Web / Windows / X11:** Unsupported.
     ///
-    /// [`applicationWillResignActive`]: https://developer.apple.com/documentation/uikit/uiapplicationdelegate/1622950-applicationwillresignactive
-    /// [iOS application lifecycle]: https://developer.apple.com/documentation/uikit/app_and_environment/managing_your_app_s_life_cycle
-    ///
-    /// ## Web
-    ///
-    /// On Web, the `Suspended` event is emitted in response to a [`pagehide`] event
-    /// with the property [`persisted`] being true, which means that the page is being
-    /// put in the [`bfcache`] (back/forward cache) - an in-memory cache that stores a
-    /// complete snapshot of a page (including the JavaScript heap) as the user is
-    /// navigating away.
-    ///
-    /// [`pagehide`]: https://developer.mozilla.org/en-US/docs/Web/API/Window/pagehide_event
-    /// [`persisted`]: https://developer.mozilla.org/en-US/docs/Web/API/PageTransitionEvent/persisted
-    /// [`bfcache`]: https://web.dev/bfcache/
-    /// [`Resumed`]: Self::resumed
-    fn suspended(&mut self, event_loop: &ActiveEventLoop) {
+    /// [`can_create_surfaces()`]: Self::can_create_surfaces
+    /// [`destroy_surfaces()`]: Self::destroy_surfaces
+    fn destroy_surfaces(&mut self, event_loop: &dyn ActiveEventLoop) {
         let _ = event_loop;
     }
 
     /// Emitted when the event loop is being shut down.
     ///
     /// This is irreversible - if this method is called, it is guaranteed that the event loop
-    /// will exist right after.
-    fn exiting(&mut self, event_loop: &ActiveEventLoop) {
+    /// will exit right after.
+    fn exiting(&mut self, event_loop: &dyn ActiveEventLoop) {
         let _ = event_loop;
     }
 
@@ -219,7 +324,161 @@ pub trait ApplicationHandler<T: 'static = ()> {
     /// ### Others
     ///
     /// - **macOS / Orbital / Wayland / Web / Windows:** Unsupported.
-    fn memory_warning(&mut self, event_loop: &ActiveEventLoop) {
+    fn memory_warning(&mut self, event_loop: &dyn ActiveEventLoop) {
         let _ = event_loop;
     }
+
+    /// Get the [`ApplicationHandler`] as [`Any`].
+    ///
+    /// This is useful for downcasting to a concrete application type.
+    #[inline(always)]
+    fn as_any(&mut self) -> Option<&mut dyn Any> {
+        None
+    }
+}
+
+#[deny(clippy::missing_trait_methods)]
+impl<A: ?Sized + ApplicationHandler> ApplicationHandler for &mut A {
+    #[inline(always)]
+    fn as_any(&mut self) -> Option<&mut dyn Any> {
+        (**self).as_any()
+    }
+
+    #[inline]
+    fn new_events(&mut self, event_loop: &dyn ActiveEventLoop, cause: StartCause) {
+        (**self).new_events(event_loop, cause);
+    }
+
+    #[inline]
+    fn resumed(&mut self, event_loop: &dyn ActiveEventLoop) {
+        (**self).resumed(event_loop);
+    }
+
+    #[inline]
+    fn can_create_surfaces(&mut self, event_loop: &dyn ActiveEventLoop) {
+        (**self).can_create_surfaces(event_loop);
+    }
+
+    #[inline]
+    fn proxy_wake_up(&mut self, event_loop: &dyn ActiveEventLoop) {
+        (**self).proxy_wake_up(event_loop);
+    }
+
+    #[inline]
+    fn window_event(
+        &mut self,
+        event_loop: &dyn ActiveEventLoop,
+        window_id: WindowId,
+        event: WindowEvent,
+    ) {
+        (**self).window_event(event_loop, window_id, event);
+    }
+
+    #[inline]
+    fn device_event(
+        &mut self,
+        event_loop: &dyn ActiveEventLoop,
+        device_id: DeviceId,
+        event: DeviceEvent,
+    ) {
+        (**self).device_event(event_loop, device_id, event);
+    }
+
+    #[inline]
+    fn about_to_wait(&mut self, event_loop: &dyn ActiveEventLoop) {
+        (**self).about_to_wait(event_loop);
+    }
+
+    #[inline]
+    fn suspended(&mut self, event_loop: &dyn ActiveEventLoop) {
+        (**self).suspended(event_loop);
+    }
+
+    #[inline]
+    fn destroy_surfaces(&mut self, event_loop: &dyn ActiveEventLoop) {
+        (**self).destroy_surfaces(event_loop);
+    }
+
+    #[inline]
+    fn exiting(&mut self, event_loop: &dyn ActiveEventLoop) {
+        (**self).exiting(event_loop);
+    }
+
+    #[inline]
+    fn memory_warning(&mut self, event_loop: &dyn ActiveEventLoop) {
+        (**self).memory_warning(event_loop);
+    }
+}
+
+#[deny(clippy::missing_trait_methods)]
+impl<A: ?Sized + ApplicationHandler> ApplicationHandler for Box<A> {
+    #[inline(always)]
+    fn as_any(&mut self) -> Option<&mut dyn Any> {
+        (**self).as_any()
+    }
+
+    #[inline]
+    fn new_events(&mut self, event_loop: &dyn ActiveEventLoop, cause: StartCause) {
+        (**self).new_events(event_loop, cause);
+    }
+
+    #[inline]
+    fn resumed(&mut self, event_loop: &dyn ActiveEventLoop) {
+        (**self).resumed(event_loop);
+    }
+
+    #[inline]
+    fn can_create_surfaces(&mut self, event_loop: &dyn ActiveEventLoop) {
+        (**self).can_create_surfaces(event_loop);
+    }
+
+    #[inline]
+    fn proxy_wake_up(&mut self, event_loop: &dyn ActiveEventLoop) {
+        (**self).proxy_wake_up(event_loop);
+    }
+
+    #[inline]
+    fn window_event(
+        &mut self,
+        event_loop: &dyn ActiveEventLoop,
+        window_id: WindowId,
+        event: WindowEvent,
+    ) {
+        (**self).window_event(event_loop, window_id, event);
+    }
+
+    #[inline]
+    fn device_event(
+        &mut self,
+        event_loop: &dyn ActiveEventLoop,
+        device_id: DeviceId,
+        event: DeviceEvent,
+    ) {
+        (**self).device_event(event_loop, device_id, event);
+    }
+
+    #[inline]
+    fn about_to_wait(&mut self, event_loop: &dyn ActiveEventLoop) {
+        (**self).about_to_wait(event_loop);
+    }
+
+    #[inline]
+    fn suspended(&mut self, event_loop: &dyn ActiveEventLoop) {
+        (**self).suspended(event_loop);
+    }
+
+    #[inline]
+    fn destroy_surfaces(&mut self, event_loop: &dyn ActiveEventLoop) {
+        (**self).destroy_surfaces(event_loop);
+    }
+
+    #[inline]
+    fn exiting(&mut self, event_loop: &dyn ActiveEventLoop) {
+        (**self).exiting(event_loop);
+    }
+
+    #[inline]
+    fn memory_warning(&mut self, event_loop: &dyn ActiveEventLoop) {
+        (**self).memory_warning(event_loop);
+    }
 }

src/changelog/unreleased.md

@@ -39,3 +39,94 @@ The migration guide could reference other migration examples in the current
 changelog entry.
 
 ## Unreleased
+
+### Added
+
+- Add `ActiveEventLoop::create_proxy()`.
+- On Web, implement `Error` for `platform::web::CustomCursorError`.
+- On Web, add `ActiveEventLoopExtWeb::is_cursor_lock_raw()` to determine if
+  `DeviceEvent::MouseMotion` is returning raw data, not OS accelerated, when using
+  `CursorGrabMode::Locked`.
+- On Web, implement `MonitorHandle` and `VideoModeHandle`.
+  
+  Without prompting the user for permission, only the current monitor is returned. But when
+  prompting and being granted permission through
+  `ActiveEventLoop::request_detailed_monitor_permission()`, access to all monitors and their
+  information is available. This "detailed monitors" can be used in `Window::set_fullscreen()` as
+  well.
+- On Android, add `{Active,}EventLoopExtAndroid::android_app()` to access the app used to create the loop.
+- Add `ActiveEventLoop::system_theme()`, returning the current system theme.
+- Add `Touch::finger_id` with a new type `FingerId`.
+- On Web and Windows, add `FingerIdExt*::is_primary()`, exposing a way to determine
+  the primary finger in a multi-touch interaction.
+- Implement `Clone`, `Copy`, `Debug`, `Deserialize`, `Eq`, `Hash`, `Ord`, `PartialEq`, `PartialOrd`
+  and `Serialize` on many types.
+- Add `MonitorHandle::current_video_mode()`.
+
+### Changed
+
+- Change `ActiveEventLoop` to be a trait.
+- `ApplicationHandler` now uses `dyn ActiveEventLoop`.
+- On Web, let events wake up event loop immediately when using `ControlFlow::Poll`.
+- Bump MSRV from `1.70` to `1.73`.
+- Changed `ApplicationHandler::user_event` to `user_wake_up`, removing the
+  generic user event.
+
+  Winit will now only indicate that wake up happened, you will have to pair
+  this with an external mechanism like `std::sync::mpsc::channel` if you want
+  to send specific data to be processed on the main thread.
+- Changed `EventLoopProxy::send_event` to `EventLoopProxy::wake_up`, it now
+  only wakes up the loop.
+- On X11, implement smooth resizing through the sync extension API.
+- `ApplicationHandler::create|destroy_surfaces()` was split off from
+  `ApplicationHandler::resumed/suspended()`.
+
+  `ApplicationHandler::can_create_surfaces()` should, for portability reasons
+  to Android, be the only place to create render surfaces.
+
+  `ApplicationHandler::resumed/suspended()` are now only emitted by iOS and Web
+  and now signify actually resuming/suspending the application.
+- Rename `platform::web::*ExtWebSys` to `*ExtWeb`.
+- Change signature of `EventLoop::run_app`, `EventLoopExtPumpEvents::pump_app_events` and
+  `EventLoopExtRunOnDemand::run_app_on_demand` to accept a `impl ApplicationHandler` directly,
+  instead of requiring a `&mut` reference to it.
+- On Web, `Window::canvas()` now returns a reference.
+- On Web, `CursorGrabMode::Locked` now lets `DeviceEvent::MouseMotion` return raw data, not OS
+  accelerated, if the browser supports it.
+- `(Active)EventLoop::create_custom_cursor()` now returns a `Result<CustomCursor, ExternalError>`.
+- Changed how `ModifiersState` is serialized by Serde.
+- `VideoModeHandle::refresh_rate_millihertz()` and `bit_depth()` now return a `Option<NonZero*>`.
+- `MonitorHandle::position()` now returns an `Option`.
+
+### Removed
+
+- Remove `Event`.
+- Remove already deprecated APIs:
+  - `EventLoop::create_window()`
+  - `EventLoop::run`.
+  - `EventLoopBuilder::new()`
+  - `EventLoopExtPumpEvents::pump_events`.
+  - `EventLoopExtRunOnDemand::run_on_demand`.
+  - `VideoMode`
+  - `WindowAttributes::new()`
+  - `Window::set_cursor_icon()`
+- On iOS, remove `platform::ios::EventLoopExtIOS` and related `platform::ios::Idiom` type.
+
+  This feature was incomplete, and the equivalent functionality can be trivially achieved outside
+  of `winit` using `objc2-ui-kit` and calling `UIDevice::currentDevice().userInterfaceIdiom()`.
+- On Web, remove unused `platform::web::CustomCursorError::Animation`.
+- Remove the `rwh_04` and `rwh_05` cargo feature and the corresponding `raw-window-handle` v0.4 and
+  v0.5 support. v0.6 remains in place and is enabled by default.
+- Remove `DeviceEvent::Added` and `DeviceEvent::Removed`.
+- Remove `DeviceEvent::Motion` and `WindowEvent::AxisMotion`.
+- Remove `Touch::id` in favor of `Touch::finger_id`.
+- Remove `MonitorHandle::size()` and `refresh_rate_millihertz()` in favor of
+  `MonitorHandle::current_video_mode()`.
+- On Android, remove all `MonitorHandle` support instead of emitting false data.
+
+### Fixed
+
+- On Web, pen events are now routed through to `WindowEvent::Cursor*`.
+- On macOS, fix panic when releasing not available monitor.
+- On MacOS, return the system theme in `Window::theme()` if no theme override is set.
+- On Orbital, `MonitorHandle::name()` now returns `None` instead of a dummy name.

src/changelog/v0.20.md

@@ -137,7 +137,7 @@
 
 - On X11, non-resizable windows now have maximize explicitly disabled.
 - On Windows, support paths longer than MAX_PATH (260 characters) in `WindowEvent::DroppedFile`
-and `WindowEvent::HoveredFile`.
+  and `WindowEvent::HoveredFile`.
 - On Mac, implement `DeviceEvent::Button`.
 - Change `Event::Suspended(true / false)` to `Event::Suspended` and `Event::Resumed`.
 - On X11, fix sanity check which checks that a monitor's reported width and height (in millimeters) are non-zero when calculating the DPI factor.

src/changelog/v0.30.md

@@ -1,3 +1,64 @@
+## 0.30.4
+
+### Changed
+
+- `DeviceId::dummy()` and `WindowId::dummy()` are no longer marked `unsafe`.
+
+### Fixed
+
+- On Wayland, avoid crashing when compositor is misbehaving.
+- On Web, fix `WindowEvent::Resized` not using `requestAnimationFrame` when sending
+  `WindowEvent::RedrawRequested` and also potentially causing `WindowEvent::RedrawRequested`
+  to not be de-duplicated.
+- Account for different browser engine implementations of pointer movement coordinate space.
+
+## 0.30.3
+
+### Added
+
+- On Web, add `EventLoopExtWebSys::(set_)poll_strategy()` to allow setting
+  control flow strategies before starting the event loop.
+- On Web, add `WaitUntilStrategy`, which allows to set different strategies for
+  `ControlFlow::WaitUntil`. By default the Prioritized Task Scheduling API is
+  used, with a fallback to `setTimeout()` with a trick to circumvent throttling
+  to 4ms. But an option to use a Web worker to schedule the timer is available
+  as well, which commonly prevents any throttling when the window is not focused.
+
+### Changed
+
+- On macOS, set the window theme on the `NSWindow` instead of application-wide.
+
+### Fixed
+
+- On X11, build on arm platforms.
+- On macOS, fixed `WindowBuilder::with_theme` not having any effect on the window.
+
+## 0.30.2
+
+### Fixed
+
+- On Web, fix `EventLoopProxy::send_event()` triggering event loop immediately
+  when not called from inside the event loop. Now queues a microtask instead.
+- On Web, stop overwriting default cursor with `CursorIcon::Default`.
+- On Web, prevent crash when using `InnerSizeWriter::request_inner_size()`.
+- On macOS, fix not working opacity for entire window.
+
+## 0.30.1
+
+### Added
+
+- Reexport `raw-window-handle` versions 0.4 and 0.5 as `raw_window_handle_04` and `raw_window_handle_05`.
+- Implement `ApplicationHandler` for `&mut` references and heap allocations to something that implements `ApplicationHandler`.
+- Add traits `EventLoopExtWayland` and `EventLoopExtX11`, providing methods `is_wayland` and `is_x11` on `EventLoop`.
+
+### Fixed
+
+- On macOS, fix panic on exit when dropping windows outside the event loop.
+- On macOS, fix window dragging glitches when dragging across a monitor boundary with different scale factor.
+- On macOS, fix the range in `Ime::Preedit`.
+- On macOS, use the system's internal mechanisms for queuing events.
+- On macOS, handle events directly instead of queuing when possible.
+
 ## 0.30.0
 
 ### Added
@@ -65,7 +126,7 @@
   `Fn`. The semantics are mostly the same, given that the capture list of the
   closure is your new `State`. Consider the following code:
 
-  ```rust,no_run
+  ```rust,no_run,ignore
   use winit::event::Event;
   use winit::event_loop::EventLoop;
   use winit::window::Window;
@@ -101,7 +162,7 @@
   we move particular `match event` arms into methods on `ApplicationHandler`,
   for example:
 
-  ```rust,no_run
+  ```rust,no_run,ignore
   use winit::application::ApplicationHandler;
   use winit::event::{Event, WindowEvent, DeviceEvent, DeviceId};
   use winit::event_loop::{EventLoop, ActiveEventLoop};
@@ -164,7 +225,7 @@
 
   Using the migration example from above, you can change your code as follows:
 
-  ```rust,no_run
+  ```rust,no_run,ignore
   use winit::application::ApplicationHandler;
   use winit::event::{Event, WindowEvent, DeviceEvent, DeviceId};
   use winit::event_loop::{EventLoop, ActiveEventLoop};

src/changelog/v0.9.md

@@ -3,20 +3,20 @@
 - Added event `WindowEvent::HiDPIFactorChanged`.
 - Added method `MonitorId::get_hidpi_factor`.
 - Deprecated `get_inner_size_pixels` and `get_inner_size_points` methods of `Window` in favor of
-`get_inner_size`.
+  `get_inner_size`.
 - **Breaking:** `EventsLoop` is `!Send` and `!Sync` because of platform-dependant constraints,
   but `Window`, `WindowId`, `DeviceId` and `MonitorId` guaranteed to be `Send`.
 - `MonitorId::get_position` now returns `(i32, i32)` instead of `(u32, u32)`.
 - Rewrite of the wayland backend to use wayland-client-0.11
 - Support for dead keys on wayland for keyboard utf8 input
 - Monitor enumeration on Windows is now implemented using `EnumDisplayMonitors` instead of
-`EnumDisplayDevices`. This changes the value returned by `MonitorId::get_name()`.
+  `EnumDisplayDevices`. This changes the value returned by `MonitorId::get_name()`.
 - On Windows added `MonitorIdExt::hmonitor` method
 - Impl `Clone` for `EventsLoopProxy`
 - `EventsLoop::get_primary_monitor()` on X11 will fallback to any available monitor if no primary is found
 - Support for touch event on wayland
 - `WindowEvent`s `MouseMoved`, `MouseEntered`, and `MouseLeft` have been renamed to
-`CursorMoved`, `CursorEntered`, and `CursorLeft`.
+  `CursorMoved`, `CursorEntered`, and `CursorLeft`.
 - New `DeviceEvent`s added, `MouseMotion` and `MouseWheel`.
 - Send `CursorMoved` event after `CursorEntered` and `Focused` events.
 - Add support for `ModifiersState`, `MouseMove`, `MouseInput`, `MouseMotion` for emscripten backend.

src/cursor.rs

@@ -50,7 +50,7 @@ impl From<CustomCursor> for Cursor {
 /// ```no_run
 /// # use winit::event_loop::ActiveEventLoop;
 /// # use winit::window::Window;
-/// # fn scope(event_loop: &ActiveEventLoop, window: &Window) {
+/// # fn scope(event_loop: &dyn ActiveEventLoop, window: &Window) {
 /// use winit::window::CustomCursor;
 ///
 /// let w = 10;
@@ -62,13 +62,13 @@ impl From<CustomCursor> for Cursor {
 ///
 /// #[cfg(target_family = "wasm")]
 /// let source = {
-///     use winit::platform::web::CustomCursorExtWebSys;
+///     use winit::platform::web::CustomCursorExtWeb;
 ///     CustomCursor::from_url(String::from("http://localhost:3000/cursor.png"), 0, 0)
 /// };
 ///
-/// let custom_cursor = event_loop.create_custom_cursor(source);
-///
-/// window.set_cursor(custom_cursor.clone());
+/// if let Ok(custom_cursor) = event_loop.create_custom_cursor(source) {
+///     window.set_cursor(custom_cursor.clone());
+/// }
 /// # }
 /// ```
 #[derive(Clone, Debug, Eq, Hash, PartialEq)]
@@ -107,13 +107,16 @@ impl CustomCursor {
 /// Source for [`CustomCursor`].
 ///
 /// See [`CustomCursor`] for more details.
-#[derive(Debug)]
+#[derive(Debug, Clone, Eq, Hash, PartialEq)]
 pub struct CustomCursorSource {
+    // Some platforms don't support custom cursors.
+    #[allow(dead_code)]
     pub(crate) inner: PlatformCustomCursorSource,
 }
 
 /// An error produced when using [`CustomCursor::from_rgba`] with invalid arguments.
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 pub enum BadImage {
     /// Produced when the image dimensions are larger than [`MAX_CURSOR_SIZE`]. This doesn't
     /// guarantee that the cursor will work, but should avoid many platform and device specific
@@ -164,7 +167,7 @@ impl Error for BadImage {}
 /// Platforms export this directly as `PlatformCustomCursorSource` if they need to only work with
 /// images.
 #[allow(dead_code)]
-#[derive(Debug)]
+#[derive(Debug, Clone, Eq, Hash, PartialEq)]
 pub(crate) struct OnlyCursorImageSource(pub(crate) CursorImage);
 
 #[allow(dead_code)]
@@ -199,7 +202,7 @@ impl PartialEq for OnlyCursorImage {
 
 impl Eq for OnlyCursorImage {}
 
-#[derive(Debug)]
+#[derive(Debug, Clone, Eq, Hash, PartialEq)]
 #[allow(dead_code)]
 pub(crate) struct CursorImage {
     pub(crate) rgba: Vec<u8>,

src/error.rs

@@ -15,7 +15,8 @@ pub enum ExternalError {
 }
 
 /// The error type for when the requested operation is not supported by the backend.
-#[derive(Clone)]
+#[derive(Clone, Copy, Default, Eq, Hash, PartialEq)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 pub struct NotSupportedError {
     _marker: (),
 }

src/event.rs

@@ -1,4 +1,4 @@
-//! The [`Event`] enum and assorted supporting types.
+//! The event enums and assorted supporting types.
 //!
 //! These are sent to the closure given to [`EventLoop::run_app(...)`], where they get
 //! processed and used to modify the program state. For more details, see the root-level
@@ -54,11 +54,15 @@ use crate::platform_impl;
 use crate::window::Window;
 use crate::window::{ActivationToken, Theme, WindowId};
 
+// TODO: Remove once the backends can call `ApplicationHandler` methods directly. For now backends
+// like Windows and Web require `Event` to wire user events, otherwise each backend will have to
+// wrap `Event` in some other structure.
 /// Describes a generic event.
 ///
 /// See the module-level docs for more information on the event loop manages each event.
+#[allow(dead_code)]
 #[derive(Debug, Clone, PartialEq)]
-pub enum Event<T: 'static> {
+pub(crate) enum Event {
     /// See [`ApplicationHandler::new_events`] for details.
     ///
     /// [`ApplicationHandler::new_events`]: crate::application::ApplicationHandler::new_events
@@ -67,23 +71,25 @@ pub enum Event<T: 'static> {
     /// See [`ApplicationHandler::window_event`] for details.
     ///
     /// [`ApplicationHandler::window_event`]: crate::application::ApplicationHandler::window_event
+    #[allow(clippy::enum_variant_names)]
     WindowEvent { window_id: WindowId, event: WindowEvent },
 
     /// See [`ApplicationHandler::device_event`] for details.
     ///
     /// [`ApplicationHandler::device_event`]: crate::application::ApplicationHandler::device_event
+    #[allow(clippy::enum_variant_names)]
     DeviceEvent { device_id: DeviceId, event: DeviceEvent },
 
-    /// See [`ApplicationHandler::user_event`] for details.
-    ///
-    /// [`ApplicationHandler::user_event`]: crate::application::ApplicationHandler::user_event
-    UserEvent(T),
-
     /// See [`ApplicationHandler::suspended`] for details.
     ///
     /// [`ApplicationHandler::suspended`]: crate::application::ApplicationHandler::suspended
     Suspended,
 
+    /// See [`ApplicationHandler::can_create_surfaces`] for details.
+    ///
+    /// [`ApplicationHandler::can_create_surfaces`]: crate::application::ApplicationHandler::can_create_surfaces
+    CreateSurfaces,
+
     /// See [`ApplicationHandler::resumed`] for details.
     ///
     /// [`ApplicationHandler::resumed`]: crate::application::ApplicationHandler::resumed
@@ -103,28 +109,13 @@ pub enum Event<T: 'static> {
     ///
     /// [`ApplicationHandler::memory_warning`]: crate::application::ApplicationHandler::memory_warning
     MemoryWarning,
-}
 
-impl<T> Event<T> {
-    #[allow(clippy::result_large_err)]
-    pub fn map_nonuser_event<U>(self) -> Result<Event<U>, Event<T>> {
-        use self::Event::*;
-        match self {
-            UserEvent(_) => Err(self),
-            WindowEvent { window_id, event } => Ok(WindowEvent { window_id, event }),
-            DeviceEvent { device_id, event } => Ok(DeviceEvent { device_id, event }),
-            NewEvents(cause) => Ok(NewEvents(cause)),
-            AboutToWait => Ok(AboutToWait),
-            LoopExiting => Ok(LoopExiting),
-            Suspended => Ok(Suspended),
-            Resumed => Ok(Resumed),
-            MemoryWarning => Ok(MemoryWarning),
-        }
-    }
+    /// User requested a wake up.
+    UserWakeUp,
 }
 
 /// Describes the reason the event loop is resuming.
-#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
 pub enum StartCause {
     /// Sent if the time specified by [`ControlFlow::WaitUntil`] has been reached. Contains the
     /// moment the timeout was requested and the requested resume time. The actual resume time is
@@ -349,9 +340,6 @@ pub enum WindowEvent {
     /// touchpad is being pressed) and stage (integer representing the click level).
     TouchpadPressure { device_id: DeviceId, pressure: f32, stage: i64 },
 
-    /// Motion on some analog axis. May report data redundant to other, more specific events.
-    AxisMotion { device_id: DeviceId, axis: AxisId, value: f64 },
-
     /// Touch event has been received
     ///
     /// ## Platform-specific
@@ -389,6 +377,8 @@ pub enum WindowEvent {
     /// Applications might wish to react to this to change the theme of the content of the window
     /// when the system changes the window theme.
     ///
+    /// This only reports a change if the window theme was not overridden by [`Window::set_theme`].
+    ///
     /// ## Platform-specific
     ///
     /// - **iOS / Android / X11 / Wayland / Orbital:** Unsupported.
@@ -444,19 +434,42 @@ pub enum WindowEvent {
 #[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub struct DeviceId(pub(crate) platform_impl::DeviceId);
 
+impl Default for DeviceId {
+    fn default() -> Self {
+        Self::dummy()
+    }
+}
+
 impl DeviceId {
     /// Returns a dummy id, useful for unit testing.
     ///
-    /// # Safety
+    /// # Notes
     ///
     /// The only guarantee made about the return value of this function is that
     /// it will always be equal to itself and to future values returned by this function.
     /// No other guarantees are made. This may be equal to a real `DeviceId`.
+    pub const fn dummy() -> Self {
+        DeviceId(platform_impl::DeviceId::dummy())
+    }
+}
+
+/// Identifier of a finger in a touch event.
+///
+/// Whenever a touch event is received it contains a `FingerId` which uniquely identifies the finger
+/// used for the current interaction.
+#[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub struct FingerId(pub(crate) platform_impl::FingerId);
+
+impl FingerId {
+    /// Returns a dummy id, useful for unit testing.
     ///
-    /// **Passing this into a winit function will result in undefined behavior.**
-    pub const unsafe fn dummy() -> Self {
-        #[allow(unused_unsafe)]
-        DeviceId(unsafe { platform_impl::DeviceId::dummy() })
+    /// # Notes
+    ///
+    /// The only guarantee made about the return value of this function is that
+    /// it will always be equal to itself and to future values returned by this function.
+    /// No other guarantees are made. This may be equal to a real `FingerId`.
+    pub const fn dummy() -> Self {
+        FingerId(platform_impl::FingerId::dummy())
     }
 }
 
@@ -468,15 +481,28 @@ impl DeviceId {
 /// (corresponding to GUI cursors and keyboard focus) the device IDs may not match.
 ///
 /// Note that these events are delivered regardless of input focus.
-#[derive(Clone, Debug, PartialEq)]
+#[derive(Clone, Copy, Debug, PartialEq)]
 pub enum DeviceEvent {
-    Added,
-    Removed,
-
     /// Change in physical position of a pointing device.
     ///
     /// This represents raw, unfiltered physical motion. Not to be confused with
     /// [`WindowEvent::CursorMoved`].
+    ///
+    /// ## Platform-specific
+    ///
+    /// **Web:** Only returns raw data, not OS accelerated, if [`CursorGrabMode::Locked`] is used
+    /// and browser support is available, see
+    #[cfg_attr(
+        any(web_platform, docsrs),
+        doc = "[`ActiveEventLoopExtWeb::is_cursor_lock_raw()`][crate::platform::web::ActiveEventLoopExtWeb::is_cursor_lock_raw()]."
+    )]
+    #[cfg_attr(
+        not(any(web_platform, docsrs)),
+        doc = "`ActiveEventLoopExtWeb::is_cursor_lock_raw()`."
+    )]
+    ///
+    #[rustfmt::skip]
+    /// [`CursorGrabMode::Locked`]: crate::window::CursorGrabMode::Locked
     MouseMotion {
         /// (x, y) change in position in unspecified units.
         ///
@@ -489,14 +515,6 @@ pub enum DeviceEvent {
         delta: MouseScrollDelta,
     },
 
-    /// Motion on some analog axis. This event will be reported for all arbitrary input devices
-    /// that winit supports on this platform, including mouse devices.  If the device is a mouse
-    /// device then this will be reported alongside the MouseMotion event.
-    Motion {
-        axis: AxisId,
-        value: f64,
-    },
-
     Button {
         button: ButtonId,
         state: ElementState,
@@ -512,7 +530,7 @@ pub enum DeviceEvent {
 /// repeat or the initial keypress. An application may emulate this by, for
 /// example keeping a Map/Set of pressed keys and determining whether a keypress
 /// corresponds to an already pressed key.
-#[derive(Debug, Clone, Eq, PartialEq, Hash)]
+#[derive(Debug, Clone, Copy, Eq, PartialEq, Hash)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 pub struct RawKeyEvent {
     pub physical_key: keyboard::PhysicalKey,
@@ -533,11 +551,11 @@ pub struct KeyEvent {
     /// ## Caveats
     ///
     /// - Certain niche hardware will shuffle around physical key positions, e.g. a keyboard that
-    /// implements DVORAK in hardware (or firmware)
+    ///   implements DVORAK in hardware (or firmware)
     /// - Your application will likely have to handle keyboards which are missing keys that your
-    /// own keyboard has.
+    ///   own keyboard has.
     /// - Certain `KeyCode`s will move between a couple of different positions depending on what
-    /// layout the keyboard was manufactured to support.
+    ///   layout the keyboard was manufactured to support.
     ///
     ///  **Because of these caveats, it is important that you provide users with a way to configure
     ///  most (if not all) keybinds in your application.**
@@ -559,8 +577,7 @@ pub struct KeyEvent {
     ///
     /// This has two use cases:
     /// - Allows querying whether the current input is a Dead key.
-    /// - Allows handling key-bindings on platforms which don't
-    /// support [`key_without_modifiers`].
+    /// - Allows handling key-bindings on platforms which don't support [`key_without_modifiers`].
     ///
     /// If you use this field (or [`key_without_modifiers`] for that matter) for keyboard
     /// shortcuts, **it is important that you provide users with a way to configure your
@@ -568,8 +585,8 @@ pub struct KeyEvent {
     /// incompatible keyboard layout.**
     ///
     /// ## Platform-specific
-    /// - **Web:** Dead keys might be reported as the real key instead
-    /// of `Dead` depending on the browser/OS.
+    /// - **Web:** Dead keys might be reported as the real key instead of `Dead` depending on the
+    ///   browser/OS.
     ///
     /// [`key_without_modifiers`]: crate::platform::modifier_supplement::KeyEventExtModifierSupplement::key_without_modifiers
     pub logical_key: keyboard::Key,
@@ -626,7 +643,7 @@ pub struct KeyEvent {
     /// In games, you often want to ignore repated key events - this can be
     /// done by ignoring events where this property is set.
     ///
-    /// ```
+    /// ```no_run
     /// use winit::event::{ElementState, KeyEvent, WindowEvent};
     /// use winit::keyboard::{KeyCode, PhysicalKey};
     /// # let window_event = WindowEvent::RedrawRequested; // To make the example compile
@@ -658,7 +675,8 @@ pub struct KeyEvent {
 }
 
 /// Describes keyboard modifiers event.
-#[derive(Debug, Default, Clone, Copy, PartialEq, Eq)]
+#[derive(Debug, Default, Clone, Copy, PartialEq, Eq, Hash)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 pub struct Modifiers {
     pub(crate) state: ModifiersState,
 
@@ -851,15 +869,16 @@ pub struct Touch {
     ///
     /// - Only available on **iOS** 9.0+, **Windows** 8+, **Web**, and **Android**.
     /// - **Android**: This will never be [None]. If the device doesn't support pressure
-    /// sensitivity, force will either be 0.0 or 1.0. Also see the
-    /// [android documentation](https://developer.android.com/reference/android/view/MotionEvent#AXIS_PRESSURE).
+    ///   sensitivity, force will either be 0.0 or 1.0. Also see the
+    ///   [android documentation](https://developer.android.com/reference/android/view/MotionEvent#AXIS_PRESSURE).
     pub force: Option<Force>,
     /// Unique identifier of a finger.
-    pub id: u64,
+    pub finger_id: FingerId,
 }
 
 /// Describes the force of a touch event
 #[derive(Debug, Clone, Copy, PartialEq)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 pub enum Force {
     /// On iOS, the force is calibrated so that the same number corresponds to
     /// roughly the same amount of pressure on the screen regardless of the
@@ -1009,17 +1028,21 @@ impl PartialEq for InnerSizeWriter {
     }
 }
 
+impl Eq for InnerSizeWriter {}
+
 #[cfg(test)]
 mod tests {
+    use std::collections::{BTreeSet, HashSet};
+
     use crate::dpi::PhysicalPosition;
     use crate::event;
-    use std::collections::{BTreeSet, HashSet};
 
     macro_rules! foreach_event {
         ($closure:expr) => {{
             #[allow(unused_mut)]
             let mut x = $closure;
-            let did = unsafe { event::DeviceId::dummy() };
+            let did = event::DeviceId::dummy();
+            let fid = event::FingerId::dummy();
 
             #[allow(deprecated)]
             {
@@ -1029,8 +1052,7 @@ mod tests {
                 use crate::window::WindowId;
 
                 // Mainline events.
-                let wid = unsafe { WindowId::dummy() };
-                x(UserEvent(()));
+                let wid = WindowId::dummy();
                 x(NewEvents(event::StartCause::Init));
                 x(AboutToWait);
                 x(LoopExiting);
@@ -1080,12 +1102,11 @@ mod tests {
                     phase: event::TouchPhase::Started,
                 });
                 with_window_event(TouchpadPressure { device_id: did, pressure: 0.0, stage: 0 });
-                with_window_event(AxisMotion { device_id: did, axis: 0, value: 0.0 });
                 with_window_event(Touch(event::Touch {
                     device_id: did,
                     phase: event::TouchPhase::Started,
                     location: (0.0, 0.0).into(),
-                    id: 0,
+                    finger_id: fid,
                     force: Some(event::Force::Normalized(0.0)),
                 }));
                 with_window_event(ThemeChanged(crate::window::Theme::Light));
@@ -1099,13 +1120,10 @@ mod tests {
                 let with_device_event =
                     |dev_ev| x(event::Event::DeviceEvent { device_id: did, event: dev_ev });
 
-                with_device_event(Added);
-                with_device_event(Removed);
                 with_device_event(MouseMotion { delta: (0.0, 0.0).into() });
                 with_device_event(MouseWheel {
                     delta: event::MouseScrollDelta::LineDelta(0.0, 0.0),
                 });
-                with_device_event(Motion { axis: 0, value: 0.0 });
                 with_device_event(Button { button: 0, state: event::ElementState::Pressed });
             }
         }};
@@ -1114,25 +1132,12 @@ mod tests {
     #[allow(clippy::redundant_clone)]
     #[test]
     fn test_event_clone() {
-        foreach_event!(|event: event::Event<()>| {
+        foreach_event!(|event: event::Event| {
             let event2 = event.clone();
             assert_eq!(event, event2);
         })
     }
 
-    #[test]
-    fn test_map_nonuser_event() {
-        foreach_event!(|event: event::Event<()>| {
-            let is_user = matches!(event, event::Event::UserEvent(()));
-            let event2 = event.map_nonuser_event::<()>();
-            if is_user {
-                assert_eq!(event2, Err(event::Event::UserEvent(())));
-            } else {
-                assert!(event2.is_ok());
-            }
-        })
-    }
-
     #[test]
     fn test_force_normalize() {
         let force = event::Force::Normalized(0.0);
@@ -1153,12 +1158,13 @@ mod tests {
     #[allow(clippy::clone_on_copy)]
     #[test]
     fn ensure_attrs_do_not_panic() {
-        foreach_event!(|event: event::Event<()>| {
+        foreach_event!(|event: event::Event| {
             let _ = format!("{:?}", event);
         });
         let _ = event::StartCause::Init.clone();
 
-        let did = unsafe { crate::event::DeviceId::dummy() }.clone();
+        let did = crate::event::DeviceId::dummy().clone();
+        let fid = crate::event::FingerId::dummy().clone();
         HashSet::new().insert(did);
         let mut set = [did, did, did];
         set.sort_unstable();
@@ -1174,7 +1180,7 @@ mod tests {
             device_id: did,
             phase: event::TouchPhase::Started,
             location: (0.0, 0.0).into(),
-            id: 0,
+            finger_id: fid,
             force: Some(event::Force::Normalized(0.0)),
         }
         .clone();

src/event_loop.rs

@@ -3,27 +3,28 @@
 //!
 //! If you want to send custom events to the event loop, use
 //! [`EventLoop::create_proxy`] to acquire an [`EventLoopProxy`] and call its
-//! [`send_event`][EventLoopProxy::send_event] method.
+//! [`wake_up`][EventLoopProxy::wake_up] method. Then during handling the wake up
+//! you can poll your event sources.
 //!
 //! See the root-level documentation for information on how to create and use an event loop to
 //! handle events.
+use std::any::Any;
+use std::fmt;
 use std::marker::PhantomData;
 #[cfg(any(x11_platform, wayland_platform))]
 use std::os::unix::io::{AsFd, AsRawFd, BorrowedFd, RawFd};
 use std::sync::atomic::{AtomicBool, AtomicUsize, Ordering};
-use std::{error, fmt};
-
 #[cfg(not(web_platform))]
 use std::time::{Duration, Instant};
+
 #[cfg(web_platform)]
 use web_time::{Duration, Instant};
 
 use crate::application::ApplicationHandler;
-use crate::error::{EventLoopError, OsError};
-use crate::event::Event;
+use crate::error::{EventLoopError, ExternalError, OsError};
 use crate::monitor::MonitorHandle;
 use crate::platform_impl;
-use crate::window::{CustomCursor, CustomCursorSource, Window, WindowAttributes};
+use crate::window::{CustomCursor, CustomCursorSource, Theme, Window, WindowAttributes};
 
 /// Provides a way to retrieve events from the system and from the windows that were registered to
 /// the events loop.
@@ -40,17 +41,8 @@ use crate::window::{CustomCursor, CustomCursorSource, Window, WindowAttributes};
 /// [`EventLoopProxy`] allows you to wake up an `EventLoop` from another thread.
 ///
 /// [`Window`]: crate::window::Window
-pub struct EventLoop<T: 'static> {
-    pub(crate) event_loop: platform_impl::EventLoop<T>,
-    pub(crate) _marker: PhantomData<*mut ()>, // Not Send nor Sync
-}
-
-/// Target that associates windows with an [`EventLoop`].
-///
-/// This type exists to allow you to create new windows while Winit executes
-/// your callback.
-pub struct ActiveEventLoop {
-    pub(crate) p: platform_impl::ActiveEventLoop,
+pub struct EventLoop {
+    pub(crate) event_loop: platform_impl::EventLoop,
     pub(crate) _marker: PhantomData<*mut ()>, // Not Send nor Sync
 }
 
@@ -59,25 +51,15 @@ pub struct ActiveEventLoop {
 /// This is used to make specifying options that affect the whole application
 /// easier. But note that constructing multiple event loops is not supported.
 ///
-/// This can be created using [`EventLoop::new`] or [`EventLoop::with_user_event`].
-#[derive(Default)]
-pub struct EventLoopBuilder<T: 'static> {
+/// This can be created using [`EventLoop::builder`].
+#[derive(Default, PartialEq, Eq, Hash)]
+pub struct EventLoopBuilder {
     pub(crate) platform_specific: platform_impl::PlatformSpecificEventLoopAttributes,
-    _p: PhantomData<T>,
 }
 
 static EVENT_LOOP_CREATED: AtomicBool = AtomicBool::new(false);
 
-impl EventLoopBuilder<()> {
-    /// Start building a new event loop.
-    #[inline]
-    #[deprecated = "use `EventLoop::builder` instead"]
-    pub fn new() -> Self {
-        EventLoop::builder()
-    }
-}
-
-impl<T> EventLoopBuilder<T> {
+impl EventLoopBuilder {
     /// Builds a new event loop.
     ///
     /// ***For cross-platform compatibility, the [`EventLoop`] must be created on the main thread,
@@ -103,13 +85,16 @@ impl<T> EventLoopBuilder<T> {
     ///
     /// [`platform`]: crate::platform
     #[cfg_attr(
-        android,
+        android_platform,
         doc = "[`.with_android_app(app)`]: \
                crate::platform::android::EventLoopBuilderExtAndroid::with_android_app"
     )]
-    #[cfg_attr(not(android), doc = "[`.with_android_app(app)`]: #only-available-on-android")]
+    #[cfg_attr(
+        not(android_platform),
+        doc = "[`.with_android_app(app)`]: #only-available-on-android"
+    )]
     #[inline]
-    pub fn build(&mut self) -> Result<EventLoop<T>, EventLoopError> {
+    pub fn build(&mut self) -> Result<EventLoop, EventLoopError> {
         let _span = tracing::debug_span!("winit::EventLoopBuilder::build").entered();
 
         if EVENT_LOOP_CREATED.swap(true, Ordering::Relaxed) {
@@ -130,26 +115,27 @@ impl<T> EventLoopBuilder<T> {
     }
 }
 
-impl<T> fmt::Debug for EventLoop<T> {
+impl fmt::Debug for EventLoopBuilder {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        f.pad("EventLoop { .. }")
+        f.debug_struct("EventLoopBuilder").finish_non_exhaustive()
     }
 }
 
-impl fmt::Debug for ActiveEventLoop {
+impl fmt::Debug for EventLoop {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        f.pad("ActiveEventLoop { .. }")
+        f.debug_struct("EventLoop").finish_non_exhaustive()
     }
 }
 
 /// Set through [`ActiveEventLoop::set_control_flow()`].
 ///
-/// Indicates the desired behavior of the event loop after [`Event::AboutToWait`] is emitted.
+/// Indicates the desired behavior of the event loop after [`about_to_wait`] is called.
 ///
 /// Defaults to [`Wait`].
 ///
 /// [`Wait`]: Self::Wait
-#[derive(Copy, Clone, Debug, Default, PartialEq, Eq)]
+/// [`about_to_wait`]: crate::application::ApplicationHandler::about_to_wait
+#[derive(Copy, Clone, Debug, Default, PartialEq, Eq, Hash)]
 pub enum ControlFlow {
     /// When the current loop iteration finishes, immediately begin a new iteration regardless of
     /// whether or not new events are available to process.
@@ -186,12 +172,12 @@ impl ControlFlow {
     }
 }
 
-impl EventLoop<()> {
+impl EventLoop {
     /// Create the event loop.
     ///
     /// This is an alias of `EventLoop::builder().build()`.
     #[inline]
-    pub fn new() -> Result<EventLoop<()>, EventLoopError> {
+    pub fn new() -> Result<EventLoop, EventLoopError> {
         Self::builder().build()
     }
 
@@ -201,33 +187,12 @@ impl EventLoop<()> {
     ///
     /// To get the actual event loop, call [`build`][EventLoopBuilder::build] on that.
     #[inline]
-    pub fn builder() -> EventLoopBuilder<()> {
-        Self::with_user_event()
+    pub fn builder() -> EventLoopBuilder {
+        EventLoopBuilder { platform_specific: Default::default() }
     }
 }
 
-impl<T> EventLoop<T> {
-    /// Start building a new event loop, with the given type as the user event
-    /// type.
-    pub fn with_user_event() -> EventLoopBuilder<T> {
-        EventLoopBuilder { platform_specific: Default::default(), _p: PhantomData }
-    }
-
-    /// See [`run_app`].
-    ///
-    /// [`run_app`]: Self::run_app
-    #[inline]
-    #[deprecated = "use `EventLoop::run_app` instead"]
-    #[cfg(not(all(web_platform, target_feature = "exception-handling")))]
-    pub fn run<F>(self, event_handler: F) -> Result<(), EventLoopError>
-    where
-        F: FnMut(Event<T>, &ActiveEventLoop),
-    {
-        let _span = tracing::debug_span!("winit::EventLoop::run").entered();
-
-        self.event_loop.run(event_handler)
-    }
-
+impl EventLoop {
     /// Run the application with the event loop on the calling thread.
     ///
     /// See the [`set_control_flow()`] docs on how to change the event loop's behavior.
@@ -242,37 +207,38 @@ impl<T> EventLoop<T> {
     ///
     ///   Web applications are recommended to use
     #[cfg_attr(
-        web_platform,
-        doc = "[`EventLoopExtWebSys::spawn_app()`][crate::platform::web::EventLoopExtWebSys::spawn_app()]"
+        any(web_platform, docsrs),
+        doc = "  [`EventLoopExtWeb::spawn_app()`][crate::platform::web::EventLoopExtWeb::spawn_app()]"
     )]
-    #[cfg_attr(not(web_platform), doc = "`EventLoopExtWebSys::spawn()`")]
-    ///   [^1] instead of [`run_app()`] to avoid the need
-    ///   for the Javascript exception trick, and to make it clearer that the event loop runs
-    ///   asynchronously (via the browser's own, internal, event loop) and doesn't block the
-    ///   current thread of execution like it does on other platforms.
+    #[cfg_attr(not(any(web_platform, docsrs)), doc = "  `EventLoopExtWeb::spawn_app()`")]
+    ///   [^1] instead of [`run_app()`] to avoid the need for the Javascript exception trick, and to
+    ///   make   it clearer that the event loop runs asynchronously (via the browser's own,
+    ///   internal, event   loop) and doesn't block the current thread of execution like it does
+    ///   on other platforms.
     ///
     ///   This function won't be available with `target_feature = "exception-handling"`.
     ///
+    /// [^1]: `spawn_app()` is only available on the Web platform.
+    ///
     /// [`set_control_flow()`]: ActiveEventLoop::set_control_flow()
     /// [`run_app()`]: Self::run_app()
-    /// [^1]: `EventLoopExtWebSys::spawn_app()` is only available on Web.
     #[inline]
     #[cfg(not(all(web_platform, target_feature = "exception-handling")))]
-    pub fn run_app<A: ApplicationHandler<T>>(self, app: &mut A) -> Result<(), EventLoopError> {
-        self.event_loop.run(|event, event_loop| dispatch_event_for_app(app, event_loop, event))
+    pub fn run_app<A: ApplicationHandler>(self, app: A) -> Result<(), EventLoopError> {
+        self.event_loop.run_app(app)
     }
 
     /// Creates an [`EventLoopProxy`] that can be used to dispatch user events
     /// to the main event loop, possibly from another thread.
-    pub fn create_proxy(&self) -> EventLoopProxy<T> {
-        EventLoopProxy { event_loop_proxy: self.event_loop.create_proxy() }
+    pub fn create_proxy(&self) -> EventLoopProxy {
+        self.event_loop.window_target().create_proxy()
     }
 
     /// Gets a persistent reference to the underlying platform display.
     ///
     /// See the [`OwnedDisplayHandle`] type for more information.
     pub fn owned_display_handle(&self) -> OwnedDisplayHandle {
-        OwnedDisplayHandle { platform: self.event_loop.window_target().p.owned_display_handle() }
+        self.event_loop.window_target().owned_display_handle()
     }
 
     /// Change if or when [`DeviceEvent`]s are captured.
@@ -286,56 +252,36 @@ impl<T> EventLoop<T> {
             allowed = ?allowed
         )
         .entered();
-
-        self.event_loop.window_target().p.listen_device_events(allowed);
+        self.event_loop.window_target().listen_device_events(allowed)
     }
 
     /// Sets the [`ControlFlow`].
     pub fn set_control_flow(&self, control_flow: ControlFlow) {
-        self.event_loop.window_target().p.set_control_flow(control_flow)
-    }
-
-    /// Create a window.
-    ///
-    /// Creating window without event loop running often leads to improper window creation;
-    /// use [`ActiveEventLoop::create_window`] instead.
-    #[deprecated = "use `ActiveEventLoop::create_window` instead"]
-    #[inline]
-    pub fn create_window(&self, window_attributes: WindowAttributes) -> Result<Window, OsError> {
-        let _span = tracing::debug_span!(
-            "winit::EventLoop::create_window",
-            window_attributes = ?window_attributes
-        )
-        .entered();
-
-        let window =
-            platform_impl::Window::new(&self.event_loop.window_target().p, window_attributes)?;
-        Ok(Window { window })
+        self.event_loop.window_target().set_control_flow(control_flow);
     }
 
     /// Create custom cursor.
-    pub fn create_custom_cursor(&self, custom_cursor: CustomCursorSource) -> CustomCursor {
-        self.event_loop.window_target().p.create_custom_cursor(custom_cursor)
+    ///
+    /// ## Platform-specific
+    ///
+    /// **iOS / Android / Orbital:** Unsupported.
+    pub fn create_custom_cursor(
+        &self,
+        custom_cursor: CustomCursorSource,
+    ) -> Result<CustomCursor, ExternalError> {
+        self.event_loop.window_target().create_custom_cursor(custom_cursor)
     }
 }
 
 #[cfg(feature = "rwh_06")]
-impl<T> rwh_06::HasDisplayHandle for EventLoop<T> {
+impl rwh_06::HasDisplayHandle for EventLoop {
     fn display_handle(&self) -> Result<rwh_06::DisplayHandle<'_>, rwh_06::HandleError> {
-        rwh_06::HasDisplayHandle::display_handle(self.event_loop.window_target())
-    }
-}
-
-#[cfg(feature = "rwh_05")]
-unsafe impl<T> rwh_05::HasRawDisplayHandle for EventLoop<T> {
-    /// Returns a [`rwh_05::RawDisplayHandle`] for the event loop.
-    fn raw_display_handle(&self) -> rwh_05::RawDisplayHandle {
-        rwh_05::HasRawDisplayHandle::raw_display_handle(self.event_loop.window_target())
+        rwh_06::HasDisplayHandle::display_handle(self.event_loop.window_target().rwh_06_handle())
     }
 }
 
 #[cfg(any(x11_platform, wayland_platform))]
-impl<T> AsFd for EventLoop<T> {
+impl AsFd for EventLoop {
     /// Get the underlying [EventLoop]'s `fd` which you can register
     /// into other event loop, like [`calloop`] or [`mio`]. When doing so, the
     /// loop must be polled with the [`pump_app_events`] API.
@@ -349,7 +295,7 @@ impl<T> AsFd for EventLoop<T> {
 }
 
 #[cfg(any(x11_platform, wayland_platform))]
-impl<T> AsRawFd for EventLoop<T> {
+impl AsRawFd for EventLoop {
     /// Get the underlying [EventLoop]'s raw `fd` which you can register
     /// into other event loop, like [`calloop`] or [`mio`]. When doing so, the
     /// loop must be polled with the [`pump_app_events`] API.
@@ -362,42 +308,42 @@ impl<T> AsRawFd for EventLoop<T> {
     }
 }
 
-impl ActiveEventLoop {
+pub trait ActiveEventLoop {
+    /// Creates an [`EventLoopProxy`] that can be used to dispatch user events
+    /// to the main event loop, possibly from another thread.
+    fn create_proxy(&self) -> EventLoopProxy;
+
     /// Create the window.
     ///
     /// Possible causes of error include denied permission, incompatible system, and lack of memory.
     ///
     /// ## Platform-specific
     ///
-    /// - **Web:** The window is created but not inserted into the web page automatically. Please
-    ///   see the web platform module for more information.
-    #[inline]
-    pub fn create_window(&self, window_attributes: WindowAttributes) -> Result<Window, OsError> {
-        let _span = tracing::debug_span!(
-            "winit::ActiveEventLoop::create_window",
-            window_attributes = ?window_attributes
-        )
-        .entered();
-
-        let window = platform_impl::Window::new(&self.p, window_attributes)?;
-        Ok(Window { window })
-    }
+    /// - **Web:** The window is created but not inserted into the Web page automatically. Please
+    ///   see the Web platform module for more information.
+    fn create_window(&self, window_attributes: WindowAttributes) -> Result<Window, OsError>;
 
     /// Create custom cursor.
-    pub fn create_custom_cursor(&self, custom_cursor: CustomCursorSource) -> CustomCursor {
-        let _span = tracing::debug_span!("winit::ActiveEventLoop::create_custom_cursor",).entered();
-
-        self.p.create_custom_cursor(custom_cursor)
-    }
+    ///
+    /// ## Platform-specific
+    ///
+    /// **iOS / Android / Orbital:** Unsupported.
+    fn create_custom_cursor(
+        &self,
+        custom_cursor: CustomCursorSource,
+    ) -> Result<CustomCursor, ExternalError>;
 
     /// Returns the list of all the monitors available on the system.
-    #[inline]
-    pub fn available_monitors(&self) -> impl Iterator<Item = MonitorHandle> {
-        let _span = tracing::debug_span!("winit::ActiveEventLoop::available_monitors",).entered();
-
-        #[allow(clippy::useless_conversion)] // false positive on some platforms
-        self.p.available_monitors().into_iter().map(|inner| MonitorHandle { inner })
-    }
+    ///
+    /// ## Platform-specific
+    ///
+    /// **Web:** Only returns the current monitor without
+    #[cfg_attr(
+        any(web_platform, docsrs),
+        doc = "[detailed monitor permissions][crate::platform::web::ActiveEventLoopExtWeb::request_detailed_monitor_permission]."
+    )]
+    #[cfg_attr(not(any(web_platform, docsrs)), doc = "detailed monitor permissions.")]
+    fn available_monitors(&self) -> Box<dyn Iterator<Item = MonitorHandle>>;
 
     /// Returns the primary monitor of the system.
     ///
@@ -405,13 +351,14 @@ impl ActiveEventLoop {
     ///
     /// ## Platform-specific
     ///
-    /// **Wayland / Web:** Always returns `None`.
-    #[inline]
-    pub fn primary_monitor(&self) -> Option<MonitorHandle> {
-        let _span = tracing::debug_span!("winit::ActiveEventLoop::primary_monitor",).entered();
-
-        self.p.primary_monitor().map(|inner| MonitorHandle { inner })
-    }
+    /// - **Wayland:** Always returns `None`.
+    /// - **Web:** Always returns `None` without
+    #[cfg_attr(
+        any(web_platform, docsrs),
+        doc = "  [detailed monitor permissions][crate::platform::web::ActiveEventLoopExtWeb::request_detailed_monitor_permission]."
+    )]
+    #[cfg_attr(not(any(web_platform, docsrs)), doc = "  detailed monitor permissions.")]
+    fn primary_monitor(&self) -> Option<MonitorHandle>;
 
     /// Change if or when [`DeviceEvent`]s are captured.
     ///
@@ -424,65 +371,46 @@ impl ActiveEventLoop {
     /// - **Wayland / macOS / iOS / Android / Orbital:** Unsupported.
     ///
     /// [`DeviceEvent`]: crate::event::DeviceEvent
-    pub fn listen_device_events(&self, allowed: DeviceEvents) {
-        let _span = tracing::debug_span!(
-            "winit::ActiveEventLoop::listen_device_events",
-            allowed = ?allowed
-        )
-        .entered();
+    fn listen_device_events(&self, allowed: DeviceEvents);
 
-        self.p.listen_device_events(allowed);
-    }
+    /// Returns the current system theme.
+    ///
+    /// Returns `None` if it cannot be determined on the current platform.
+    ///
+    /// ## Platform-specific
+    ///
+    /// - **iOS / Android / Wayland / x11 / Orbital:** Unsupported.
+    fn system_theme(&self) -> Option<Theme>;
 
     /// Sets the [`ControlFlow`].
-    pub fn set_control_flow(&self, control_flow: ControlFlow) {
-        self.p.set_control_flow(control_flow)
-    }
+    fn set_control_flow(&self, control_flow: ControlFlow);
 
     /// Gets the current [`ControlFlow`].
-    pub fn control_flow(&self) -> ControlFlow {
-        self.p.control_flow()
-    }
+    fn control_flow(&self) -> ControlFlow;
 
     /// This exits the event loop.
     ///
-    /// See [`LoopExiting`][Event::LoopExiting].
-    pub fn exit(&self) {
-        let _span = tracing::debug_span!("winit::ActiveEventLoop::exit",).entered();
-
-        self.p.exit()
-    }
+    /// See [`exiting`][crate::application::ApplicationHandler::exiting].
+    fn exit(&self);
 
     /// Returns if the [`EventLoop`] is about to stop.
     ///
     /// See [`exit()`][Self::exit].
-    pub fn exiting(&self) -> bool {
-        self.p.exiting()
-    }
+    fn exiting(&self) -> bool;
 
     /// Gets a persistent reference to the underlying platform display.
     ///
     /// See the [`OwnedDisplayHandle`] type for more information.
-    pub fn owned_display_handle(&self) -> OwnedDisplayHandle {
-        OwnedDisplayHandle { platform: self.p.owned_display_handle() }
-    }
-}
+    fn owned_display_handle(&self) -> OwnedDisplayHandle;
 
-#[cfg(feature = "rwh_06")]
-impl rwh_06::HasDisplayHandle for ActiveEventLoop {
-    fn display_handle(&self) -> Result<rwh_06::DisplayHandle<'_>, rwh_06::HandleError> {
-        let raw = self.p.raw_display_handle_rwh_06()?;
-        // SAFETY: The display will never be deallocated while the event loop is alive.
-        Ok(unsafe { rwh_06::DisplayHandle::borrow_raw(raw) })
-    }
-}
+    /// Get the [`ActiveEventLoop`] as [`Any`].
+    ///
+    /// This is useful for downcasting to a concrete event loop type.
+    fn as_any(&self) -> &dyn Any;
 
-#[cfg(feature = "rwh_05")]
-unsafe impl rwh_05::HasRawDisplayHandle for ActiveEventLoop {
-    /// Returns a [`rwh_05::RawDisplayHandle`] for the event loop.
-    fn raw_display_handle(&self) -> rwh_05::RawDisplayHandle {
-        self.p.raw_display_handle_rwh_05()
-    }
+    /// Get the raw-window-handle handle.
+    #[cfg(feature = "rwh_06")]
+    fn rwh_06_handle(&self) -> &dyn rwh_06::HasDisplayHandle;
 }
 
 /// A proxy for the underlying display handle.
@@ -497,10 +425,10 @@ unsafe impl rwh_05::HasRawDisplayHandle for ActiveEventLoop {
 ///
 /// - A zero-sized type that is likely optimized out.
 /// - A reference-counted pointer to the underlying type.
-#[derive(Clone)]
+#[derive(Clone, PartialEq, Eq)]
 pub struct OwnedDisplayHandle {
-    #[cfg_attr(not(any(feature = "rwh_05", feature = "rwh_06")), allow(dead_code))]
-    platform: platform_impl::OwnedDisplayHandle,
+    #[cfg_attr(not(feature = "rwh_06"), allow(dead_code))]
+    pub(crate) platform: platform_impl::OwnedDisplayHandle,
 }
 
 impl fmt::Debug for OwnedDisplayHandle {
@@ -523,63 +451,42 @@ impl rwh_06::HasDisplayHandle for OwnedDisplayHandle {
     }
 }
 
-#[cfg(feature = "rwh_05")]
-unsafe impl rwh_05::HasRawDisplayHandle for OwnedDisplayHandle {
-    #[inline]
-    fn raw_display_handle(&self) -> rwh_05::RawDisplayHandle {
-        self.platform.raw_display_handle_rwh_05()
-    }
+/// Control the [`EventLoop`], possibly from a different thread, without referencing it directly.
+#[derive(Clone)]
+pub struct EventLoopProxy {
+    pub(crate) event_loop_proxy: platform_impl::EventLoopProxy,
 }
 
-/// Used to send custom events to [`EventLoop`].
-pub struct EventLoopProxy<T: 'static> {
-    event_loop_proxy: platform_impl::EventLoopProxy<T>,
-}
-
-impl<T: 'static> Clone for EventLoopProxy<T> {
-    fn clone(&self) -> Self {
-        Self { event_loop_proxy: self.event_loop_proxy.clone() }
-    }
-}
-
-impl<T: 'static> EventLoopProxy<T> {
-    /// Send an event to the [`EventLoop`] from which this proxy was created. This emits a
-    /// `UserEvent(event)` event in the event loop, where `event` is the value passed to this
-    /// function.
+impl EventLoopProxy {
+    /// Wake up the [`EventLoop`], resulting in [`ApplicationHandler::proxy_wake_up()`] being
+    /// called.
     ///
-    /// Returns an `Err` if the associated [`EventLoop`] no longer exists.
+    /// Calls to this method are coalesced into a single call to [`proxy_wake_up`], see the
+    /// documentation on that for details.
     ///
-    /// [`UserEvent(event)`]: Event::UserEvent
-    pub fn send_event(&self, event: T) -> Result<(), EventLoopClosed<T>> {
-        let _span = tracing::debug_span!("winit::EventLoopProxy::send_event",).entered();
-
-        self.event_loop_proxy.send_event(event)
+    /// If the event loop is no longer running, this is a no-op.
+    ///
+    /// [`proxy_wake_up`]: ApplicationHandler::proxy_wake_up
+    ///
+    /// # Platform-specific
+    ///
+    /// - **Windows**: The wake-up may be ignored under high contention, see [#3687].
+    ///
+    /// [#3687]: https://github.com/rust-windowing/winit/pull/3687
+    pub fn wake_up(&self) {
+        self.event_loop_proxy.wake_up();
     }
 }
 
-impl<T: 'static> fmt::Debug for EventLoopProxy<T> {
+impl fmt::Debug for EventLoopProxy {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        f.pad("EventLoopProxy { .. }")
+        f.debug_struct("ActiveEventLoop").finish_non_exhaustive()
     }
 }
 
-/// The error that is returned when an [`EventLoopProxy`] attempts to wake up an [`EventLoop`] that
-/// no longer exists.
-///
-/// Contains the original event given to [`EventLoopProxy::send_event`].
-#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
-pub struct EventLoopClosed<T>(pub T);
-
-impl<T> fmt::Display for EventLoopClosed<T> {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        f.write_str("Tried to wake up a closed `EventLoop`")
-    }
-}
-
-impl<T: fmt::Debug> error::Error for EventLoopClosed<T> {}
-
 /// Control when device events are captured.
 #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Debug, Default)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 pub enum DeviceEvents {
     /// Report device events regardless of window focus.
     Always,
@@ -599,7 +506,7 @@ pub enum DeviceEvents {
 /// containing [`AsyncRequestSerial`] and some closure associated with it.
 /// Then once event is arriving the working list is being traversed and a job
 /// executed and removed from the list.
-#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
 pub struct AsyncRequestSerial {
     serial: usize,
 }
@@ -615,23 +522,3 @@ impl AsyncRequestSerial {
         Self { serial }
     }
 }
-
-/// Shim for various run APIs.
-#[inline(always)]
-pub(crate) fn dispatch_event_for_app<T: 'static, A: ApplicationHandler<T>>(
-    app: &mut A,
-    event_loop: &ActiveEventLoop,
-    event: Event<T>,
-) {
-    match event {
-        Event::NewEvents(cause) => app.new_events(event_loop, cause),
-        Event::WindowEvent { window_id, event } => app.window_event(event_loop, window_id, event),
-        Event::DeviceEvent { device_id, event } => app.device_event(event_loop, device_id, event),
-        Event::UserEvent(event) => app.user_event(event_loop, event),
-        Event::Suspended => app.suspended(event_loop),
-        Event::Resumed => app.resumed(event_loop),
-        Event::AboutToWait => app.about_to_wait(event_loop),
-        Event::LoopExiting => app.exiting(event_loop),
-        Event::MemoryWarning => app.memory_warning(event_loop),
-    }
-}

src/icon.rs

@@ -1,7 +1,8 @@
-use crate::platform_impl::PlatformIcon;
 use std::error::Error;
 use std::{fmt, io, mem};
 
+use crate::platform_impl::PlatformIcon;
+
 #[repr(C)]
 #[derive(Debug)]
 pub(crate) struct Pixel {
@@ -49,15 +50,15 @@ impl fmt::Display for BadIcon {
 
 impl Error for BadIcon {}
 
-#[derive(Debug, Clone, PartialEq, Eq)]
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub(crate) struct RgbaIcon {
     pub(crate) rgba: Vec<u8>,
     pub(crate) width: u32,
     pub(crate) height: u32,
 }
 
-/// For platforms which don't have window icons (e.g. web)
-#[derive(Debug, Clone, PartialEq, Eq)]
+/// For platforms which don't have window icons (e.g. Web)
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub(crate) struct NoIcon;
 
 #[allow(dead_code)] // These are not used on every platform
@@ -93,7 +94,7 @@ mod constructors {
 }
 
 /// An icon used for the window titlebar, taskbar, etc.
-#[derive(Clone)]
+#[derive(Clone, Eq, Hash, PartialEq)]
 pub struct Icon {
     pub(crate) inner: PlatformIcon,
 }

src/keyboard.rs

@@ -84,7 +84,7 @@ pub use smol_str::SmolStr;
 /// haven't mapped for you yet, this lets you use use [`KeyCode`] to:
 ///
 /// - Correctly match key press and release events.
-/// - On non-web platforms, support assigning keybinds to virtually any key through a UI.
+/// - On non-Web platforms, support assigning keybinds to virtually any key through a UI.
 #[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 pub enum NativeKeyCode {
@@ -1568,10 +1568,15 @@ impl NamedKey {
     /// # Examples
     ///
     /// ```
+    /// # #[cfg(web_platform)]
+    /// # wasm_bindgen_test::wasm_bindgen_test_configure!(run_in_browser);
+    /// # #[cfg_attr(web_platform, wasm_bindgen_test::wasm_bindgen_test)]
+    /// # fn main() {
     /// use winit::keyboard::NamedKey;
     ///
     /// assert_eq!(NamedKey::Enter.to_text(), Some("\r"));
     /// assert_eq!(NamedKey::F20.to_text(), None);
+    /// # }
     /// ```
     pub fn to_text(&self) -> Option<&str> {
         match self {
@@ -1591,11 +1596,16 @@ impl Key {
     /// # Examples
     ///
     /// ```
+    /// # #[cfg(web_platform)]
+    /// # wasm_bindgen_test::wasm_bindgen_test_configure!(run_in_browser);
+    /// # #[cfg_attr(web_platform, wasm_bindgen_test::wasm_bindgen_test)]
+    /// # fn main() {
     /// use winit::keyboard::{Key, NamedKey};
     ///
     /// assert_eq!(Key::Character("a".into()).to_text(), Some("a"));
     /// assert_eq!(Key::Named(NamedKey::Enter).to_text(), Some("\r"));
     /// assert_eq!(Key::Named(NamedKey::F20).to_text(), None);
+    /// # }
     /// ```
     pub fn to_text(&self) -> Option<&str> {
         match self {
@@ -1618,7 +1628,7 @@ impl Key {
 ///
 /// [`location`]: ../event/struct.KeyEvent.html#structfield.location
 /// [`KeyEvent`]: crate::event::KeyEvent
-#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, PartialOrd, Ord)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 pub enum KeyLocation {
     /// The key is in its "normal" location on the keyboard.
@@ -1690,6 +1700,7 @@ bitflags! {
     ///
     /// Each flag represents a modifier and is set if this modifier is active.
     #[derive(Default, Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
+    #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
     pub struct ModifiersState: u32 {
         /// The "shift" key.
         const SHIFT = 0b100;
@@ -1725,7 +1736,8 @@ impl ModifiersState {
 }
 
 /// The state of the particular modifiers key.
-#[derive(Default, Debug, Clone, Copy, PartialEq, Eq)]
+#[derive(Default, Debug, Clone, Copy, PartialEq, Eq, Hash, PartialOrd, Ord)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 pub enum ModifiersKeyState {
     /// The particular key is pressed.
     Pressed,
@@ -1744,6 +1756,7 @@ pub enum ModifiersKeyState {
 // on macOS due to their AltGr/Option situation.
 bitflags! {
     #[derive(Default, Debug, Clone, Copy, PartialEq, Eq, Hash)]
+    #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
     pub(crate) struct ModifiersKeys: u8 {
         const LSHIFT   = 0b0000_0001;
         const RSHIFT   = 0b0000_0010;
@@ -1755,50 +1768,3 @@ bitflags! {
         const RSUPER   = 0b1000_0000;
     }
 }
-
-#[cfg(feature = "serde")]
-mod modifiers_serde {
-    use super::ModifiersState;
-    use serde::{Deserialize, Deserializer, Serialize, Serializer};
-
-    #[derive(Default, Serialize, Deserialize)]
-    #[serde(default)]
-    #[serde(rename = "ModifiersState")]
-    pub struct ModifiersStateSerialize {
-        pub shift_key: bool,
-        pub control_key: bool,
-        pub alt_key: bool,
-        pub super_key: bool,
-    }
-
-    impl Serialize for ModifiersState {
-        fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
-        where
-            S: Serializer,
-        {
-            let s = ModifiersStateSerialize {
-                shift_key: self.shift_key(),
-                control_key: self.control_key(),
-                alt_key: self.alt_key(),
-                super_key: self.super_key(),
-            };
-            s.serialize(serializer)
-        }
-    }
-
-    impl<'de> Deserialize<'de> for ModifiersState {
-        fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
-        where
-            D: Deserializer<'de>,
-        {
-            let ModifiersStateSerialize { shift_key, control_key, alt_key, super_key } =
-                ModifiersStateSerialize::deserialize(deserializer)?;
-            let mut m = ModifiersState::empty();
-            m.set(ModifiersState::SHIFT, shift_key);
-            m.set(ModifiersState::CONTROL, control_key);
-            m.set(ModifiersState::ALT, alt_key);
-            m.set(ModifiersState::SUPER, super_key);
-            Ok(m)
-        }
-    }
-}

src/lib.rs

@@ -19,15 +19,14 @@
 //! window or a key getting pressed while the window is focused. Devices can generate
 //! [`DeviceEvent`]s, which contain unfiltered event data that isn't specific to a certain window.
 //! Some user activity, like mouse movement, can generate both a [`WindowEvent`] *and* a
-//! [`DeviceEvent`]. You can also create and handle your own custom [`Event::UserEvent`]s, if
-//! desired.
+//! [`DeviceEvent`].
 //!
 //! You can retrieve events by calling [`EventLoop::run_app()`]. This function will
 //! dispatch events for every [`Window`] that was created with that particular [`EventLoop`], and
-//! will run until [`exit()`] is used, at which point [`Event::LoopExiting`].
+//! will run until [`exit()`] is used, at which point [`exiting()`] is called.
 //!
 //! Winit no longer uses a `EventLoop::poll_events() -> impl Iterator<Event>`-based event loop
-//! model, since that can't be implemented properly on some platforms (e.g web, iOS) and works
+//! model, since that can't be implemented properly on some platforms (e.g Web, iOS) and works
 //! poorly on most other platforms. However, this model can be re-implemented to an extent with
 #![cfg_attr(
     any(windows_platform, macos_platform, android_platform, x11_platform, wayland_platform),
@@ -53,11 +52,11 @@
 //! }
 //!
 //! impl ApplicationHandler for App {
-//!     fn resumed(&mut self, event_loop: &ActiveEventLoop) {
+//!     fn can_create_surfaces(&mut self, event_loop: &dyn ActiveEventLoop) {
 //!         self.window = Some(event_loop.create_window(Window::default_attributes()).unwrap());
 //!     }
 //!
-//!     fn window_event(&mut self, event_loop: &ActiveEventLoop, id: WindowId, event: WindowEvent) {
+//!     fn window_event(&mut self, event_loop: &dyn ActiveEventLoop, id: WindowId, event: WindowEvent) {
 //!         match event {
 //!             WindowEvent::CloseRequested => {
 //!                 println!("The close button was pressed; stopping");
@@ -141,8 +140,6 @@
 //!
 //! * `x11` (enabled by default): On Unix platforms, enables the X11 backend.
 //! * `wayland` (enabled by default): On Unix platforms, enables the Wayland backend.
-//! * `rwh_04`: Implement `raw-window-handle v0.4` traits.
-//! * `rwh_05`: Implement `raw-window-handle v0.5` traits.
 //! * `rwh_06`: Implement `raw-window-handle v0.6` traits.
 //! * `serde`: Enables serialization/deserialization of certain types with [Serde](https://crates.io/crates/serde).
 //! * `mint`: Enables mint (math interoperability standard types) conversions.
@@ -163,7 +160,7 @@
 //! [`WindowEvent`]: event::WindowEvent
 //! [`DeviceEvent`]: event::DeviceEvent
 //! [`Event::UserEvent`]: event::Event::UserEvent
-//! [`Event::LoopExiting`]: event::Event::LoopExiting
+//! [`exiting()`]: crate::application::ApplicationHandler::exiting
 //! [`raw_window_handle`]: ./window/struct.Window.html#method.raw_window_handle
 //! [`raw_display_handle`]: ./window/struct.Window.html#method.raw_display_handle
 //! [^1]: `EventLoopExtPumpEvents::pump_app_events()` is only available on Windows, macOS, Android, X11 and Wayland.
@@ -178,12 +175,11 @@
 #![cfg_attr(docsrs, feature(doc_auto_cfg, doc_cfg_hide), doc(cfg_hide(doc, docsrs)))]
 #![allow(clippy::missing_safety_doc)]
 
-#[cfg(feature = "rwh_06")]
-pub use rwh_06 as raw_window_handle;
-
 // Re-export DPI types so that users don't have to put it in Cargo.toml.
 #[doc(inline)]
 pub use dpi;
+#[cfg(feature = "rwh_06")]
+pub use rwh_06 as raw_window_handle;
 
 pub mod application;
 #[cfg(any(doc, doctest, test))]

src/monitor.rs

@@ -5,13 +5,11 @@
 //! methods, which return an iterator of [`MonitorHandle`]:
 //! - [`ActiveEventLoop::available_monitors`][crate::event_loop::ActiveEventLoop::available_monitors].
 //! - [`Window::available_monitors`][crate::window::Window::available_monitors].
+use std::num::{NonZeroU16, NonZeroU32};
+
 use crate::dpi::{PhysicalPosition, PhysicalSize};
 use crate::platform_impl;
 
-/// Deprecated! Use `VideoModeHandle` instead.
-#[deprecated = "Renamed to `VideoModeHandle`"]
-pub type VideoMode = VideoModeHandle;
-
 /// Describes a fullscreen video mode of a monitor.
 ///
 /// Can be acquired with [`MonitorHandle::video_modes`].
@@ -48,7 +46,10 @@ impl Ord for VideoModeHandle {
 }
 
 impl VideoModeHandle {
-    /// Returns the resolution of this video mode.
+    /// Returns the resolution of this video mode. This **must not** be used to create your
+    /// rendering surface. Use [`Window::inner_size()`] instead.
+    ///
+    /// [`Window::inner_size()`]: crate::window::Window::inner_size
     #[inline]
     pub fn size(&self) -> PhysicalSize<u32> {
         self.video_mode.size()
@@ -57,19 +58,14 @@ impl VideoModeHandle {
     /// Returns the bit depth of this video mode, as in how many bits you have
     /// available per color. This is generally 24 bits or 32 bits on modern
     /// systems, depending on whether the alpha channel is counted or not.
-    ///
-    /// ## Platform-specific
-    ///
-    /// - **Wayland / Orbital:** Always returns 32.
-    /// - **iOS:** Always returns 32.
     #[inline]
-    pub fn bit_depth(&self) -> u16 {
+    pub fn bit_depth(&self) -> Option<NonZeroU16> {
         self.video_mode.bit_depth()
     }
 
     /// Returns the refresh rate of this video mode in mHz.
     #[inline]
-    pub fn refresh_rate_millihertz(&self) -> u32 {
+    pub fn refresh_rate_millihertz(&self) -> Option<NonZeroU32> {
         self.video_mode.refresh_rate_millihertz()
     }
 
@@ -85,11 +81,11 @@ impl std::fmt::Display for VideoModeHandle {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         write!(
             f,
-            "{}x{} @ {} mHz ({} bpp)",
+            "{}x{} {}{}",
             self.size().width,
             self.size().height,
-            self.refresh_rate_millihertz(),
-            self.bit_depth()
+            self.refresh_rate_millihertz().map(|rate| format!("@ {rate} mHz ")).unwrap_or_default(),
+            self.bit_depth().map(|bit_depth| format!("({bit_depth} bpp)")).unwrap_or_default(),
         )
     }
 }
@@ -98,46 +94,69 @@ impl std::fmt::Display for VideoModeHandle {
 ///
 /// Allows you to retrieve information about a given monitor and can be used in [`Window`] creation.
 ///
+/// ## Platform-specific
+///
+/// **Web:** A [`MonitorHandle`] created without
+#[cfg_attr(
+    any(web_platform, docsrs),
+    doc = "[detailed monitor permissions][crate::platform::web::ActiveEventLoopExtWeb::request_detailed_monitor_permission]."
+)]
+#[cfg_attr(not(any(web_platform, docsrs)), doc = "detailed monitor permissions.")]
+/// will always represent the current monitor the browser window is in instead of a specific
+/// monitor. See
+#[cfg_attr(
+    any(web_platform, docsrs),
+    doc = "[`MonitorHandleExtWeb::is_detailed()`][crate::platform::web::MonitorHandleExtWeb::is_detailed]"
+)]
+#[cfg_attr(not(any(web_platform, docsrs)), doc = "`MonitorHandleExtWeb::is_detailed()`")]
+/// to check.
+///
 /// [`Window`]: crate::window::Window
-#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord)]
+#[derive(Clone, PartialEq, Eq, Hash, PartialOrd, Ord)]
 pub struct MonitorHandle {
     pub(crate) inner: platform_impl::MonitorHandle,
 }
 
+impl std::fmt::Debug for MonitorHandle {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        self.inner.fmt(f)
+    }
+}
+
 impl MonitorHandle {
     /// Returns a human-readable name of the monitor.
     ///
     /// Returns `None` if the monitor doesn't exist anymore.
+    ///
+    /// ## Platform-specific
+    ///
+    /// **Web:** Always returns [`None`] without
+    #[cfg_attr(
+        any(web_platform, docsrs),
+        doc = "[detailed monitor permissions][crate::platform::web::ActiveEventLoopExtWeb::request_detailed_monitor_permission]."
+    )]
+    #[cfg_attr(not(any(web_platform, docsrs)), doc = "detailed monitor permissions.")]
     #[inline]
     pub fn name(&self) -> Option<String> {
         self.inner.name()
     }
 
-    /// Returns the monitor's resolution.
-    #[inline]
-    pub fn size(&self) -> PhysicalSize<u32> {
-        self.inner.size()
-    }
-
     /// Returns the top-left corner position of the monitor relative to the larger full
     /// screen area.
+    ///
+    /// ## Platform-specific
+    ///
+    /// **Web:** Always returns [`None`] without
+    #[cfg_attr(
+        any(web_platform, docsrs),
+        doc = "[detailed monitor permissions][crate::platform::web::ActiveEventLoopExtWeb::request_detailed_monitor_permission]."
+    )]
+    #[cfg_attr(not(any(web_platform, docsrs)), doc = "detailed monitor permissions.")]
     #[inline]
-    pub fn position(&self) -> PhysicalPosition<i32> {
+    pub fn position(&self) -> Option<PhysicalPosition<i32>> {
         self.inner.position()
     }
 
-    /// The monitor refresh rate used by the system.
-    ///
-    /// Return `Some` if succeed, or `None` if failed, which usually happens when the monitor
-    /// the window is on is removed.
-    ///
-    /// When using exclusive fullscreen, the refresh rate of the [`VideoModeHandle`] that was
-    /// used to enter fullscreen should be used instead.
-    #[inline]
-    pub fn refresh_rate_millihertz(&self) -> Option<u32> {
-        self.inner.refresh_rate_millihertz()
-    }
-
     /// Returns the scale factor of the underlying monitor. To map logical pixels to physical
     /// pixels and vice versa, use [`Window::scale_factor`].
     ///
@@ -148,18 +167,27 @@ impl MonitorHandle {
     /// - **X11:** Can be overridden using the `WINIT_X11_SCALE_FACTOR` environment variable.
     /// - **Wayland:** May differ from [`Window::scale_factor`].
     /// - **Android:** Always returns 1.0.
+    /// - **Web:** Always returns `0.0` without
+    #[cfg_attr(
+        any(web_platform, docsrs),
+        doc = "  [detailed monitor permissions][crate::platform::web::ActiveEventLoopExtWeb::request_detailed_monitor_permission]."
+    )]
+    #[cfg_attr(not(any(web_platform, docsrs)), doc = "  detailed monitor permissions.")]
     ///
+    #[rustfmt::skip]
     /// [`Window::scale_factor`]: crate::window::Window::scale_factor
     #[inline]
     pub fn scale_factor(&self) -> f64 {
         self.inner.scale_factor()
     }
 
+    /// Returns the currently active video mode of this monitor.
+    #[inline]
+    pub fn current_video_mode(&self) -> Option<VideoModeHandle> {
+        self.inner.current_video_mode().map(|video_mode| VideoModeHandle { video_mode })
+    }
+
     /// Returns all fullscreen video modes supported by this monitor.
-    ///
-    /// ## Platform-specific
-    ///
-    /// - **Web:** Always returns an empty iterator
     #[inline]
     pub fn video_modes(&self) -> impl Iterator<Item = VideoModeHandle> {
         self.inner.video_modes().map(|video_mode| VideoModeHandle { video_mode })

src/platform/android.rs

@@ -62,7 +62,7 @@
 //! If your application is currently based on `NativeActivity` via the `ndk-glue` crate and building
 //! with `cargo apk`, then the minimal changes would be:
 //! 1. Remove `ndk-glue` from your `Cargo.toml`
-//! 2. Enable the `"android-native-activity"` feature for Winit: `winit = { version = "0.30.0",
+//! 2. Enable the `"android-native-activity"` feature for Winit: `winit = { version = "0.30.4",
 //!    features = [ "android-native-activity" ] }`
 //! 3. Add an `android_main` entrypoint (as above), instead of using the '`[ndk_glue::main]` proc
 //!    macro from `ndk-macros` (optionally add a dependency on `android_logger` and initialize
@@ -70,18 +70,27 @@
 //! 4. Pass a clone of the `AndroidApp` that your application receives to Winit when building your
 //!    event loop (as shown above).
 
+use self::activity::{AndroidApp, ConfigurationRef, Rect};
 use crate::event_loop::{ActiveEventLoop, EventLoop, EventLoopBuilder};
 use crate::window::{Window, WindowAttributes};
 
-use self::activity::{AndroidApp, ConfigurationRef, Rect};
-
 /// Additional methods on [`EventLoop`] that are specific to Android.
-pub trait EventLoopExtAndroid {}
+pub trait EventLoopExtAndroid {
+    /// Get the [`AndroidApp`] which was used to create this event loop.
+    fn android_app(&self) -> &AndroidApp;
+}
 
-impl<T> EventLoopExtAndroid for EventLoop<T> {}
+impl EventLoopExtAndroid for EventLoop {
+    fn android_app(&self) -> &AndroidApp {
+        &self.event_loop.android_app
+    }
+}
 
 /// Additional methods on [`ActiveEventLoop`] that are specific to Android.
-pub trait ActiveEventLoopExtAndroid {}
+pub trait ActiveEventLoopExtAndroid {
+    /// Get the [`AndroidApp`] which was used to create this event loop.
+    fn android_app(&self) -> &AndroidApp;
+}
 
 /// Additional methods on [`Window`] that are specific to Android.
 pub trait WindowExtAndroid {
@@ -100,7 +109,13 @@ impl WindowExtAndroid for Window {
     }
 }
 
-impl ActiveEventLoopExtAndroid for ActiveEventLoop {}
+impl ActiveEventLoopExtAndroid for &dyn ActiveEventLoop {
+    fn android_app(&self) -> &AndroidApp {
+        let event_loop =
+            self.as_any().downcast_ref::<crate::platform_impl::ActiveEventLoop>().unwrap();
+        &event_loop.app
+    }
+}
 
 /// Additional methods on [`WindowAttributes`] that are specific to Android.
 pub trait WindowAttributesExtAndroid {}
@@ -108,9 +123,9 @@ pub trait WindowAttributesExtAndroid {}
 impl WindowAttributesExtAndroid for WindowAttributes {}
 
 pub trait EventLoopBuilderExtAndroid {
-    /// Associates the `AndroidApp` that was passed to `android_main()` with the event loop
+    /// Associates the [`AndroidApp`] that was passed to `android_main()` with the event loop
     ///
-    /// This must be called on Android since the `AndroidApp` is not global state.
+    /// This must be called on Android since the [`AndroidApp`] is not global state.
     fn with_android_app(&mut self, app: AndroidApp) -> &mut Self;
 
     /// Calling this will mark the volume keys to be manually handled by the application
@@ -119,7 +134,7 @@ pub trait EventLoopBuilderExtAndroid {
     fn handle_volume_keys(&mut self) -> &mut Self;
 }
 
-impl<T> EventLoopBuilderExtAndroid for EventLoopBuilder<T> {
+impl EventLoopBuilderExtAndroid for EventLoopBuilder {
     fn with_android_app(&mut self, app: AndroidApp) -> &mut Self {
         self.platform_specific.android_app = Some(app);
         self
@@ -147,7 +162,7 @@ impl<T> EventLoopBuilderExtAndroid for EventLoopBuilder<T> {
 /// depending on the `android_activity` crate, and instead consume the API that
 /// is re-exported by Winit.
 ///
-/// For compatibility applications should then import the `AndroidApp` type for
+/// For compatibility applications should then import the [`AndroidApp`] type for
 /// their `android_main(app: AndroidApp)` function like:
 /// ```rust
 /// #[cfg(target_os = "android")]

src/platform/ios.rs

@@ -66,22 +66,12 @@
 
 use std::os::raw::c_void;
 
-use crate::event_loop::EventLoop;
+#[cfg(feature = "serde")]
+use serde::{Deserialize, Serialize};
+
 use crate::monitor::{MonitorHandle, VideoModeHandle};
 use crate::window::{Window, WindowAttributes};
 
-/// Additional methods on [`EventLoop`] that are specific to iOS.
-pub trait EventLoopExtIOS {
-    /// Returns the [`Idiom`] (phone/tablet/tv/etc) for the current device.
-    fn idiom(&self) -> Idiom;
-}
-
-impl<T: 'static> EventLoopExtIOS for EventLoop<T> {
-    fn idiom(&self) -> Idiom {
-        self.event_loop.idiom()
-    }
-}
-
 /// Additional methods on [`Window`] that are specific to iOS.
 pub trait WindowExtIOS {
     /// Sets the [`contentScaleFactor`] of the underlying [`UIWindow`] to `scale_factor`.
@@ -357,7 +347,7 @@ impl MonitorHandleExtIOS for MonitorHandle {
     fn ui_screen(&self) -> *mut c_void {
         // SAFETY: The marker is only used to get the pointer of the screen
         let mtm = unsafe { objc2_foundation::MainThreadMarker::new_unchecked() };
-        objc2::rc::Id::as_ptr(self.inner.ui_screen(mtm)) as *mut c_void
+        objc2::rc::Retained::as_ptr(self.inner.ui_screen(mtm)) as *mut c_void
     }
 
     #[inline]
@@ -368,6 +358,7 @@ impl MonitorHandleExtIOS for MonitorHandle {
 
 /// Valid orientations for a particular [`Window`].
 #[derive(Default, Debug, Clone, Copy, PartialEq, Eq, Hash)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 pub enum ValidOrientations {
     /// Excludes `PortraitUpsideDown` on iphone
     #[default]
@@ -379,29 +370,12 @@ pub enum ValidOrientations {
     Portrait,
 }
 
-/// The device [idiom].
-///
-/// [idiom]: https://developer.apple.com/documentation/uikit/uidevice/1620037-userinterfaceidiom?language=objc
-#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
-pub enum Idiom {
-    Unspecified,
-
-    /// iPhone and iPod touch.
-    Phone,
-
-    /// iPad.
-    Pad,
-
-    /// tvOS and Apple TV.
-    TV,
-    CarPlay,
-}
-
 bitflags::bitflags! {
     /// The [edges] of a screen.
     ///
     /// [edges]: https://developer.apple.com/documentation/uikit/uirectedge?language=objc
     #[derive(Default, Debug, Clone, Copy, PartialEq, Eq, Hash)]
+    #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
     pub struct ScreenEdge: u8 {
         const NONE   = 0;
         const TOP    = 1 << 0;
@@ -413,7 +387,8 @@ bitflags::bitflags! {
     }
 }
 
-#[derive(Clone, Copy, Debug, Default, PartialEq, Eq)]
+#[derive(Clone, Copy, Debug, Default, PartialEq, Eq, Hash)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 pub enum StatusBarStyle {
     #[default]
     Default,

src/platform/macos.rs

@@ -170,6 +170,7 @@ impl WindowExtMacOS for Window {
 
 /// Corresponds to `NSApplicationActivationPolicy`.
 #[derive(Debug, Default, Clone, Copy, PartialEq, Eq, Hash)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 pub enum ActivationPolicy {
     /// Corresponds to `NSApplicationActivationPolicyRegular`.
     #[default]
@@ -338,7 +339,7 @@ pub trait EventLoopBuilderExtMacOS {
     fn with_activate_ignoring_other_apps(&mut self, ignore: bool) -> &mut Self;
 }
 
-impl<T> EventLoopBuilderExtMacOS for EventLoopBuilder<T> {
+impl EventLoopBuilderExtMacOS for EventLoopBuilder {
     #[inline]
     fn with_activation_policy(&mut self, activation_policy: ActivationPolicy) -> &mut Self {
         self.platform_specific.activation_policy = activation_policy;
@@ -375,7 +376,7 @@ impl MonitorHandleExtMacOS for MonitorHandle {
     fn ns_screen(&self) -> Option<*mut c_void> {
         // SAFETY: We only use the marker to get a pointer
         let mtm = unsafe { objc2_foundation::MainThreadMarker::new_unchecked() };
-        self.inner.ns_screen(mtm).map(|s| objc2::rc::Id::as_ptr(&s) as _)
+        self.inner.ns_screen(mtm).map(|s| objc2::rc::Retained::as_ptr(&s) as _)
     }
 }
 
@@ -395,28 +396,44 @@ pub trait ActiveEventLoopExtMacOS {
     fn allows_automatic_window_tabbing(&self) -> bool;
 }
 
-impl ActiveEventLoopExtMacOS for ActiveEventLoop {
+impl ActiveEventLoopExtMacOS for &dyn ActiveEventLoop {
     fn hide_application(&self) {
-        self.p.hide_application()
+        let event_loop = self
+            .as_any()
+            .downcast_ref::<crate::platform_impl::ActiveEventLoop>()
+            .expect("non macOS event loop on macOS");
+        event_loop.hide_application()
     }
 
     fn hide_other_applications(&self) {
-        self.p.hide_other_applications()
+        let event_loop = self
+            .as_any()
+            .downcast_ref::<crate::platform_impl::ActiveEventLoop>()
+            .expect("non macOS event loop on macOS");
+        event_loop.hide_other_applications()
     }
 
     fn set_allows_automatic_window_tabbing(&self, enabled: bool) {
-        self.p.set_allows_automatic_window_tabbing(enabled);
+        let event_loop = self
+            .as_any()
+            .downcast_ref::<crate::platform_impl::ActiveEventLoop>()
+            .expect("non macOS event loop on macOS");
+        event_loop.set_allows_automatic_window_tabbing(enabled);
     }
 
     fn allows_automatic_window_tabbing(&self) -> bool {
-        self.p.allows_automatic_window_tabbing()
+        let event_loop = self
+            .as_any()
+            .downcast_ref::<crate::platform_impl::ActiveEventLoop>()
+            .expect("non macOS event loop on macOS");
+        event_loop.allows_automatic_window_tabbing()
     }
 }
 
 /// Option as alt behavior.
 ///
 /// The default is `None`.
-#[derive(Default, Debug, Clone, Copy, PartialEq, Eq)]
+#[derive(Default, Debug, Clone, Copy, PartialEq, Eq, Hash)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 pub enum OptionAsAlt {
     /// The left `Option` key is treated as `Alt`.

src/platform/pump_events.rs

@@ -1,14 +1,10 @@
 use std::time::Duration;
 
 use crate::application::ApplicationHandler;
-use crate::event::Event;
-use crate::event_loop::{self, ActiveEventLoop, EventLoop};
+use crate::event_loop::EventLoop;
 
 /// Additional methods on [`EventLoop`] for pumping events within an external event loop
 pub trait EventLoopExtPumpEvents {
-    /// A type provided by the user that can be passed through [`Event::UserEvent`].
-    type UserEvent: 'static;
-
     /// Pump the `EventLoop` to check for and dispatch pending events.
     ///
     /// This API is designed to enable applications to integrate Winit into an
@@ -52,18 +48,18 @@ pub trait EventLoopExtPumpEvents {
     /// - `RedrawRequested` events, used to schedule rendering.
     ///
     ///     macOS for example uses a `drawRect` callback to drive rendering
-    /// within applications and expects rendering to be finished before
-    /// the `drawRect` callback returns.
+    ///     within applications and expects rendering to be finished before
+    ///     the `drawRect` callback returns.
     ///
     ///     For portability it's strongly recommended that applications should
-    /// keep their rendering inside the closure provided to Winit.
+    ///     keep their rendering inside the closure provided to Winit.
     /// - Any lifecycle events, such as `Suspended` / `Resumed`.
     ///
     ///     The handling of these events needs to be synchronized with the
-    /// operating system and it would never be appropriate to buffer a
-    /// notification that your application has been suspended or resumed and
-    /// then handled that later since there would always be a chance that
-    /// other lifecycle events occur while the event is buffered.
+    ///     operating system and it would never be appropriate to buffer a
+    ///     notification that your application has been suspended or resumed and
+    ///     then handled that later since there would always be a chance that
+    ///     other lifecycle events occur while the event is buffered.
     ///
     /// ## Supported Platforms
     ///
@@ -74,13 +70,13 @@ pub trait EventLoopExtPumpEvents {
     ///
     /// ## Unsupported Platforms
     ///
-    /// - **Web:**  This API is fundamentally incompatible with the event-based way in which
-    /// Web browsers work because it's not possible to have a long-running external
-    /// loop that would block the browser and there is nothing that can be
-    /// polled to ask for new new events. Events are delivered via callbacks based
-    /// on an event loop that is internal to the browser itself.
+    /// - **Web:**  This API is fundamentally incompatible with the event-based way in which Web
+    ///   browsers work because it's not possible to have a long-running external loop that would
+    ///   block the browser and there is nothing that can be polled to ask for new new events.
+    ///   Events are delivered via callbacks based on an event loop that is internal to the browser
+    ///   itself.
     /// - **iOS:** It's not possible to stop and start an `NSApplication` repeatedly on iOS so
-    /// there's no way to support the same approach to polling as on MacOS.
+    ///   there's no way to support the same approach to polling as on MacOS.
     ///
     /// ## Platform-specific
     ///
@@ -103,38 +99,25 @@ pub trait EventLoopExtPumpEvents {
     ///   If you render outside of Winit you are likely to see window resizing artifacts
     ///   since MacOS expects applications to render synchronously during any `drawRect`
     ///   callback.
-    fn pump_app_events<A: ApplicationHandler<Self::UserEvent>>(
+    fn pump_app_events<A: ApplicationHandler>(
         &mut self,
         timeout: Option<Duration>,
-        app: &mut A,
-    ) -> PumpStatus {
-        #[allow(deprecated)]
-        self.pump_events(timeout, |event, event_loop| {
-            event_loop::dispatch_event_for_app(app, event_loop, event)
-        })
-    }
-
-    /// See [`pump_app_events`].
-    ///
-    /// [`pump_app_events`]: Self::pump_app_events
-    #[deprecated = "use EventLoopExtPumpEvents::pump_app_events"]
-    fn pump_events<F>(&mut self, timeout: Option<Duration>, event_handler: F) -> PumpStatus
-    where
-        F: FnMut(Event<Self::UserEvent>, &ActiveEventLoop);
+        app: A,
+    ) -> PumpStatus;
 }
 
-impl<T> EventLoopExtPumpEvents for EventLoop<T> {
-    type UserEvent = T;
-
-    fn pump_events<F>(&mut self, timeout: Option<Duration>, event_handler: F) -> PumpStatus
-    where
-        F: FnMut(Event<Self::UserEvent>, &ActiveEventLoop),
-    {
-        self.event_loop.pump_events(timeout, event_handler)
+impl EventLoopExtPumpEvents for EventLoop {
+    fn pump_app_events<A: ApplicationHandler>(
+        &mut self,
+        timeout: Option<Duration>,
+        app: A,
+    ) -> PumpStatus {
+        self.event_loop.pump_app_events(timeout, app)
     }
 }
 
 /// The return status for `pump_events`
+#[derive(Clone, Copy, Debug, Eq, Hash, PartialEq)]
 pub enum PumpStatus {
     /// Continue running external loop.
     Continue,

src/platform/run_on_demand.rs

@@ -1,24 +1,13 @@
 use crate::application::ApplicationHandler;
 use crate::error::EventLoopError;
-use crate::event::Event;
-use crate::event_loop::{self, ActiveEventLoop, EventLoop};
-
+use crate::event_loop::EventLoop;
 #[cfg(doc)]
-use crate::{platform::pump_events::EventLoopExtPumpEvents, window::Window};
+use crate::{
+    event_loop::ActiveEventLoop, platform::pump_events::EventLoopExtPumpEvents, window::Window,
+};
 
 /// Additional methods on [`EventLoop`] to return control flow to the caller.
 pub trait EventLoopExtRunOnDemand {
-    /// A type provided by the user that can be passed through [`Event::UserEvent`].
-    type UserEvent: 'static;
-
-    /// See [`run_app_on_demand`].
-    ///
-    /// [`run_app_on_demand`]: Self::run_app_on_demand
-    #[deprecated = "use EventLoopExtRunOnDemand::run_app_on_demand"]
-    fn run_on_demand<F>(&mut self, event_handler: F) -> Result<(), EventLoopError>
-    where
-        F: FnMut(Event<Self::UserEvent>, &ActiveEventLoop);
-
     /// Run the application with the event loop on the calling thread.
     ///
     /// Unlike [`EventLoop::run_app`], this function accepts non-`'static` (i.e. non-`move`)
@@ -42,7 +31,13 @@ pub trait EventLoopExtRunOnDemand {
     /// # Caveats
     /// - This extension isn't available on all platforms, since it's not always possible to return
     ///   to the caller (specifically this is impossible on iOS and Web - though with the Web
-    ///   backend it is possible to use `EventLoopExtWebSys::spawn()`[^1] more than once instead).
+    ///   backend it is possible to use
+    #[cfg_attr(
+        any(web_platform, docsrs),
+        doc = "  [`EventLoopExtWeb::spawn_app()`][crate::platform::web::EventLoopExtWeb::spawn_app()]"
+    )]
+    #[cfg_attr(not(any(web_platform, docsrs)), doc = "  `EventLoopExtWeb::spawn_app()`")]
+    ///   [^1] more than once instead).
     /// - No [`Window`] state can be carried between separate runs of the event loop.
     ///
     /// You are strongly encouraged to use [`EventLoop::run_app()`] for portability, unless you
@@ -60,38 +55,17 @@ pub trait EventLoopExtRunOnDemand {
     ///   block the browser and there is nothing that can be polled to ask for new events. Events
     ///   are delivered via callbacks based on an event loop that is internal to the browser itself.
     /// - **iOS:** It's not possible to stop and start an `UIApplication` repeatedly on iOS.
-    #[cfg_attr(not(web_platform), doc = "[^1]: `spawn()` is only available on `wasm` platforms.")]
-    #[rustfmt::skip]
+    ///
+    /// [^1]: `spawn_app()` is only available on the Web platforms.
     ///
     /// [`exit()`]: ActiveEventLoop::exit()
     /// [`set_control_flow()`]: ActiveEventLoop::set_control_flow()
-    fn run_app_on_demand<A: ApplicationHandler<Self::UserEvent>>(
-        &mut self,
-        app: &mut A,
-    ) -> Result<(), EventLoopError> {
-        #[allow(deprecated)]
-        self.run_on_demand(|event, event_loop| {
-            event_loop::dispatch_event_for_app(app, event_loop, event)
-        })
-    }
+    fn run_app_on_demand<A: ApplicationHandler>(&mut self, app: A) -> Result<(), EventLoopError>;
 }
 
-impl<T> EventLoopExtRunOnDemand for EventLoop<T> {
-    type UserEvent = T;
-
-    fn run_on_demand<F>(&mut self, event_handler: F) -> Result<(), EventLoopError>
-    where
-        F: FnMut(Event<Self::UserEvent>, &ActiveEventLoop),
-    {
-        self.event_loop.window_target().clear_exit();
-        self.event_loop.run_on_demand(event_handler)
-    }
-}
-
-impl ActiveEventLoop {
-    /// Clear exit status.
-    pub(crate) fn clear_exit(&self) {
-        self.p.clear_exit()
+impl EventLoopExtRunOnDemand for EventLoop {
+    fn run_app_on_demand<A: ApplicationHandler>(&mut self, app: A) -> Result<(), EventLoopError> {
+        self.event_loop.run_app_on_demand(app)
     }
 }
 

src/platform/startup_notify.rs

@@ -25,6 +25,8 @@ use std::env;
 
 use crate::error::NotSupportedError;
 use crate::event_loop::{ActiveEventLoop, AsyncRequestSerial};
+#[cfg(wayland_platform)]
+use crate::platform::wayland::ActiveEventLoopExtWayland;
 use crate::window::{ActivationToken, Window, WindowAttributes};
 
 /// The variable which is used mostly on X11.
@@ -55,16 +57,18 @@ pub trait WindowAttributesExtStartupNotify {
     fn with_activation_token(self, token: ActivationToken) -> Self;
 }
 
-impl EventLoopExtStartupNotify for ActiveEventLoop {
+impl EventLoopExtStartupNotify for &dyn ActiveEventLoop {
     fn read_token_from_env(&self) -> Option<ActivationToken> {
-        match self.p {
-            #[cfg(wayland_platform)]
-            crate::platform_impl::ActiveEventLoop::Wayland(_) => env::var(WAYLAND_VAR),
-            #[cfg(x11_platform)]
-            crate::platform_impl::ActiveEventLoop::X(_) => env::var(X11_VAR),
+        #[cfg(x11_platform)]
+        let _is_wayland = false;
+        #[cfg(wayland_platform)]
+        let _is_wayland = self.is_wayland();
+
+        if _is_wayland {
+            env::var(WAYLAND_VAR).ok().map(ActivationToken::_new)
+        } else {
+            env::var(X11_VAR).ok().map(ActivationToken::_new)
         }
-        .ok()
-        .map(ActivationToken::_new)
     }
 }
 

src/platform/wayland.rs

@@ -13,11 +13,11 @@
 //! * `wayland-csd-adwaita` (default).
 //! * `wayland-csd-adwaita-crossfont`.
 //! * `wayland-csd-adwaita-notitle`.
-use crate::event_loop::{ActiveEventLoop, EventLoopBuilder};
+use crate::application::ApplicationHandler;
+use crate::event_loop::{ActiveEventLoop, EventLoop, EventLoopBuilder};
 use crate::monitor::MonitorHandle;
-use crate::window::{Window, WindowAttributes};
-
 pub use crate::window::Theme;
+use crate::window::{Window, WindowAttributes};
 
 /// Additional methods on [`ActiveEventLoop`] that are specific to Wayland.
 pub trait ActiveEventLoopExtWayland {
@@ -25,10 +25,45 @@ pub trait ActiveEventLoopExtWayland {
     fn is_wayland(&self) -> bool;
 }
 
-impl ActiveEventLoopExtWayland for ActiveEventLoop {
+pub trait WaylandApplicationHandler: ApplicationHandler + 'static {
+    fn wayland_callback(&mut self);
+}
+
+impl ActiveEventLoopExtWayland for &dyn ActiveEventLoop {
     #[inline]
     fn is_wayland(&self) -> bool {
-        self.p.is_wayland()
+        self.as_any().downcast_ref::<crate::platform_impl::wayland::ActiveEventLoop>().is_some()
+    }
+}
+
+/// Additional methods on [`EventLoop`] that are specific to Wayland.
+pub trait EventLoopExtWayland {
+    /// True if the [`EventLoop`] uses Wayland.
+    fn is_wayland(&self) -> bool;
+
+    fn register_wayland_callback<T: WaylandApplicationHandler>(&mut self);
+}
+
+impl EventLoopExtWayland for EventLoop {
+    #[inline]
+    fn is_wayland(&self) -> bool {
+        self.event_loop.is_wayland()
+    }
+
+    fn register_wayland_callback<T: WaylandApplicationHandler>(&mut self) {
+        let event_loop = match &self.event_loop {
+            crate::platform_impl::EventLoop::Wayland(event_loop) => &event_loop.active_event_loop,
+            #[cfg(x11_platform)]
+            crate::platform_impl::EventLoop::X(_) => return,
+        };
+
+        event_loop.wayland_callback.set(Some(|app: &mut dyn ApplicationHandler| {
+            app.as_any()
+                .expect("as_any_mut is not implemented")
+                .downcast_mut::<T>()
+                .unwrap()
+                .wayland_callback()
+        }));
     }
 }
 
@@ -44,7 +79,7 @@ pub trait EventLoopBuilderExtWayland {
     fn with_any_thread(&mut self, any_thread: bool) -> &mut Self;
 }
 
-impl<T> EventLoopBuilderExtWayland for EventLoopBuilder<T> {
+impl EventLoopBuilderExtWayland for EventLoopBuilder {
     #[inline]
     fn with_wayland(&mut self) -> &mut Self {
         self.platform_specific.forced_backend = Some(crate::platform_impl::Backend::Wayland);

src/platform/web.rs

@@ -1,24 +1,23 @@
 //! # Web
 //!
-//! The officially supported browsers are Chrome, Firefox and Safari 13.1+,
-//! though forks of these should work fine.
+//! Winit supports running in Browsers by compiling to WebAssembly with
+//! [`wasm-bindgen`][wasm_bindgen]. For information on using Rust on WebAssembly, check out the
+//! [Rust and WebAssembly book].
 //!
-//! Winit supports compiling to the `wasm32-unknown-unknown` target with
-//! `web-sys`.
+//! The officially supported browsers are Chrome, Firefox and Safari 13.1+, though forks of these
+//! should work fine.
 //!
-//! On the web platform, a Winit window is backed by a `<canvas>` element. You
-//! can either [provide Winit with a `<canvas>` element][with_canvas], or
-//! [let Winit create a `<canvas>` element which you can then retrieve][get]
-//! and insert it into the DOM yourself.
+//! On the Web platform, a Winit [`Window`] is backed by a [`HTMLCanvasElement`][canvas]. Winit will
+//! create that canvas for you or you can [provide your own][with_canvas]. Then you can either let
+//! Winit [insert it into the DOM for you][insert], or [retrieve the canvas][get] and insert it
+//! yourself.
 //!
-//! Currently, there is no example code using Winit on Web, see [#3473]. For
-//! information on using Rust on WebAssembly, check out the [Rust and
-//! WebAssembly book].
-//!
-//! [with_canvas]: WindowAttributesExtWebSys::with_canvas
-//! [get]: WindowExtWebSys::canvas
-//! [#3473]: https://github.com/rust-windowing/winit/issues/3473
-//! [Rust and WebAssembly book]: https://rustwasm.github.io/book/
+//! [canvas]: https://developer.mozilla.org/en-US/docs/Web/API/HTMLCanvasElement
+//! [with_canvas]: WindowAttributesExtWeb::with_canvas
+//! [get]: WindowExtWeb::canvas
+//! [insert]: WindowAttributesExtWeb::with_append
+#![cfg_attr(not(web_platform), doc = "[wasm_bindgen]: https://docs.rs/wasm-bindgen")]
+//! [Rust and WebAssembly book]: https://rustwasm.github.io/book
 //!
 //! ## CSS properties
 //!
@@ -43,6 +42,7 @@
 //! [`WindowEvent::Touch`]: crate::event::WindowEvent::Touch
 //! [`Window::set_outer_position()`]: crate::window::Window::set_outer_position
 
+use std::cell::Ref;
 use std::error::Error;
 use std::fmt::{self, Display, Formatter};
 use std::future::Future;
@@ -50,26 +50,35 @@ use std::pin::Pin;
 use std::task::{Context, Poll};
 use std::time::Duration;
 
+#[cfg(feature = "serde")]
+use serde::{Deserialize, Serialize};
 #[cfg(web_platform)]
 use web_sys::HtmlCanvasElement;
 
 use crate::application::ApplicationHandler;
 use crate::cursor::CustomCursorSource;
-use crate::event::Event;
-use crate::event_loop::{self, ActiveEventLoop, EventLoop};
-#[cfg(web_platform)]
-use crate::platform_impl::CustomCursorFuture as PlatformCustomCursorFuture;
+use crate::error::NotSupportedError;
+use crate::event::FingerId;
+use crate::event_loop::{ActiveEventLoop, EventLoop};
+use crate::monitor::MonitorHandle;
 use crate::platform_impl::PlatformCustomCursorSource;
+#[cfg(web_platform)]
+use crate::platform_impl::{
+    CustomCursorFuture as PlatformCustomCursorFuture,
+    HasMonitorPermissionFuture as PlatformHasMonitorPermissionFuture,
+    MonitorPermissionFuture as PlatformMonitorPermissionFuture,
+    OrientationLockFuture as PlatformOrientationLockFuture,
+};
 use crate::window::{CustomCursor, Window, WindowAttributes};
 
 #[cfg(not(web_platform))]
 #[doc(hidden)]
 pub struct HtmlCanvasElement;
 
-pub trait WindowExtWebSys {
+pub trait WindowExtWeb {
     /// Only returns the canvas if called from inside the window context (the
     /// main thread).
-    fn canvas(&self) -> Option<HtmlCanvasElement>;
+    fn canvas(&self) -> Option<Ref<'_, HtmlCanvasElement>>;
 
     /// Returns [`true`] if calling `event.preventDefault()` is enabled.
     ///
@@ -85,11 +94,19 @@ pub trait WindowExtWebSys {
     /// Some events are impossible to prevent. E.g. Firefox allows to access the native browser
     /// context menu with Shift+Rightclick.
     fn set_prevent_default(&self, prevent_default: bool);
+
+    /// Returns whether using [`CursorGrabMode::Locked`] returns raw, un-accelerated mouse input.
+    ///
+    /// This is the same as [`ActiveEventLoopExtWeb::is_cursor_lock_raw()`], and is provided for
+    /// convenience.
+    ///
+    /// [`CursorGrabMode::Locked`]: crate::window::CursorGrabMode::Locked
+    fn is_cursor_lock_raw(&self) -> bool;
 }
 
-impl WindowExtWebSys for Window {
+impl WindowExtWeb for Window {
     #[inline]
-    fn canvas(&self) -> Option<HtmlCanvasElement> {
+    fn canvas(&self) -> Option<Ref<'_, HtmlCanvasElement>> {
         self.window.canvas()
     }
 
@@ -100,13 +117,17 @@ impl WindowExtWebSys for Window {
     fn set_prevent_default(&self, prevent_default: bool) {
         self.window.set_prevent_default(prevent_default)
     }
+
+    fn is_cursor_lock_raw(&self) -> bool {
+        self.window.is_cursor_lock_raw()
+    }
 }
 
-pub trait WindowAttributesExtWebSys {
+pub trait WindowAttributesExtWeb {
     /// Pass an [`HtmlCanvasElement`] to be used for this [`Window`]. If [`None`],
     /// [`WindowAttributes::default()`] will create one.
     ///
-    /// In any case, the canvas won't be automatically inserted into the web page.
+    /// In any case, the canvas won't be automatically inserted into the Web page.
     ///
     /// [`None`] by default.
     #[cfg_attr(not(web_platform), doc = "", doc = "[`HtmlCanvasElement`]: #only-available-on-wasm")]
@@ -126,13 +147,13 @@ pub trait WindowAttributesExtWebSys {
     /// Enabled by default.
     fn with_focusable(self, focusable: bool) -> Self;
 
-    /// On window creation, append the canvas element to the web page if it isn't already.
+    /// On window creation, append the canvas element to the Web page if it isn't already.
     ///
     /// Disabled by default.
     fn with_append(self, append: bool) -> Self;
 }
 
-impl WindowAttributesExtWebSys for WindowAttributes {
+impl WindowAttributesExtWeb for WindowAttributes {
     fn with_canvas(mut self, canvas: Option<HtmlCanvasElement>) -> Self {
         self.platform_specific.set_canvas(canvas);
         self
@@ -154,11 +175,8 @@ impl WindowAttributesExtWebSys for WindowAttributes {
     }
 }
 
-/// Additional methods on `EventLoop` that are specific to the web.
-pub trait EventLoopExtWebSys {
-    /// A type provided by the user that can be passed through `Event::UserEvent`.
-    type UserEvent: 'static;
-
+/// Additional methods on `EventLoop` that are specific to the Web.
+pub trait EventLoopExtWeb {
     /// Initializes the winit event loop.
     ///
     /// Unlike
@@ -180,36 +198,9 @@ pub trait EventLoopExtWebSys {
         not(all(web_platform, target_feature = "exception-handling")),
         doc = "[`run_app()`]: EventLoop::run_app()"
     )]
-    /// [^1]: `run_app()` is _not_ available on WASM when the target supports `exception-handling`.
-    fn spawn_app<A: ApplicationHandler<Self::UserEvent> + 'static>(self, app: A);
+    /// [^1]: `run_app()` is _not_ available on Wasm when the target supports `exception-handling`.
+    fn spawn_app<A: ApplicationHandler + 'static>(self, app: A);
 
-    /// See [`spawn_app`].
-    ///
-    /// [`spawn_app`]: Self::spawn_app
-    #[deprecated = "use EventLoopExtWebSys::spawn_app"]
-    fn spawn<F>(self, event_handler: F)
-    where
-        F: 'static + FnMut(Event<Self::UserEvent>, &ActiveEventLoop);
-}
-
-impl<T> EventLoopExtWebSys for EventLoop<T> {
-    type UserEvent = T;
-
-    fn spawn_app<A: ApplicationHandler<Self::UserEvent> + 'static>(self, mut app: A) {
-        self.event_loop.spawn(move |event, event_loop| {
-            event_loop::dispatch_event_for_app(&mut app, event_loop, event)
-        });
-    }
-
-    fn spawn<F>(self, event_handler: F)
-    where
-        F: 'static + FnMut(Event<Self::UserEvent>, &ActiveEventLoop),
-    {
-        self.event_loop.spawn(event_handler)
-    }
-}
-
-pub trait ActiveEventLoopExtWebSys {
     /// Sets the strategy for [`ControlFlow::Poll`].
     ///
     /// See [`PollStrategy`].
@@ -224,30 +215,224 @@ pub trait ActiveEventLoopExtWebSys {
     /// [`ControlFlow::Poll`]: crate::event_loop::ControlFlow::Poll
     fn poll_strategy(&self) -> PollStrategy;
 
+    /// Sets the strategy for [`ControlFlow::WaitUntil`].
+    ///
+    /// See [`WaitUntilStrategy`].
+    ///
+    /// [`ControlFlow::WaitUntil`]: crate::event_loop::ControlFlow::WaitUntil
+    fn set_wait_until_strategy(&self, strategy: WaitUntilStrategy);
+
+    /// Gets the strategy for [`ControlFlow::WaitUntil`].
+    ///
+    /// See [`WaitUntilStrategy`].
+    ///
+    /// [`ControlFlow::WaitUntil`]: crate::event_loop::ControlFlow::WaitUntil
+    fn wait_until_strategy(&self) -> WaitUntilStrategy;
+
+    /// Returns if the users device has multiple screens. Useful to check before prompting the user
+    /// with [`EventLoopExtWeb::request_detailed_monitor_permission()`].
+    ///
+    /// Browsers might always return [`false`] to reduce fingerprinting.
+    fn has_multiple_screens(&self) -> Result<bool, NotSupportedError>;
+
+    /// Prompts the user for permission to query detailed information about available monitors. The
+    /// returned [`MonitorPermissionFuture`] can be dropped without aborting the request.
+    ///
+    /// Check [`EventLoopExtWeb::has_multiple_screens()`] before unnecessarily prompting the user
+    /// for such permissions.
+    ///
+    /// [`MonitorHandle`]s don't automatically make use of this after permission is granted. New
+    /// [`MonitorHandle`]s have to be created instead.
+    fn request_detailed_monitor_permission(&self) -> MonitorPermissionFuture;
+
+    /// Returns whether the user has given permission to access detailed monitor information.
+    ///
+    /// [`MonitorHandle`]s don't automatically make use of detailed monitor information after
+    /// permission is granted. New [`MonitorHandle`]s have to be created instead.
+    fn has_detailed_monitor_permission(&self) -> HasMonitorPermissionFuture;
+}
+
+impl EventLoopExtWeb for EventLoop {
+    fn spawn_app<A: ApplicationHandler + 'static>(self, app: A) {
+        self.event_loop.spawn_app(app);
+    }
+
+    fn set_poll_strategy(&self, strategy: PollStrategy) {
+        self.event_loop.set_poll_strategy(strategy);
+    }
+
+    fn poll_strategy(&self) -> PollStrategy {
+        self.event_loop.poll_strategy()
+    }
+
+    fn set_wait_until_strategy(&self, strategy: WaitUntilStrategy) {
+        self.event_loop.set_wait_until_strategy(strategy);
+    }
+
+    fn wait_until_strategy(&self) -> WaitUntilStrategy {
+        self.event_loop.wait_until_strategy()
+    }
+
+    fn has_multiple_screens(&self) -> Result<bool, NotSupportedError> {
+        self.event_loop.has_multiple_screens()
+    }
+
+    fn request_detailed_monitor_permission(&self) -> MonitorPermissionFuture {
+        MonitorPermissionFuture(self.event_loop.request_detailed_monitor_permission())
+    }
+
+    fn has_detailed_monitor_permission(&self) -> HasMonitorPermissionFuture {
+        HasMonitorPermissionFuture(self.event_loop.has_detailed_monitor_permission())
+    }
+}
+
+pub trait ActiveEventLoopExtWeb {
+    /// Sets the strategy for [`ControlFlow::Poll`].
+    ///
+    /// See [`PollStrategy`].
+    ///
+    /// [`ControlFlow::Poll`]: crate::event_loop::ControlFlow::Poll
+    fn set_poll_strategy(&self, strategy: PollStrategy);
+
+    /// Gets the strategy for [`ControlFlow::Poll`].
+    ///
+    /// See [`PollStrategy`].
+    ///
+    /// [`ControlFlow::Poll`]: crate::event_loop::ControlFlow::Poll
+    fn poll_strategy(&self) -> PollStrategy;
+
+    /// Sets the strategy for [`ControlFlow::WaitUntil`].
+    ///
+    /// See [`WaitUntilStrategy`].
+    ///
+    /// [`ControlFlow::WaitUntil`]: crate::event_loop::ControlFlow::WaitUntil
+    fn set_wait_until_strategy(&self, strategy: WaitUntilStrategy);
+
+    /// Gets the strategy for [`ControlFlow::WaitUntil`].
+    ///
+    /// See [`WaitUntilStrategy`].
+    ///
+    /// [`ControlFlow::WaitUntil`]: crate::event_loop::ControlFlow::WaitUntil
+    fn wait_until_strategy(&self) -> WaitUntilStrategy;
+
     /// Async version of [`ActiveEventLoop::create_custom_cursor()`] which waits until the
     /// cursor has completely finished loading.
     fn create_custom_cursor_async(&self, source: CustomCursorSource) -> CustomCursorFuture;
+
+    /// Returns whether using [`CursorGrabMode::Locked`] returns raw, un-accelerated mouse input.
+    ///
+    /// [`CursorGrabMode::Locked`]: crate::window::CursorGrabMode::Locked
+    fn is_cursor_lock_raw(&self) -> bool;
+
+    /// Returns if the users device has multiple screens. Useful to check before prompting the user
+    /// with [`EventLoopExtWeb::request_detailed_monitor_permission()`].
+    ///
+    /// Browsers might always return [`false`] to reduce fingerprinting.
+    fn has_multiple_screens(&self) -> Result<bool, NotSupportedError>;
+
+    /// Prompts the user for permission to query detailed information about available monitors. The
+    /// returned [`MonitorPermissionFuture`] can be dropped without aborting the request.
+    ///
+    /// Check [`EventLoopExtWeb::has_multiple_screens()`] before unnecessarily prompting the user
+    /// for such permissions.
+    ///
+    /// [`MonitorHandle`]s don't automatically make use of this after permission is granted. New
+    /// [`MonitorHandle`]s have to be created instead.
+    fn request_detailed_monitor_permission(&self) -> MonitorPermissionFuture;
+
+    /// Returns whether the user has given permission to access detailed monitor information.
+    ///
+    /// [`MonitorHandle`]s don't automatically make use of detailed monitor information after
+    /// permission is granted. New [`MonitorHandle`]s have to be created instead.
+    fn has_detailed_monitor_permission(&self) -> bool;
 }
 
-impl ActiveEventLoopExtWebSys for ActiveEventLoop {
+impl ActiveEventLoopExtWeb for &dyn ActiveEventLoop {
     #[inline]
     fn create_custom_cursor_async(&self, source: CustomCursorSource) -> CustomCursorFuture {
-        self.p.create_custom_cursor_async(source)
+        let event_loop = self
+            .as_any()
+            .downcast_ref::<crate::platform_impl::ActiveEventLoop>()
+            .expect("non Web event loop on Web");
+        event_loop.create_custom_cursor_async(source)
     }
 
     #[inline]
     fn set_poll_strategy(&self, strategy: PollStrategy) {
-        self.p.set_poll_strategy(strategy);
+        let event_loop = self
+            .as_any()
+            .downcast_ref::<crate::platform_impl::ActiveEventLoop>()
+            .expect("non Web event loop on Web");
+        event_loop.set_poll_strategy(strategy);
     }
 
     #[inline]
     fn poll_strategy(&self) -> PollStrategy {
-        self.p.poll_strategy()
+        let event_loop = self
+            .as_any()
+            .downcast_ref::<crate::platform_impl::ActiveEventLoop>()
+            .expect("non Web event loop on Web");
+        event_loop.poll_strategy()
+    }
+
+    #[inline]
+    fn set_wait_until_strategy(&self, strategy: WaitUntilStrategy) {
+        let event_loop = self
+            .as_any()
+            .downcast_ref::<crate::platform_impl::ActiveEventLoop>()
+            .expect("non Web event loop on Web");
+        event_loop.set_wait_until_strategy(strategy);
+    }
+
+    #[inline]
+    fn wait_until_strategy(&self) -> WaitUntilStrategy {
+        let event_loop = self
+            .as_any()
+            .downcast_ref::<crate::platform_impl::ActiveEventLoop>()
+            .expect("non Web event loop on Web");
+        event_loop.wait_until_strategy()
+    }
+
+    #[inline]
+    fn is_cursor_lock_raw(&self) -> bool {
+        let event_loop = self
+            .as_any()
+            .downcast_ref::<crate::platform_impl::ActiveEventLoop>()
+            .expect("non Web event loop on Web");
+        event_loop.is_cursor_lock_raw()
+    }
+
+    #[inline]
+    fn has_multiple_screens(&self) -> Result<bool, NotSupportedError> {
+        let event_loop = self
+            .as_any()
+            .downcast_ref::<crate::platform_impl::ActiveEventLoop>()
+            .expect("non Web event loop on Web");
+        event_loop.has_multiple_screens()
+    }
+
+    #[inline]
+    fn request_detailed_monitor_permission(&self) -> MonitorPermissionFuture {
+        let event_loop = self
+            .as_any()
+            .downcast_ref::<crate::platform_impl::ActiveEventLoop>()
+            .expect("non Web event loop on Web");
+        MonitorPermissionFuture(event_loop.request_detailed_monitor_permission())
+    }
+
+    #[inline]
+    fn has_detailed_monitor_permission(&self) -> bool {
+        let event_loop = self
+            .as_any()
+            .downcast_ref::<crate::platform_impl::ActiveEventLoop>()
+            .expect("non Web event loop on Web");
+        event_loop.has_detailed_monitor_permission()
     }
 }
 
 /// Strategy used for [`ControlFlow::Poll`][crate::event_loop::ControlFlow::Poll].
-#[derive(Clone, Copy, Debug, Default, PartialEq, Eq)]
+#[derive(Clone, Copy, Debug, Default, Eq, Hash, PartialEq)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 pub enum PollStrategy {
     /// Uses [`Window.requestIdleCallback()`] to queue the next event loop. If not available
     /// this will fallback to [`setTimeout()`].
@@ -272,7 +457,31 @@ pub enum PollStrategy {
     Scheduler,
 }
 
-pub trait CustomCursorExtWebSys {
+/// Strategy used for [`ControlFlow::WaitUntil`][crate::event_loop::ControlFlow::WaitUntil].
+#[derive(Clone, Copy, Debug, Default, Eq, Hash, PartialEq)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
+pub enum WaitUntilStrategy {
+    /// Uses the [Prioritized Task Scheduling API] to queue the next event loop. If not available
+    /// this will fallback to [`setTimeout()`].
+    ///
+    /// This strategy is commonly not affected by browser throttling unless the window is not
+    /// focused.
+    ///
+    /// This is the default strategy.
+    ///
+    /// [Prioritized Task Scheduling API]: https://developer.mozilla.org/en-US/docs/Web/API/Prioritized_Task_Scheduling_API
+    /// [`setTimeout()`]: https://developer.mozilla.org/en-US/docs/Web/API/setTimeout
+    #[default]
+    Scheduler,
+    /// Equal to [`Scheduler`][Self::Scheduler] but wakes up the event loop from a [worker].
+    ///
+    /// This strategy is commonly not affected by browser throttling regardless of window focus.
+    ///
+    /// [worker]: https://developer.mozilla.org/en-US/docs/Web/API/Web_Workers_API
+    Worker,
+}
+
+pub trait CustomCursorExtWeb {
     /// Returns if this cursor is an animation.
     fn is_animation(&self) -> bool;
 
@@ -291,7 +500,7 @@ pub trait CustomCursorExtWebSys {
     ) -> Result<CustomCursorSource, BadAnimation>;
 }
 
-impl CustomCursorExtWebSys for CustomCursor {
+impl CustomCursorExtWeb for CustomCursor {
     fn is_animation(&self) -> bool {
         self.inner.animation
     }
@@ -319,7 +528,8 @@ impl CustomCursorExtWebSys for CustomCursor {
 }
 
 /// An error produced when using [`CustomCursor::from_animation`] with invalid arguments.
-#[derive(Debug, Clone)]
+#[derive(Clone, Copy, Debug, Eq, Hash, PartialEq)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 pub enum BadAnimation {
     /// Produced when no cursors were supplied.
     Empty,
@@ -331,7 +541,7 @@ impl fmt::Display for BadAnimation {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         match self {
             Self::Empty => write!(f, "No cursors supplied"),
-            Self::Animation => write!(f, "A supplied cursor is an animtion"),
+            Self::Animation => write!(f, "A supplied cursor is an animation"),
         }
     }
 }
@@ -352,11 +562,11 @@ impl Future for CustomCursorFuture {
     }
 }
 
-#[derive(Clone, Debug)]
+#[derive(Clone, Debug, Eq, Hash, PartialEq)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 pub enum CustomCursorError {
     Blob,
     Decode(String),
-    Animation,
 }
 
 impl Display for CustomCursorError {
@@ -364,9 +574,212 @@ impl Display for CustomCursorError {
         match self {
             Self::Blob => write!(f, "failed to create `Blob`"),
             Self::Decode(error) => write!(f, "failed to decode image: {error}"),
-            Self::Animation => {
-                write!(f, "found `CustomCursor` that is an animation when building an animation")
+        }
+    }
+}
+
+impl Error for CustomCursorError {}
+
+#[cfg(not(web_platform))]
+struct PlatformMonitorPermissionFuture;
+
+/// Can be dropped without aborting the request for detailed monitor permissions.
+#[derive(Debug)]
+pub struct MonitorPermissionFuture(pub(crate) PlatformMonitorPermissionFuture);
+
+impl Future for MonitorPermissionFuture {
+    type Output = Result<(), MonitorPermissionError>;
+
+    fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
+        Pin::new(&mut self.0).poll(cx)
+    }
+}
+
+#[derive(Clone, Copy, Debug, Eq, Hash, PartialEq)]
+pub enum MonitorPermissionError {
+    /// User has explicitly denied permission to query detailed monitor information.
+    Denied,
+    /// User has not decided to give permission to query detailed monitor information.
+    Prompt,
+    /// Browser does not support detailed monitor information.
+    Unsupported,
+}
+
+impl Display for MonitorPermissionError {
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
+        match self {
+            MonitorPermissionError::Denied => write!(
+                f,
+                "User has explicitly denied permission to query detailed monitor information"
+            ),
+            MonitorPermissionError::Prompt => write!(
+                f,
+                "User has not decided to give permission to query detailed monitor information"
+            ),
+            MonitorPermissionError::Unsupported => {
+                write!(f, "Browser does not support detailed monitor information")
             },
         }
     }
 }
+
+impl Error for MonitorPermissionError {}
+
+#[cfg(not(web_platform))]
+struct PlatformHasMonitorPermissionFuture;
+
+#[derive(Debug)]
+pub struct HasMonitorPermissionFuture(PlatformHasMonitorPermissionFuture);
+
+impl Future for HasMonitorPermissionFuture {
+    type Output = bool;
+
+    fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
+        Pin::new(&mut self.0).poll(cx)
+    }
+}
+
+/// Additional methods on [`MonitorHandle`] that are specific to the Web.
+pub trait MonitorHandleExtWeb {
+    /// Returns whether the screen is internal to the device or external.
+    ///
+    /// External devices are generally manufactured separately from the device they are attached to
+    /// and can be connected and disconnected as needed, whereas internal screens are part of
+    /// the device and not intended to be disconnected.
+    fn is_internal(&self) -> Option<bool>;
+
+    /// Returns screen orientation data for this monitor.
+    fn orientation(&self) -> OrientationData;
+
+    /// Lock the screen orientation. The returned [`OrientationLockFuture`] can be dropped without
+    /// aborting the request.
+    ///
+    /// Will fail if another locking call is in progress.
+    fn request_lock(&self, orientation: OrientationLock) -> OrientationLockFuture;
+
+    /// Unlock the screen orientation.
+    ///
+    /// Will fail if a locking call is in progress.
+    fn unlock(&self) -> Result<(), OrientationLockError>;
+
+    /// Returns whether this [`MonitorHandle`] was created using detailed monitor permissions. If
+    /// [`false`] will always represent the current monitor the browser window is in instead of a
+    /// specific monitor.
+    ///
+    /// See [`ActiveEventLoopExtWeb::request_detailed_monitor_permission()`].
+    fn is_detailed(&self) -> bool;
+}
+
+impl MonitorHandleExtWeb for MonitorHandle {
+    fn is_internal(&self) -> Option<bool> {
+        self.inner.is_internal()
+    }
+
+    fn orientation(&self) -> OrientationData {
+        self.inner.orientation()
+    }
+
+    fn request_lock(&self, orientation_lock: OrientationLock) -> OrientationLockFuture {
+        OrientationLockFuture(self.inner.request_lock(orientation_lock))
+    }
+
+    fn unlock(&self) -> Result<(), OrientationLockError> {
+        self.inner.unlock()
+    }
+
+    fn is_detailed(&self) -> bool {
+        self.inner.is_detailed()
+    }
+}
+
+/// Screen orientation data.
+#[derive(Clone, Copy, Debug, Eq, Hash, PartialEq)]
+pub struct OrientationData {
+    /// The orientation.
+    pub orientation: Orientation,
+    /// [`true`] if the [`orientation`](Self::orientation) is flipped upside down.
+    pub flipped: bool,
+    /// [`true`] if the [`Orientation`] is the most natural one for the screen regardless of being
+    /// flipped. Computer monitors are commonly naturally landscape mode, while mobile phones
+    /// are commonly naturally portrait mode.
+    pub natural: bool,
+}
+
+/// Screen orientation.
+#[derive(Clone, Copy, Debug, Eq, Hash, PartialEq)]
+pub enum Orientation {
+    /// The screen's aspect ratio has a width greater than the height.
+    Landscape,
+    /// The screen's aspect ratio has a height greater than the width.
+    Portrait,
+}
+
+/// Screen orientation lock options. Reoresents which orientations a user can use.
+#[derive(Clone, Copy, Debug, Eq, Hash, PartialEq)]
+pub enum OrientationLock {
+    /// User is free to use any orientation.
+    Any,
+    /// User is locked to the most upright natural orientation for the screen. Computer monitors
+    /// are commonly naturally landscape mode, while mobile phones are commonly
+    /// naturally portrait mode.
+    Natural,
+    /// User is locked to landscape mode.
+    Landscape {
+        /// - [`None`]: User is locked to both upright or upside down landscape mode.
+        /// - [`false`]: User is locked to upright landscape mode.
+        /// - [`false`]: User is locked to upside down landscape mode.
+        flipped: Option<bool>,
+    },
+    /// User is locked to portrait mode.
+    Portrait {
+        /// - [`None`]: User is locked to both upright or upside down portrait mode.
+        /// - [`false`]: User is locked to upright portrait mode.
+        /// - [`false`]: User is locked to upside down portrait mode.
+        flipped: Option<bool>,
+    },
+}
+
+#[cfg(not(web_platform))]
+struct PlatformOrientationLockFuture;
+
+/// Can be dropped without aborting the request to lock the screen.
+#[derive(Debug)]
+pub struct OrientationLockFuture(PlatformOrientationLockFuture);
+
+impl Future for OrientationLockFuture {
+    type Output = Result<(), OrientationLockError>;
+
+    fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
+        Pin::new(&mut self.0).poll(cx)
+    }
+}
+
+#[derive(Clone, Copy, Debug, Eq, Hash, PartialEq)]
+pub enum OrientationLockError {
+    Unsupported,
+    Busy,
+}
+
+impl Display for OrientationLockError {
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
+        match self {
+            Self::Unsupported => write!(f, "Locking the screen orientation is not supported"),
+            Self::Busy => write!(f, "Another locking call is in progress"),
+        }
+    }
+}
+
+impl Error for OrientationLockError {}
+
+/// Additional methods on [`FingerId`] that are specific to Web.
+pub trait FingerIdExtWeb {
+    /// Indicates if the finger represents the first contact in a multi-touch interaction.
+    #[allow(clippy::wrong_self_convention)]
+    fn is_primary(self) -> bool;
+}
+
+impl FingerIdExtWeb for FingerId {
+    fn is_primary(self) -> bool {
+        self.0.is_primary()
+    }
+}

src/platform/windows.rs

@@ -6,8 +6,11 @@ use std::borrow::Borrow;
 use std::ffi::c_void;
 use std::path::Path;
 
+#[cfg(feature = "serde")]
+use serde::{Deserialize, Serialize};
+
 use crate::dpi::PhysicalSize;
-use crate::event::DeviceId;
+use crate::event::{DeviceId, FingerId};
 use crate::event_loop::EventLoopBuilder;
 use crate::monitor::MonitorHandle;
 use crate::window::{BadIcon, Icon, Window, WindowAttributes};
@@ -25,6 +28,7 @@ pub type HMONITOR = isize;
 ///
 /// [`DWM_SYSTEMBACKDROP_TYPE docs`]: https://learn.microsoft.com/en-us/windows/win32/api/dwmapi/ne-dwmapi-dwm_systembackdrop_type
 #[derive(Debug, Default, Clone, Copy, PartialEq, Eq, Hash)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 pub enum BackdropType {
     /// Corresponds to `DWMSBT_AUTO`.
     ///
@@ -54,6 +58,7 @@ pub enum BackdropType {
 /// Describes a color used by Windows
 #[repr(transparent)]
 #[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 pub struct Color(u32);
 
 impl Color {
@@ -82,6 +87,7 @@ impl Default for Color {
 /// [`DWM_WINDOW_CORNER_PREFERENCE docs`]: https://learn.microsoft.com/en-us/windows/win32/api/dwmapi/ne-dwmapi-dwm_window_corner_preference
 #[repr(i32)]
 #[derive(Debug, Default, Clone, Copy, PartialEq, Eq, Hash)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 pub enum CornerPreference {
     /// Corresponds to `DWMWCP_DEFAULT`.
     ///
@@ -108,7 +114,7 @@ pub enum CornerPreference {
 /// A wrapper around a [`Window`] that ignores thread-specific window handle limitations.
 ///
 /// See [`WindowBorrowExtWindows::any_thread`] for more information.
-#[derive(Debug)]
+#[derive(Clone, Debug)]
 pub struct AnyThread<W>(W);
 
 impl<W: Borrow<Window>> AnyThread<W> {
@@ -183,11 +189,11 @@ pub trait EventLoopBuilderExtWindows {
     /// Disable process-wide DPI awareness.
     ///
     /// ```
-    /// use winit::event_loop::EventLoopBuilder;
+    /// use winit::event_loop::EventLoop;
     /// #[cfg(target_os = "windows")]
     /// use winit::platform::windows::EventLoopBuilderExtWindows;
     ///
-    /// let mut builder = EventLoopBuilder::new();
+    /// let mut builder = EventLoop::builder();
     /// #[cfg(target_os = "windows")]
     /// builder.with_dpi_aware(false);
     /// # if false { // We can't test this part
@@ -203,11 +209,11 @@ pub trait EventLoopBuilderExtWindows {
     ///
     /// ```
     /// # use windows_sys::Win32::UI::WindowsAndMessaging::{ACCEL, CreateAcceleratorTableW, TranslateAcceleratorW, DispatchMessageW, TranslateMessage, MSG};
-    /// use winit::event_loop::EventLoopBuilder;
+    /// use winit::event_loop::EventLoop;
     /// #[cfg(target_os = "windows")]
     /// use winit::platform::windows::EventLoopBuilderExtWindows;
     ///
-    /// let mut builder = EventLoopBuilder::new();
+    /// let mut builder = EventLoop::builder();
     /// #[cfg(target_os = "windows")]
     /// builder.with_msg_hook(|msg|{
     ///     let msg = msg as *const MSG;
@@ -227,7 +233,7 @@ pub trait EventLoopBuilderExtWindows {
         F: FnMut(*const c_void) -> bool + 'static;
 }
 
-impl<T> EventLoopBuilderExtWindows for EventLoopBuilder<T> {
+impl EventLoopBuilderExtWindows for EventLoopBuilder {
     #[inline]
     fn with_any_thread(&mut self, any_thread: bool) -> &mut Self {
         self.platform_specific.any_thread = any_thread;
@@ -337,6 +343,7 @@ pub trait WindowExtWindows {
     /// # use winit::window::Window;
     /// # fn scope(window: Window) {
     /// use std::thread;
+    ///
     /// use winit::platform::windows::WindowExtWindows;
     /// use winit::raw_window_handle::HasWindowHandle;
     ///
@@ -439,9 +446,17 @@ pub trait WindowBorrowExtWindows: Borrow<Window> + Sized {
     /// It is the responsibility of the user to only pass the window handle into thread-safe
     /// Win32 APIs.
     ///
-    /// [`window_handle_any_thread`]: WindowExtWindows::window_handle_any_thread
     /// [`Window`]: crate::window::Window
-    /// [`HasWindowHandle`]: rwh_06::HasWindowHandle
+    #[cfg_attr(
+        feature = "rwh_06",
+        doc = "[`HasWindowHandle`]: rwh_06::HasWindowHandle",
+        doc = "[`window_handle_any_thread`]: WindowExtWindows::window_handle_any_thread"
+    )]
+    #[cfg_attr(
+        not(feature = "rwh_06"),
+        doc = "[`HasWindowHandle`]: #only-available-with-rwh_06",
+        doc = "[`window_handle_any_thread`]: #only-available-with-rwh_06"
+    )]
     unsafe fn any_thread(self) -> AnyThread<Self> {
         AnyThread(self)
     }
@@ -476,10 +491,10 @@ pub trait WindowAttributesExtWindows {
     /// the menus look. If you use this, it is recommended that you combine it with
     /// `with_theme(Some(Theme::Light))` to avoid a jarring effect.
     #[cfg_attr(
-        platform_windows,
+        windows_platform,
         doc = "[`CreateMenu`]: windows_sys::Win32::UI::WindowsAndMessaging::CreateMenu"
     )]
-    #[cfg_attr(not(platform_windows), doc = "[`CreateMenu`]: #only-available-on-windows")]
+    #[cfg_attr(not(windows_platform), doc = "[`CreateMenu`]: #only-available-on-windows")]
     fn with_menu(self, menu: HMENU) -> Self;
 
     /// This sets `ICON_BIG`. A good ceiling here is 256x256.
@@ -659,6 +674,20 @@ impl DeviceIdExtWindows for DeviceId {
     }
 }
 
+/// Additional methods on `FingerId` that are specific to Windows.
+pub trait FingerIdExtWindows {
+    /// Indicates if the finger represents the first contact in a multi-touch interaction.
+    #[allow(clippy::wrong_self_convention)]
+    fn is_primary(self) -> bool;
+}
+
+impl FingerIdExtWindows for FingerId {
+    #[inline]
+    fn is_primary(self) -> bool {
+        self.0.is_primary()
+    }
+}
+
 /// Additional methods on `Icon` that are specific to Windows.
 pub trait IconExtWindows: Sized {
     /// Create an icon from a file path.

src/platform/x11.rs

@@ -2,12 +2,11 @@
 #[cfg(feature = "serde")]
 use serde::{Deserialize, Serialize};
 
-use crate::event_loop::{ActiveEventLoop, EventLoopBuilder};
+use crate::dpi::Size;
+use crate::event_loop::{ActiveEventLoop, EventLoop, EventLoopBuilder};
 use crate::monitor::MonitorHandle;
 use crate::window::{Window, WindowAttributes};
 
-use crate::dpi::Size;
-
 /// X window type. Maps directly to
 /// [`_NET_WM_WINDOW_TYPE`](https://specifications.freedesktop.org/wm-spec/wm-spec-1.5.html).
 #[derive(Debug, Default, Copy, Clone, PartialEq, Eq, Hash)]
@@ -92,10 +91,23 @@ pub trait ActiveEventLoopExtX11 {
     fn is_x11(&self) -> bool;
 }
 
-impl ActiveEventLoopExtX11 for ActiveEventLoop {
+impl ActiveEventLoopExtX11 for &dyn ActiveEventLoop {
     #[inline]
     fn is_x11(&self) -> bool {
-        !self.p.is_wayland()
+        self.as_any().downcast_ref::<crate::platform_impl::x11::ActiveEventLoop>().is_some()
+    }
+}
+
+/// Additional methods on [`EventLoop`] that are specific to X11.
+pub trait EventLoopExtX11 {
+    /// True if the [`EventLoop`] uses X11.
+    fn is_x11(&self) -> bool;
+}
+
+impl EventLoopExtX11 for EventLoop {
+    #[inline]
+    fn is_x11(&self) -> bool {
+        !self.event_loop.is_wayland()
     }
 }
 
@@ -111,7 +123,7 @@ pub trait EventLoopBuilderExtX11 {
     fn with_any_thread(&mut self, any_thread: bool) -> &mut Self;
 }
 
-impl<T> EventLoopBuilderExtX11 for EventLoopBuilder<T> {
+impl EventLoopBuilderExtX11 for EventLoopBuilder {
     #[inline]
     fn with_x11(&mut self) -> &mut Self {
         self.platform_specific.forced_backend = Some(crate::platform_impl::Backend::X);
@@ -175,7 +187,7 @@ pub trait WindowAttributesExtX11 {
     /// use winit::window::Window;
     /// use winit::event_loop::ActiveEventLoop;
     /// use winit::platform::x11::{XWindow, WindowAttributesExtX11};
-    /// # fn create_window(event_loop: &ActiveEventLoop) -> Result<(), Box<dyn std::error::Error>> {
+    /// # fn create_window(event_loop: &dyn ActiveEventLoop) -> Result<(), Box<dyn std::error::Error>> {
     /// let parent_window_id = std::env::args().nth(1).unwrap().parse::<XWindow>()?;
     /// let window_attributes = Window::default_attributes().with_embed_parent_window(parent_window_id);
     /// let window = event_loop.create_window(window_attributes)?;

src/platform_impl/android/mod.rs

@@ -1,11 +1,9 @@
-#![cfg(android_platform)]
-
+use std::any::Any;
 use std::cell::Cell;
-use std::collections::VecDeque;
 use std::hash::Hash;
-use std::marker::PhantomData;
+use std::num::{NonZeroU16, NonZeroU32};
 use std::sync::atomic::{AtomicBool, Ordering};
-use std::sync::{mpsc, Arc, Mutex};
+use std::sync::{Arc, Mutex};
 use std::time::{Duration, Instant};
 
 use android_activity::input::{InputEvent, KeyAction, Keycode, MotionAction};
@@ -14,17 +12,21 @@ use android_activity::{
 };
 use tracing::{debug, trace, warn};
 
+use crate::application::ApplicationHandler;
 use crate::cursor::Cursor;
 use crate::dpi::{PhysicalPosition, PhysicalSize, Position, Size};
-use crate::error;
-use crate::error::EventLoopError;
+use crate::error::{self, EventLoopError, ExternalError, NotSupportedError};
 use crate::event::{self, Force, InnerSizeWriter, StartCause};
-use crate::event_loop::{self, ActiveEventLoop as RootAEL, ControlFlow, DeviceEvents};
+use crate::event_loop::{
+    ActiveEventLoop as RootActiveEventLoop, ControlFlow, DeviceEvents,
+    EventLoopProxy as RootEventLoopProxy, OwnedDisplayHandle as RootOwnedDisplayHandle,
+};
+use crate::monitor::MonitorHandle as RootMonitorHandle;
 use crate::platform::pump_events::PumpStatus;
 use crate::platform_impl::Fullscreen;
 use crate::window::{
     self, CursorGrabMode, CustomCursor, CustomCursorSource, ImePurpose, ResizeDirection, Theme,
-    WindowButtons, WindowLevel,
+    Window as RootWindow, WindowAttributes, WindowButtons, WindowLevel,
 };
 
 mod keycodes;
@@ -43,41 +45,6 @@ fn min_timeout(a: Option<Duration>, b: Option<Duration>) -> Option<Duration> {
     a.map_or(b, |a_timeout| b.map_or(Some(a_timeout), |b_timeout| Some(a_timeout.min(b_timeout))))
 }
 
-struct PeekableReceiver<T> {
-    recv: mpsc::Receiver<T>,
-    first: Option<T>,
-}
-
-impl<T> PeekableReceiver<T> {
-    pub fn from_recv(recv: mpsc::Receiver<T>) -> Self {
-        Self { recv, first: None }
-    }
-
-    pub fn has_incoming(&mut self) -> bool {
-        if self.first.is_some() {
-            return true;
-        }
-        match self.recv.try_recv() {
-            Ok(v) => {
-                self.first = Some(v);
-                true
-            },
-            Err(mpsc::TryRecvError::Empty) => false,
-            Err(mpsc::TryRecvError::Disconnected) => {
-                warn!("Channel was disconnected when checking incoming");
-                false
-            },
-        }
-    }
-
-    pub fn try_recv(&mut self) -> Result<T, mpsc::TryRecvError> {
-        if let Some(first) = self.first.take() {
-            return Ok(first);
-        }
-        self.recv.try_recv()
-    }
-}
-
 #[derive(Clone)]
 struct SharedFlagSetter {
     flag: Arc<AtomicBool>,
@@ -133,13 +100,11 @@ impl RedrawRequester {
 #[derive(Debug, Clone, Eq, PartialEq, Hash)]
 pub struct KeyEventExtra {}
 
-pub struct EventLoop<T: 'static> {
-    android_app: AndroidApp,
-    window_target: event_loop::ActiveEventLoop,
+pub struct EventLoop {
+    pub(crate) android_app: AndroidApp,
+    window_target: ActiveEventLoop,
     redraw_flag: SharedFlag,
-    user_events_sender: mpsc::Sender<T>,
-    user_events_receiver: PeekableReceiver<T>, // must wake looper whenever something gets sent
-    loop_running: bool,                        // Dispatched `NewEvents<Init>`
+    loop_running: bool, // Dispatched `NewEvents<Init>`
     running: bool,
     pending_redraw: bool,
     cause: StartCause,
@@ -147,7 +112,7 @@ pub struct EventLoop<T: 'static> {
     combining_accent: Option<char>,
 }
 
-#[derive(Debug, Clone, PartialEq)]
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub(crate) struct PlatformSpecificEventLoopAttributes {
     pub(crate) android_app: Option<AndroidApp>,
     pub(crate) ignore_volume_keys: bool,
@@ -159,11 +124,11 @@ impl Default for PlatformSpecificEventLoopAttributes {
     }
 }
 
-impl<T: 'static> EventLoop<T> {
+impl EventLoop {
     pub(crate) fn new(
         attributes: &PlatformSpecificEventLoopAttributes,
     ) -> Result<Self, EventLoopError> {
-        let (user_events_sender, user_events_receiver) = mpsc::channel();
+        let proxy_wake_up = Arc::new(AtomicBool::new(false));
 
         let android_app = attributes.android_app.as_ref().expect(
             "An `AndroidApp` as passed to android_main() is required to create an `EventLoop` on \
@@ -173,21 +138,14 @@ impl<T: 'static> EventLoop<T> {
 
         Ok(Self {
             android_app: android_app.clone(),
-            window_target: event_loop::ActiveEventLoop {
-                p: ActiveEventLoop {
-                    app: android_app.clone(),
-                    control_flow: Cell::new(ControlFlow::default()),
-                    exit: Cell::new(false),
-                    redraw_requester: RedrawRequester::new(
-                        &redraw_flag,
-                        android_app.create_waker(),
-                    ),
-                },
-                _marker: PhantomData,
+            window_target: ActiveEventLoop {
+                app: android_app.clone(),
+                control_flow: Cell::new(ControlFlow::default()),
+                exit: Cell::new(false),
+                redraw_requester: RedrawRequester::new(&redraw_flag, android_app.create_waker()),
+                proxy_wake_up,
             },
             redraw_flag,
-            user_events_sender,
-            user_events_receiver: PeekableReceiver::from_recv(user_events_receiver),
             loop_running: false,
             running: false,
             pending_redraw: false,
@@ -197,27 +155,32 @@ impl<T: 'static> EventLoop<T> {
         })
     }
 
-    fn single_iteration<F>(&mut self, main_event: Option<MainEvent<'_>>, callback: &mut F)
-    where
-        F: FnMut(event::Event<T>, &RootAEL),
-    {
+    pub(crate) fn window_target(&self) -> &dyn RootActiveEventLoop {
+        &self.window_target
+    }
+
+    fn single_iteration<A: ApplicationHandler>(
+        &mut self,
+        main_event: Option<MainEvent<'_>>,
+        app: &mut A,
+    ) {
         trace!("Mainloop iteration");
 
         let cause = self.cause;
         let mut pending_redraw = self.pending_redraw;
         let mut resized = false;
 
-        callback(event::Event::NewEvents(cause), self.window_target());
+        app.new_events(&self.window_target, cause);
 
         if let Some(event) = main_event {
             trace!("Handling main event {:?}", event);
 
             match event {
                 MainEvent::InitWindow { .. } => {
-                    callback(event::Event::Resumed, self.window_target());
+                    app.can_create_surfaces(&self.window_target);
                 },
                 MainEvent::TerminateWindow { .. } => {
-                    callback(event::Event::Suspended, self.window_target());
+                    app.destroy_surfaces(&self.window_target);
                 },
                 MainEvent::WindowResized { .. } => resized = true,
                 MainEvent::RedrawNeeded { .. } => pending_redraw = true,
@@ -226,46 +189,34 @@ impl<T: 'static> EventLoop<T> {
                 },
                 MainEvent::GainedFocus => {
                     HAS_FOCUS.store(true, Ordering::Relaxed);
-                    callback(
-                        event::Event::WindowEvent {
-                            window_id: window::WindowId(WindowId),
-                            event: event::WindowEvent::Focused(true),
-                        },
-                        self.window_target(),
-                    );
+                    let window_id = window::WindowId(WindowId);
+                    let event = event::WindowEvent::Focused(true);
+                    app.window_event(&self.window_target, window_id, event);
                 },
                 MainEvent::LostFocus => {
                     HAS_FOCUS.store(false, Ordering::Relaxed);
-                    callback(
-                        event::Event::WindowEvent {
-                            window_id: window::WindowId(WindowId),
-                            event: event::WindowEvent::Focused(false),
-                        },
-                        self.window_target(),
-                    );
+                    let window_id = window::WindowId(WindowId);
+                    let event = event::WindowEvent::Focused(false);
+                    app.window_event(&self.window_target, window_id, event);
                 },
                 MainEvent::ConfigChanged { .. } => {
-                    let monitor = MonitorHandle::new(self.android_app.clone());
-                    let old_scale_factor = monitor.scale_factor();
-                    let scale_factor = monitor.scale_factor();
+                    let old_scale_factor = scale_factor(&self.android_app);
+                    let scale_factor = scale_factor(&self.android_app);
                     if (scale_factor - old_scale_factor).abs() < f64::EPSILON {
-                        let new_inner_size = Arc::new(Mutex::new(
-                            MonitorHandle::new(self.android_app.clone()).size(),
-                        ));
-                        let event = event::Event::WindowEvent {
-                            window_id: window::WindowId(WindowId),
-                            event: event::WindowEvent::ScaleFactorChanged {
-                                inner_size_writer: InnerSizeWriter::new(Arc::downgrade(
-                                    &new_inner_size,
-                                )),
-                                scale_factor,
-                            },
+                        let new_inner_size = Arc::new(Mutex::new(screen_size(&self.android_app)));
+                        let window_id = window::WindowId(WindowId);
+                        let event = event::WindowEvent::ScaleFactorChanged {
+                            inner_size_writer: InnerSizeWriter::new(Arc::downgrade(
+                                &new_inner_size,
+                            )),
+                            scale_factor,
                         };
-                        callback(event, self.window_target());
+
+                        app.window_event(&self.window_target, window_id, event);
                     }
                 },
                 MainEvent::LowMemory => {
-                    callback(event::Event::MemoryWarning, self.window_target());
+                    app.memory_warning(&self.window_target);
                 },
                 MainEvent::Start => {
                     // XXX: how to forward this state to applications?
@@ -313,7 +264,7 @@ impl<T: 'static> EventLoop<T> {
         match android_app.input_events_iter() {
             Ok(mut input_iter) => loop {
                 let read_event =
-                    input_iter.next(|event| self.handle_input_event(&android_app, event, callback));
+                    input_iter.next(|event| self.handle_input_event(&android_app, event, app));
 
                 if !read_event {
                     break;
@@ -324,11 +275,8 @@ impl<T: 'static> EventLoop<T> {
             },
         }
 
-        // Empty the user event buffer
-        {
-            while let Ok(event) = self.user_events_receiver.try_recv() {
-                callback(crate::event::Event::UserEvent(event), self.window_target());
-            }
+        if self.window_target.proxy_wake_up.swap(false, Ordering::Relaxed) {
+            app.proxy_wake_up(&self.window_target);
         }
 
         if self.running {
@@ -340,39 +288,32 @@ impl<T: 'static> EventLoop<T> {
                 } else {
                     PhysicalSize::new(0, 0)
                 };
-                let event = event::Event::WindowEvent {
-                    window_id: window::WindowId(WindowId),
-                    event: event::WindowEvent::Resized(size),
-                };
-                callback(event, self.window_target());
+                let window_id = window::WindowId(WindowId);
+                let event = event::WindowEvent::Resized(size);
+                app.window_event(&self.window_target, window_id, event);
             }
 
             pending_redraw |= self.redraw_flag.get_and_reset();
             if pending_redraw {
                 pending_redraw = false;
-                let event = event::Event::WindowEvent {
-                    window_id: window::WindowId(WindowId),
-                    event: event::WindowEvent::RedrawRequested,
-                };
-                callback(event, self.window_target());
+                let window_id = window::WindowId(WindowId);
+                let event = event::WindowEvent::RedrawRequested;
+                app.window_event(&self.window_target, window_id, event);
             }
         }
 
         // This is always the last event we dispatch before poll again
-        callback(event::Event::AboutToWait, self.window_target());
+        app.about_to_wait(&self.window_target);
 
         self.pending_redraw = pending_redraw;
     }
 
-    fn handle_input_event<F>(
+    fn handle_input_event<A: ApplicationHandler>(
         &mut self,
         android_app: &AndroidApp,
         event: &InputEvent<'_>,
-        callback: &mut F,
-    ) -> InputStatus
-    where
-        F: FnMut(event::Event<T>, &RootAEL),
-    {
+        app: &mut A,
+    ) -> InputStatus {
         let mut input_status = InputStatus::Handled;
         match event {
             InputEvent::MotionEvent(motion_event) => {
@@ -410,17 +351,16 @@ impl<T: 'static> EventLoop<T> {
                             "Input event {device_id:?}, {phase:?}, loc={location:?}, \
                              pointer={pointer:?}"
                         );
-                        let event = event::Event::WindowEvent {
-                            window_id,
-                            event: event::WindowEvent::Touch(event::Touch {
-                                device_id,
-                                phase,
-                                location,
-                                id: pointer.pointer_id() as u64,
-                                force: Some(Force::Normalized(pointer.pressure() as f64)),
-                            }),
-                        };
-                        callback(event, self.window_target());
+
+                        let event = event::WindowEvent::Touch(event::Touch {
+                            device_id,
+                            phase,
+                            location,
+                            finger_id: event::FingerId(FingerId(pointer.pointer_id())),
+                            force: Some(Force::Normalized(pointer.pressure() as f64)),
+                        });
+
+                        app.window_event(&self.window_target, window_id, event);
                     }
                 }
             },
@@ -448,23 +388,22 @@ impl<T: 'static> EventLoop<T> {
                             &mut self.combining_accent,
                         );
 
-                        let event = event::Event::WindowEvent {
-                            window_id: window::WindowId(WindowId),
-                            event: event::WindowEvent::KeyboardInput {
-                                device_id: event::DeviceId(DeviceId(key.device_id())),
-                                event: event::KeyEvent {
-                                    state,
-                                    physical_key: keycodes::to_physical_key(keycode),
-                                    logical_key: keycodes::to_logical(key_char, keycode),
-                                    location: keycodes::to_location(keycode),
-                                    repeat: key.repeat_count() > 0,
-                                    text: None,
-                                    platform_specific: KeyEventExtra {},
-                                },
-                                is_synthetic: false,
+                        let window_id = window::WindowId(WindowId);
+                        let event = event::WindowEvent::KeyboardInput {
+                            device_id: event::DeviceId(DeviceId(key.device_id())),
+                            event: event::KeyEvent {
+                                state,
+                                physical_key: keycodes::to_physical_key(keycode),
+                                logical_key: keycodes::to_logical(key_char, keycode),
+                                location: keycodes::to_location(keycode),
+                                repeat: key.repeat_count() > 0,
+                                text: None,
+                                platform_specific: KeyEventExtra {},
                             },
+                            is_synthetic: false,
                         };
-                        callback(event, self.window_target());
+
+                        app.window_event(&self.window_target, window_id, event);
                     },
                 }
             },
@@ -476,19 +415,17 @@ impl<T: 'static> EventLoop<T> {
         input_status
     }
 
-    pub fn run<F>(mut self, event_handler: F) -> Result<(), EventLoopError>
-    where
-        F: FnMut(event::Event<T>, &event_loop::ActiveEventLoop),
-    {
-        self.run_on_demand(event_handler)
+    pub fn run_app<A: ApplicationHandler>(mut self, app: A) -> Result<(), EventLoopError> {
+        self.run_app_on_demand(app)
     }
 
-    pub fn run_on_demand<F>(&mut self, mut event_handler: F) -> Result<(), EventLoopError>
-    where
-        F: FnMut(event::Event<T>, &event_loop::ActiveEventLoop),
-    {
+    pub fn run_app_on_demand<A: ApplicationHandler>(
+        &mut self,
+        mut app: A,
+    ) -> Result<(), EventLoopError> {
+        self.window_target.clear_exit();
         loop {
-            match self.pump_events(None, &mut event_handler) {
+            match self.pump_app_events(None, &mut app) {
                 PumpStatus::Exit(0) => {
                     break Ok(());
                 },
@@ -502,10 +439,11 @@ impl<T: 'static> EventLoop<T> {
         }
     }
 
-    pub fn pump_events<F>(&mut self, timeout: Option<Duration>, mut callback: F) -> PumpStatus
-    where
-        F: FnMut(event::Event<T>, &RootAEL),
-    {
+    pub fn pump_app_events<A: ApplicationHandler>(
+        &mut self,
+        timeout: Option<Duration>,
+        mut app: A,
+    ) -> PumpStatus {
         if !self.loop_running {
             self.loop_running = true;
 
@@ -516,18 +454,18 @@ impl<T: 'static> EventLoop<T> {
             self.cause = StartCause::Init;
 
             // run the initial loop iteration
-            self.single_iteration(None, &mut callback);
+            self.single_iteration(None, &mut app);
         }
 
         // Consider the possibility that the `StartCause::Init` iteration could
         // request to Exit
         if !self.exiting() {
-            self.poll_events_with_timeout(timeout, &mut callback);
+            self.poll_events_with_timeout(timeout, &mut app);
         }
         if self.exiting() {
             self.loop_running = false;
 
-            callback(event::Event::LoopExiting, self.window_target());
+            app.exiting(&self.window_target);
 
             PumpStatus::Exit(0)
         } else {
@@ -535,32 +473,34 @@ impl<T: 'static> EventLoop<T> {
         }
     }
 
-    fn poll_events_with_timeout<F>(&mut self, mut timeout: Option<Duration>, mut callback: F)
-    where
-        F: FnMut(event::Event<T>, &RootAEL),
-    {
+    fn poll_events_with_timeout<A: ApplicationHandler>(
+        &mut self,
+        mut timeout: Option<Duration>,
+        app: &mut A,
+    ) {
         let start = Instant::now();
 
         self.pending_redraw |= self.redraw_flag.get_and_reset();
 
-        timeout =
-            if self.running && (self.pending_redraw || self.user_events_receiver.has_incoming()) {
-                // If we already have work to do then we don't want to block on the next poll
-                Some(Duration::ZERO)
-            } else {
-                let control_flow_timeout = match self.control_flow() {
-                    ControlFlow::Wait => None,
-                    ControlFlow::Poll => Some(Duration::ZERO),
-                    ControlFlow::WaitUntil(wait_deadline) => {
-                        Some(wait_deadline.saturating_duration_since(start))
-                    },
-                };
-
-                min_timeout(control_flow_timeout, timeout)
+        timeout = if self.running
+            && (self.pending_redraw || self.window_target.proxy_wake_up.load(Ordering::Relaxed))
+        {
+            // If we already have work to do then we don't want to block on the next poll
+            Some(Duration::ZERO)
+        } else {
+            let control_flow_timeout = match self.control_flow() {
+                ControlFlow::Wait => None,
+                ControlFlow::Poll => Some(Duration::ZERO),
+                ControlFlow::WaitUntil(wait_deadline) => {
+                    Some(wait_deadline.saturating_duration_since(start))
+                },
             };
 
-        let app = self.android_app.clone(); // Don't borrow self as part of poll expression
-        app.poll_events(timeout, |poll_event| {
+            min_timeout(control_flow_timeout, timeout)
+        };
+
+        let android_app = self.android_app.clone(); // Don't borrow self as part of poll expression
+        android_app.poll_events(timeout, |poll_event| {
             let mut main_event = None;
 
             match poll_event {
@@ -575,7 +515,8 @@ impl<T: 'static> EventLoop<T> {
                     // We also ignore wake ups while suspended.
                     self.pending_redraw |= self.redraw_flag.get_and_reset();
                     if !self.running
-                        || (!self.pending_redraw && !self.user_events_receiver.has_incoming())
+                        || (!self.pending_redraw
+                            && !self.window_target.proxy_wake_up.load(Ordering::Relaxed))
                     {
                         return;
                     }
@@ -601,127 +542,126 @@ impl<T: 'static> EventLoop<T> {
                 },
             };
 
-            self.single_iteration(main_event, &mut callback);
+            self.single_iteration(main_event, app);
         });
     }
 
-    pub fn window_target(&self) -> &event_loop::ActiveEventLoop {
-        &self.window_target
-    }
-
-    pub fn create_proxy(&self) -> EventLoopProxy<T> {
-        EventLoopProxy {
-            user_events_sender: self.user_events_sender.clone(),
-            waker: self.android_app.create_waker(),
-        }
-    }
-
     fn control_flow(&self) -> ControlFlow {
-        self.window_target.p.control_flow()
+        self.window_target.control_flow()
     }
 
     fn exiting(&self) -> bool {
-        self.window_target.p.exiting()
-    }
-}
-
-pub struct EventLoopProxy<T: 'static> {
-    user_events_sender: mpsc::Sender<T>,
-    waker: AndroidAppWaker,
-}
-
-impl<T: 'static> Clone for EventLoopProxy<T> {
-    fn clone(&self) -> Self {
-        EventLoopProxy {
-            user_events_sender: self.user_events_sender.clone(),
-            waker: self.waker.clone(),
-        }
-    }
-}
-
-impl<T> EventLoopProxy<T> {
-    pub fn send_event(&self, event: T) -> Result<(), event_loop::EventLoopClosed<T>> {
-        self.user_events_sender.send(event).map_err(|err| event_loop::EventLoopClosed(err.0))?;
-        self.waker.wake();
-        Ok(())
-    }
-}
-
-pub struct ActiveEventLoop {
-    app: AndroidApp,
-    control_flow: Cell<ControlFlow>,
-    exit: Cell<bool>,
-    redraw_requester: RedrawRequester,
-}
-
-impl ActiveEventLoop {
-    pub fn primary_monitor(&self) -> Option<MonitorHandle> {
-        Some(MonitorHandle::new(self.app.clone()))
-    }
-
-    pub fn create_custom_cursor(&self, source: CustomCursorSource) -> CustomCursor {
-        let _ = source.inner;
-        CustomCursor { inner: PlatformCustomCursor }
-    }
-
-    pub fn available_monitors(&self) -> VecDeque<MonitorHandle> {
-        let mut v = VecDeque::with_capacity(1);
-        v.push_back(MonitorHandle::new(self.app.clone()));
-        v
-    }
-
-    #[inline]
-    pub fn listen_device_events(&self, _allowed: DeviceEvents) {}
-
-    #[cfg(feature = "rwh_05")]
-    #[inline]
-    pub fn raw_display_handle_rwh_05(&self) -> rwh_05::RawDisplayHandle {
-        rwh_05::RawDisplayHandle::Android(rwh_05::AndroidDisplayHandle::empty())
-    }
-
-    #[cfg(feature = "rwh_06")]
-    #[inline]
-    pub fn raw_display_handle_rwh_06(
-        &self,
-    ) -> Result<rwh_06::RawDisplayHandle, rwh_06::HandleError> {
-        Ok(rwh_06::RawDisplayHandle::Android(rwh_06::AndroidDisplayHandle::new()))
-    }
-
-    pub(crate) fn set_control_flow(&self, control_flow: ControlFlow) {
-        self.control_flow.set(control_flow)
-    }
-
-    pub(crate) fn control_flow(&self) -> ControlFlow {
-        self.control_flow.get()
-    }
-
-    pub(crate) fn exit(&self) {
-        self.exit.set(true)
-    }
-
-    pub(crate) fn clear_exit(&self) {
-        self.exit.set(false)
-    }
-
-    pub(crate) fn exiting(&self) -> bool {
-        self.exit.get()
-    }
-
-    pub(crate) fn owned_display_handle(&self) -> OwnedDisplayHandle {
-        OwnedDisplayHandle
+        self.window_target.exiting()
     }
 }
 
 #[derive(Clone)]
+pub struct EventLoopProxy {
+    proxy_wake_up: Arc<AtomicBool>,
+    waker: AndroidAppWaker,
+}
+
+impl EventLoopProxy {
+    pub fn wake_up(&self) {
+        self.proxy_wake_up.store(true, Ordering::Relaxed);
+        self.waker.wake();
+    }
+}
+
+pub struct ActiveEventLoop {
+    pub(crate) app: AndroidApp,
+    control_flow: Cell<ControlFlow>,
+    exit: Cell<bool>,
+    redraw_requester: RedrawRequester,
+    proxy_wake_up: Arc<AtomicBool>,
+}
+
+impl ActiveEventLoop {
+    fn clear_exit(&self) {
+        self.exit.set(false);
+    }
+}
+
+impl RootActiveEventLoop for ActiveEventLoop {
+    fn create_proxy(&self) -> RootEventLoopProxy {
+        let event_loop_proxy = EventLoopProxy {
+            proxy_wake_up: self.proxy_wake_up.clone(),
+            waker: self.app.create_waker(),
+        };
+        RootEventLoopProxy { event_loop_proxy }
+    }
+
+    fn create_window(
+        &self,
+        window_attributes: WindowAttributes,
+    ) -> Result<RootWindow, error::OsError> {
+        let window = Window::new(self, window_attributes)?;
+        Ok(RootWindow { window })
+    }
+
+    fn create_custom_cursor(
+        &self,
+        _source: CustomCursorSource,
+    ) -> Result<CustomCursor, ExternalError> {
+        Err(ExternalError::NotSupported(NotSupportedError::new()))
+    }
+
+    fn available_monitors(&self) -> Box<dyn Iterator<Item = RootMonitorHandle>> {
+        Box::new(std::iter::empty())
+    }
+
+    fn primary_monitor(&self) -> Option<RootMonitorHandle> {
+        None
+    }
+
+    fn system_theme(&self) -> Option<Theme> {
+        None
+    }
+
+    fn listen_device_events(&self, _allowed: DeviceEvents) {}
+
+    fn set_control_flow(&self, control_flow: ControlFlow) {
+        self.control_flow.set(control_flow)
+    }
+
+    fn control_flow(&self) -> ControlFlow {
+        self.control_flow.get()
+    }
+
+    fn exit(&self) {
+        self.exit.set(true)
+    }
+
+    fn exiting(&self) -> bool {
+        self.exit.get()
+    }
+
+    fn owned_display_handle(&self) -> RootOwnedDisplayHandle {
+        RootOwnedDisplayHandle { platform: OwnedDisplayHandle }
+    }
+
+    fn as_any(&self) -> &dyn Any {
+        self
+    }
+
+    #[cfg(feature = "rwh_06")]
+    fn rwh_06_handle(&self) -> &dyn rwh_06::HasDisplayHandle {
+        self
+    }
+}
+
+#[cfg(feature = "rwh_06")]
+impl rwh_06::HasDisplayHandle for ActiveEventLoop {
+    fn display_handle(&self) -> Result<rwh_06::DisplayHandle<'_>, rwh_06::HandleError> {
+        let raw = rwh_06::AndroidDisplayHandle::new();
+        Ok(unsafe { rwh_06::DisplayHandle::borrow_raw(raw.into()) })
+    }
+}
+
+#[derive(Clone, PartialEq, Eq)]
 pub(crate) struct OwnedDisplayHandle;
 
 impl OwnedDisplayHandle {
-    #[cfg(feature = "rwh_05")]
-    #[inline]
-    pub fn raw_display_handle_rwh_05(&self) -> rwh_05::RawDisplayHandle {
-        rwh_05::AndroidDisplayHandle::empty().into()
-    }
-
     #[cfg(feature = "rwh_06")]
     #[inline]
     pub fn raw_display_handle_rwh_06(
@@ -761,6 +701,15 @@ impl DeviceId {
     }
 }
 
+#[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
+pub struct FingerId(i32);
+
+impl FingerId {
+    pub const fn dummy() -> Self {
+        FingerId(0)
+    }
+}
+
 #[derive(Clone, Copy, Debug, Default, Eq, PartialEq)]
 pub struct PlatformSpecificWindowAttributes;
 
@@ -792,21 +741,19 @@ impl Window {
     }
 
     pub fn primary_monitor(&self) -> Option<MonitorHandle> {
-        Some(MonitorHandle::new(self.app.clone()))
+        None
     }
 
-    pub fn available_monitors(&self) -> VecDeque<MonitorHandle> {
-        let mut v = VecDeque::with_capacity(1);
-        v.push_back(MonitorHandle::new(self.app.clone()));
-        v
+    pub fn available_monitors(&self) -> Option<MonitorHandle> {
+        None
     }
 
     pub fn current_monitor(&self) -> Option<MonitorHandle> {
-        Some(MonitorHandle::new(self.app.clone()))
+        None
     }
 
     pub fn scale_factor(&self) -> f64 {
-        MonitorHandle::new(self.app.clone()).scale_factor()
+        scale_factor(&self.app)
     }
 
     pub fn request_redraw(&self) {
@@ -836,7 +783,7 @@ impl Window {
     }
 
     pub fn outer_size(&self) -> PhysicalSize<u32> {
-        MonitorHandle::new(self.app.clone()).size()
+        screen_size(&self.app)
     }
 
     pub fn set_min_inner_size(&self, _: Option<Size>) {}
@@ -943,41 +890,6 @@ impl Window {
         Err(error::ExternalError::NotSupported(error::NotSupportedError::new()))
     }
 
-    #[cfg(feature = "rwh_04")]
-    pub fn raw_window_handle_rwh_04(&self) -> rwh_04::RawWindowHandle {
-        use rwh_04::HasRawWindowHandle;
-
-        if let Some(native_window) = self.app.native_window().as_ref() {
-            native_window.raw_window_handle()
-        } else {
-            panic!(
-                "Cannot get the native window, it's null and will always be null before \
-                 Event::Resumed and after Event::Suspended. Make sure you only call this function \
-                 between those events."
-            );
-        }
-    }
-
-    #[cfg(feature = "rwh_05")]
-    pub fn raw_window_handle_rwh_05(&self) -> rwh_05::RawWindowHandle {
-        use rwh_05::HasRawWindowHandle;
-
-        if let Some(native_window) = self.app.native_window().as_ref() {
-            native_window.raw_window_handle()
-        } else {
-            panic!(
-                "Cannot get the native window, it's null and will always be null before \
-                 Event::Resumed and after Event::Suspended. Make sure you only call this function \
-                 between those events."
-            );
-        }
-    }
-
-    #[cfg(feature = "rwh_05")]
-    pub fn raw_display_handle_rwh_05(&self) -> rwh_05::RawDisplayHandle {
-        rwh_05::RawDisplayHandle::Android(rwh_05::AndroidDisplayHandle::empty())
-    }
-
     #[cfg(feature = "rwh_06")]
     // Allow the usage of HasRawWindowHandle inside this function
     #[allow(deprecated)]
@@ -1040,86 +952,60 @@ impl Display for OsError {
     }
 }
 
-#[derive(Clone, Debug, PartialEq, Eq, Hash)]
-pub struct MonitorHandle {
-    app: AndroidApp,
-}
-impl PartialOrd for MonitorHandle {
-    fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
-        Some(self.cmp(other))
-    }
-}
-impl Ord for MonitorHandle {
-    fn cmp(&self, _other: &Self) -> std::cmp::Ordering {
-        std::cmp::Ordering::Equal
-    }
-}
+#[derive(Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub struct MonitorHandle;
 
 impl MonitorHandle {
-    pub(crate) fn new(app: AndroidApp) -> Self {
-        Self { app }
-    }
-
     pub fn name(&self) -> Option<String> {
-        Some("Android Device".to_owned())
+        unreachable!()
     }
 
-    pub fn size(&self) -> PhysicalSize<u32> {
-        if let Some(native_window) = self.app.native_window() {
-            PhysicalSize::new(native_window.width() as _, native_window.height() as _)
-        } else {
-            PhysicalSize::new(0, 0)
-        }
-    }
-
-    pub fn position(&self) -> PhysicalPosition<i32> {
-        (0, 0).into()
+    pub fn position(&self) -> Option<PhysicalPosition<i32>> {
+        unreachable!()
     }
 
     pub fn scale_factor(&self) -> f64 {
-        self.app.config().density().map(|dpi| dpi as f64 / 160.0).unwrap_or(1.0)
+        unreachable!()
     }
 
-    pub fn refresh_rate_millihertz(&self) -> Option<u32> {
-        // FIXME no way to get real refresh rate for now.
-        None
+    pub fn current_video_mode(&self) -> Option<VideoModeHandle> {
+        unreachable!()
     }
 
-    pub fn video_modes(&self) -> impl Iterator<Item = VideoModeHandle> {
-        let size = self.size().into();
-        // FIXME this is not the real refresh rate
-        // (it is guaranteed to support 32 bit color though)
-        std::iter::once(VideoModeHandle {
-            size,
-            bit_depth: 32,
-            refresh_rate_millihertz: 60000,
-            monitor: self.clone(),
-        })
+    pub fn video_modes(&self) -> std::iter::Empty<VideoModeHandle> {
+        unreachable!()
     }
 }
 
 #[derive(Clone, Debug, Eq, Hash, PartialEq)]
-pub struct VideoModeHandle {
-    size: (u32, u32),
-    bit_depth: u16,
-    refresh_rate_millihertz: u32,
-    monitor: MonitorHandle,
-}
+pub struct VideoModeHandle;
 
 impl VideoModeHandle {
     pub fn size(&self) -> PhysicalSize<u32> {
-        self.size.into()
+        unreachable!()
     }
 
-    pub fn bit_depth(&self) -> u16 {
-        self.bit_depth
+    pub fn bit_depth(&self) -> Option<NonZeroU16> {
+        unreachable!()
     }
 
-    pub fn refresh_rate_millihertz(&self) -> u32 {
-        self.refresh_rate_millihertz
+    pub fn refresh_rate_millihertz(&self) -> Option<NonZeroU32> {
+        unreachable!()
     }
 
     pub fn monitor(&self) -> MonitorHandle {
-        self.monitor.clone()
+        unreachable!()
     }
 }
+
+fn screen_size(app: &AndroidApp) -> PhysicalSize<u32> {
+    if let Some(native_window) = app.native_window() {
+        PhysicalSize::new(native_window.width() as _, native_window.height() as _)
+    } else {
+        PhysicalSize::new(0, 0)
+    }
+}
+
+fn scale_factor(app: &AndroidApp) -> f64 {
+    app.config().density().map(|dpi| dpi as f64 / 160.0).unwrap_or(1.0)
+}

src/platform_impl/apple/appkit/app.rs

@@ -4,8 +4,8 @@ use objc2::{declare_class, msg_send, mutability, ClassType, DeclaredClass};
 use objc2_app_kit::{NSApplication, NSEvent, NSEventModifierFlags, NSEventType, NSResponder};
 use objc2_foundation::{MainThreadMarker, NSObject};
 
-use super::app_delegate::ApplicationDelegate;
-use super::event::flags_contains;
+use super::app_state::ApplicationDelegate;
+use super::DEVICE_ID;
 use crate::event::{DeviceEvent, ElementState};
 
 declare_class!(
@@ -32,7 +32,7 @@ declare_class!(
             let event_type = unsafe { event.r#type() };
             let modifier_flags = unsafe { event.modifierFlags() };
             if event_type == NSEventType::KeyUp
-                && flags_contains(modifier_flags, NSEventModifierFlags::NSEventModifierFlagCommand)
+                && modifier_flags.contains(NSEventModifierFlags::NSEventModifierFlagCommand)
             {
                 if let Some(key_window) = self.keyWindow() {
                     key_window.sendEvent(event);
@@ -57,28 +57,30 @@ fn maybe_dispatch_device_event(delegate: &ApplicationDelegate, event: &NSEvent)
             let delta_x = unsafe { event.deltaX() } as f64;
             let delta_y = unsafe { event.deltaY() } as f64;
 
-            if delta_x != 0.0 {
-                delegate.queue_device_event(DeviceEvent::Motion { axis: 0, value: delta_x });
-            }
-
-            if delta_y != 0.0 {
-                delegate.queue_device_event(DeviceEvent::Motion { axis: 1, value: delta_y })
-            }
-
             if delta_x != 0.0 || delta_y != 0.0 {
-                delegate.queue_device_event(DeviceEvent::MouseMotion { delta: (delta_x, delta_y) });
+                delegate.maybe_queue_with_handler(move |app, event_loop| {
+                    app.device_event(event_loop, DEVICE_ID, DeviceEvent::MouseMotion {
+                        delta: (delta_x, delta_y),
+                    });
+                });
             }
         },
         NSEventType::LeftMouseDown | NSEventType::RightMouseDown | NSEventType::OtherMouseDown => {
-            delegate.queue_device_event(DeviceEvent::Button {
-                button: unsafe { event.buttonNumber() } as u32,
-                state: ElementState::Pressed,
+            let button = unsafe { event.buttonNumber() } as u32;
+            delegate.maybe_queue_with_handler(move |app, event_loop| {
+                app.device_event(event_loop, DEVICE_ID, DeviceEvent::Button {
+                    button,
+                    state: ElementState::Pressed,
+                });
             });
         },
         NSEventType::LeftMouseUp | NSEventType::RightMouseUp | NSEventType::OtherMouseUp => {
-            delegate.queue_device_event(DeviceEvent::Button {
-                button: unsafe { event.buttonNumber() } as u32,
-                state: ElementState::Released,
+            let button = unsafe { event.buttonNumber() } as u32;
+            delegate.maybe_queue_with_handler(move |app, event_loop| {
+                app.device_event(event_loop, DEVICE_ID, DeviceEvent::Button {
+                    button,
+                    state: ElementState::Released,
+                });
             });
         },
         _ => (),

src/platform_impl/apple/appkit/app_state.rs

@@ -1,40 +1,31 @@
 use std::cell::{Cell, RefCell};
-use std::collections::VecDeque;
 use std::mem;
 use std::rc::Weak;
-use std::sync::{Arc, Mutex};
+use std::sync::atomic::{AtomicBool, Ordering as AtomicOrdering};
+use std::sync::Arc;
 use std::time::Instant;
 
-use objc2::rc::Id;
-use objc2::runtime::AnyObject;
+use objc2::rc::Retained;
 use objc2::{declare_class, msg_send_id, mutability, ClassType, DeclaredClass};
 use objc2_app_kit::{NSApplication, NSApplicationActivationPolicy, NSApplicationDelegate};
-use objc2_foundation::{MainThreadMarker, NSObject, NSObjectProtocol, NSSize};
+use objc2_foundation::{MainThreadMarker, NSNotification, NSObject, NSObjectProtocol};
 
 use super::event_handler::EventHandler;
 use super::event_loop::{stop_app_immediately, ActiveEventLoop, PanicInfo};
 use super::observer::{EventLoopWaker, RunLoop};
-use super::window::WinitWindow;
-use super::{menu, WindowId, DEVICE_ID};
-use crate::dpi::PhysicalSize;
-use crate::event::{DeviceEvent, Event, InnerSizeWriter, StartCause, WindowEvent};
-use crate::event_loop::{ActiveEventLoop as RootActiveEventLoop, ControlFlow};
+use super::{menu, WindowId};
+use crate::application::ApplicationHandler;
+use crate::event::{StartCause, WindowEvent};
+use crate::event_loop::ControlFlow;
 use crate::window::WindowId as RootWindowId;
 
 #[derive(Debug)]
-struct Policy(NSApplicationActivationPolicy);
-
-impl Default for Policy {
-    fn default() -> Self {
-        Self(NSApplicationActivationPolicy::Regular)
-    }
-}
-
-#[derive(Debug, Default)]
-pub(super) struct State {
-    activation_policy: Policy,
+pub(super) struct AppState {
+    activation_policy: NSApplicationActivationPolicy,
     default_menu: bool,
     activate_ignoring_other_apps: bool,
+    run_loop: RunLoop,
+    proxy_wake_up: Arc<AtomicBool>,
     event_handler: EventHandler,
     stop_on_launch: Cell<bool>,
     stop_before_wait: Cell<bool>,
@@ -50,8 +41,9 @@ pub(super) struct State {
     waker: RefCell<EventLoopWaker>,
     start_time: Cell<Option<Instant>>,
     wait_timeout: Cell<Option<Instant>>,
-    pending_events: RefCell<VecDeque<QueuedEvent>>,
     pending_redraw: RefCell<Vec<WindowId>>,
+    // NOTE: This is strongly referenced by our `NSWindowDelegate` and our `NSView` subclass, and
+    // as such should be careful to not add fields that, in turn, strongly reference those.
 }
 
 declare_class!(
@@ -65,62 +57,20 @@ declare_class!(
     }
 
     impl DeclaredClass for ApplicationDelegate {
-        type Ivars = State;
+        type Ivars = AppState;
     }
 
     unsafe impl NSObjectProtocol for ApplicationDelegate {}
 
     unsafe impl NSApplicationDelegate for ApplicationDelegate {
-        // Note: This will, globally, only be run once, no matter how many
-        // `EventLoop`s the user creates.
         #[method(applicationDidFinishLaunching:)]
-        fn did_finish_launching(&self, _sender: Option<&AnyObject>) {
-            trace_scope!("applicationDidFinishLaunching:");
-            self.ivars().is_launched.set(true);
-
-            let mtm = MainThreadMarker::from(self);
-            let app = NSApplication::sharedApplication(mtm);
-            // We need to delay setting the activation policy and activating the app
-            // until `applicationDidFinishLaunching` has been called. Otherwise the
-            // menu bar is initially unresponsive on macOS 10.15.
-            app.setActivationPolicy(self.ivars().activation_policy.0);
-
-            window_activation_hack(&app);
-            #[allow(deprecated)]
-            app.activateIgnoringOtherApps(self.ivars().activate_ignoring_other_apps);
-
-            if self.ivars().default_menu {
-                // The menubar initialization should be before the `NewEvents` event, to allow
-                // overriding of the default menu even if it's created
-                menu::initialize(&app);
-            }
-
-            self.ivars().waker.borrow_mut().start();
-
-            self.set_is_running(true);
-            self.dispatch_init_events();
-
-            // If the application is being launched via `EventLoop::pump_app_events()` then we'll
-            // want to stop the app once it is launched (and return to the external loop)
-            //
-            // In this case we still want to consider Winit's `EventLoop` to be "running",
-            // so we call `start_running()` above.
-            if self.ivars().stop_on_launch.get() {
-                // Note: the original idea had been to only stop the underlying `RunLoop`
-                // for the app but that didn't work as expected (`-[NSApplication run]`
-                // effectively ignored the attempt to stop the RunLoop and re-started it).
-                //
-                // So we return from `pump_events` by stopping the application.
-                let app = NSApplication::sharedApplication(mtm);
-                stop_app_immediately(&app);
-            }
+        fn app_did_finish_launching(&self, notification: &NSNotification) {
+            self.did_finish_launching(notification)
         }
 
         #[method(applicationWillTerminate:)]
-        fn will_terminate(&self, _sender: Option<&AnyObject>) {
-            trace_scope!("applicationWillTerminate:");
-            // TODO: Notify every window that it will be destroyed, like done in iOS?
-            self.internal_exit();
+        fn app_will_terminate(&self, notification: &NSNotification) {
+            self.will_terminate(notification)
         }
     }
 );
@@ -131,23 +81,87 @@ impl ApplicationDelegate {
         activation_policy: NSApplicationActivationPolicy,
         default_menu: bool,
         activate_ignoring_other_apps: bool,
-    ) -> Id<Self> {
-        let this = mtm.alloc().set_ivars(State {
-            activation_policy: Policy(activation_policy),
+    ) -> Retained<Self> {
+        let this = mtm.alloc().set_ivars(AppState {
+            activation_policy,
+            proxy_wake_up: Arc::new(AtomicBool::new(false)),
             default_menu,
             activate_ignoring_other_apps,
-            ..Default::default()
+            run_loop: RunLoop::main(mtm),
+            event_handler: EventHandler::new(),
+            stop_on_launch: Cell::new(false),
+            stop_before_wait: Cell::new(false),
+            stop_after_wait: Cell::new(false),
+            stop_on_redraw: Cell::new(false),
+            is_launched: Cell::new(false),
+            is_running: Cell::new(false),
+            exit: Cell::new(false),
+            control_flow: Cell::new(ControlFlow::default()),
+            waker: RefCell::new(EventLoopWaker::new()),
+            start_time: Cell::new(None),
+            wait_timeout: Cell::new(None),
+            pending_redraw: RefCell::new(vec![]),
         });
         unsafe { msg_send_id![super(this), init] }
     }
 
-    pub fn get(mtm: MainThreadMarker) -> Id<Self> {
+    // NOTE: This will, globally, only be run once, no matter how many
+    // `EventLoop`s the user creates.
+    fn did_finish_launching(&self, _notification: &NSNotification) {
+        trace_scope!("applicationDidFinishLaunching:");
+        self.ivars().is_launched.set(true);
+
+        let mtm = MainThreadMarker::from(self);
+        let app = NSApplication::sharedApplication(mtm);
+        // We need to delay setting the activation policy and activating the app
+        // until `applicationDidFinishLaunching` has been called. Otherwise the
+        // menu bar is initially unresponsive on macOS 10.15.
+        app.setActivationPolicy(self.ivars().activation_policy);
+
+        window_activation_hack(&app);
+        #[allow(deprecated)]
+        app.activateIgnoringOtherApps(self.ivars().activate_ignoring_other_apps);
+
+        if self.ivars().default_menu {
+            // The menubar initialization should be before the `NewEvents` event, to allow
+            // overriding of the default menu even if it's created
+            menu::initialize(&app);
+        }
+
+        self.ivars().waker.borrow_mut().start();
+
+        self.set_is_running(true);
+        self.dispatch_init_events();
+
+        // If the application is being launched via `EventLoop::pump_app_events()` then we'll
+        // want to stop the app once it is launched (and return to the external loop)
+        //
+        // In this case we still want to consider Winit's `EventLoop` to be "running",
+        // so we call `start_running()` above.
+        if self.ivars().stop_on_launch.get() {
+            // NOTE: the original idea had been to only stop the underlying `RunLoop`
+            // for the app but that didn't work as expected (`-[NSApplication run]`
+            // effectively ignored the attempt to stop the RunLoop and re-started it).
+            //
+            // So we return from `pump_events` by stopping the application.
+            let app = NSApplication::sharedApplication(mtm);
+            stop_app_immediately(&app);
+        }
+    }
+
+    fn will_terminate(&self, _notification: &NSNotification) {
+        trace_scope!("applicationWillTerminate:");
+        // TODO: Notify every window that it will be destroyed, like done in iOS?
+        self.internal_exit();
+    }
+
+    pub fn get(mtm: MainThreadMarker) -> Retained<Self> {
         let app = NSApplication::sharedApplication(mtm);
         let delegate =
             unsafe { app.delegate() }.expect("a delegate was not configured on the application");
         if delegate.is_kind_of::<Self>() {
             // SAFETY: Just checked that the delegate is an instance of `ApplicationDelegate`
-            unsafe { Id::cast(delegate) }
+            unsafe { Retained::cast(delegate) }
         } else {
             panic!("tried to get a delegate that was not the one Winit has registered")
         }
@@ -157,12 +171,16 @@ impl ApplicationDelegate {
     /// of the given closure.
     pub fn set_event_handler<R>(
         &self,
-        handler: impl FnMut(Event<HandlePendingUserEvents>, &RootActiveEventLoop),
+        handler: &mut dyn ApplicationHandler,
         closure: impl FnOnce() -> R,
     ) -> R {
         self.ivars().event_handler.set(handler, closure)
     }
 
+    pub fn proxy_wake_up(&self) -> Arc<AtomicBool> {
+        self.ivars().proxy_wake_up.clone()
+    }
+
     /// If `pump_events` is called to progress the event loop then we
     /// bootstrap the event loop via `-[NSApplication run]` but will use
     /// `CFRunLoopRunInMode` for subsequent calls to `pump_events`.
@@ -188,10 +206,12 @@ impl ApplicationDelegate {
 
     /// Clears the `running` state and resets the `control_flow` state when an `EventLoop` exits.
     ///
-    /// Note: that if the `NSApplication` has been launched then that state is preserved,
+    /// NOTE: that if the `NSApplication` has been launched then that state is preserved,
     /// and we won't need to re-launch the app if subsequent EventLoops are run.
     pub fn internal_exit(&self) {
-        self.handle_event(Event::LoopExiting);
+        self.with_handler(|app, event_loop| {
+            app.exiting(event_loop);
+        });
 
         self.set_is_running(false);
         self.set_stop_on_redraw(false);
@@ -232,38 +252,13 @@ impl ApplicationDelegate {
         self.ivars().control_flow.get()
     }
 
-    pub fn queue_window_event(&self, window_id: WindowId, event: WindowEvent) {
-        self.ivars()
-            .pending_events
-            .borrow_mut()
-            .push_back(QueuedEvent::WindowEvent(window_id, event));
-    }
-
-    pub fn queue_device_event(&self, event: DeviceEvent) {
-        self.ivars().pending_events.borrow_mut().push_back(QueuedEvent::DeviceEvent(event));
-    }
-
-    pub fn queue_static_scale_factor_changed_event(
-        &self,
-        window: Id<WinitWindow>,
-        suggested_size: PhysicalSize<u32>,
-        scale_factor: f64,
-    ) {
-        self.ivars().pending_events.borrow_mut().push_back(QueuedEvent::ScaleFactorChanged {
-            window,
-            suggested_size,
-            scale_factor,
-        });
-    }
-
     pub fn handle_redraw(&self, window_id: WindowId) {
         let mtm = MainThreadMarker::from(self);
         // Redraw request might come out of order from the OS.
         // -> Don't go back into the event handler when our callstack originates from there
         if !self.ivars().event_handler.in_use() {
-            self.handle_event(Event::WindowEvent {
-                window_id: RootWindowId(window_id),
-                event: WindowEvent::RedrawRequested,
+            self.with_handler(|app, event_loop| {
+                app.window_event(event_loop, RootWindowId(window_id), WindowEvent::RedrawRequested);
             });
 
             // `pump_events` will request to stop immediately _after_ dispatching RedrawRequested
@@ -281,19 +276,44 @@ impl ApplicationDelegate {
         if !pending_redraw.contains(&window_id) {
             pending_redraw.push(window_id);
         }
-        unsafe { RunLoop::get() }.wakeup();
+        self.ivars().run_loop.wakeup();
     }
 
-    fn handle_event(&self, event: Event<HandlePendingUserEvents>) {
-        self.ivars().event_handler.handle_event(event, &ActiveEventLoop::new_root(self.retain()))
+    #[track_caller]
+    pub fn maybe_queue_with_handler(
+        &self,
+        callback: impl FnOnce(&mut dyn ApplicationHandler, &ActiveEventLoop) + 'static,
+    ) {
+        // Most programmer actions in AppKit (e.g. change window fullscreen, set focused, etc.)
+        // result in an event being queued, and applied at a later point.
+        //
+        // However, it is not documented which actions do this, and which ones are done immediately,
+        // so to make sure that we don't encounter re-entrancy issues, we first check if we're
+        // currently handling another event, and if we are, we queue the event instead.
+        if !self.ivars().event_handler.in_use() {
+            self.with_handler(callback);
+        } else {
+            tracing::debug!("had to queue event since another is currently being handled");
+            let this = self.retain();
+            self.ivars().run_loop.queue_closure(move || {
+                this.with_handler(callback);
+            });
+        }
+    }
+
+    #[track_caller]
+    fn with_handler(&self, callback: impl FnOnce(&mut dyn ApplicationHandler, &ActiveEventLoop)) {
+        let event_loop =
+            ActiveEventLoop { delegate: self.retain(), mtm: MainThreadMarker::from(self) };
+        self.ivars().event_handler.handle(callback, &event_loop);
     }
 
     /// dispatch `NewEvents(Init)` + `Resumed`
     pub fn dispatch_init_events(&self) {
-        self.handle_event(Event::NewEvents(StartCause::Init));
-        // NB: For consistency all platforms must emit a 'resumed' event even though macOS
-        // applications don't themselves have a formal suspend/resume lifecycle.
-        self.handle_event(Event::Resumed);
+        self.with_handler(|app, event_loop| app.new_events(event_loop, StartCause::Init));
+        // NB: For consistency all platforms must call `can_create_surfaces` even though macOS
+        // applications don't themselves have a formal surface destroy/create lifecycle.
+        self.with_handler(|app, event_loop| app.can_create_surfaces(event_loop));
     }
 
     // Called by RunLoopObserver after finishing waiting for new events
@@ -326,7 +346,7 @@ impl ApplicationDelegate {
             },
         };
 
-        self.handle_event(Event::NewEvents(cause));
+        self.with_handler(|app, event_loop| app.new_events(event_loop, cause));
     }
 
     // Called by RunLoopObserver before waiting for new events
@@ -343,58 +363,19 @@ impl ApplicationDelegate {
             return;
         }
 
-        self.handle_event(Event::UserEvent(HandlePendingUserEvents));
-
-        let events = mem::take(&mut *self.ivars().pending_events.borrow_mut());
-        for event in events {
-            match event {
-                QueuedEvent::WindowEvent(window_id, event) => {
-                    self.handle_event(Event::WindowEvent {
-                        window_id: RootWindowId(window_id),
-                        event,
-                    });
-                },
-                QueuedEvent::DeviceEvent(event) => {
-                    self.handle_event(Event::DeviceEvent { device_id: DEVICE_ID, event });
-                },
-                QueuedEvent::ScaleFactorChanged { window, suggested_size, scale_factor } => {
-                    let new_inner_size = Arc::new(Mutex::new(suggested_size));
-                    let scale_factor_changed_event = Event::WindowEvent {
-                        window_id: RootWindowId(window.id()),
-                        event: WindowEvent::ScaleFactorChanged {
-                            scale_factor,
-                            inner_size_writer: InnerSizeWriter::new(Arc::downgrade(
-                                &new_inner_size,
-                            )),
-                        },
-                    };
-
-                    self.handle_event(scale_factor_changed_event);
-
-                    let physical_size = *new_inner_size.lock().unwrap();
-                    drop(new_inner_size);
-                    let logical_size = physical_size.to_logical(scale_factor);
-                    let size = NSSize::new(logical_size.width, logical_size.height);
-                    window.setContentSize(size);
-
-                    let resized_event = Event::WindowEvent {
-                        window_id: RootWindowId(window.id()),
-                        event: WindowEvent::Resized(physical_size),
-                    };
-                    self.handle_event(resized_event);
-                },
-            }
+        if self.ivars().proxy_wake_up.swap(false, AtomicOrdering::Relaxed) {
+            self.with_handler(|app, event_loop| app.proxy_wake_up(event_loop));
         }
 
         let redraw = mem::take(&mut *self.ivars().pending_redraw.borrow_mut());
         for window_id in redraw {
-            self.handle_event(Event::WindowEvent {
-                window_id: RootWindowId(window_id),
-                event: WindowEvent::RedrawRequested,
+            self.with_handler(|app, event_loop| {
+                app.window_event(event_loop, RootWindowId(window_id), WindowEvent::RedrawRequested);
             });
         }
-
-        self.handle_event(Event::AboutToWait);
+        self.with_handler(|app, event_loop| {
+            app.about_to_wait(event_loop);
+        });
 
         if self.exiting() {
             let app = NSApplication::sharedApplication(mtm);
@@ -416,20 +397,6 @@ impl ApplicationDelegate {
     }
 }
 
-#[derive(Debug)]
-pub(crate) enum QueuedEvent {
-    WindowEvent(WindowId, WindowEvent),
-    DeviceEvent(DeviceEvent),
-    ScaleFactorChanged {
-        window: Id<WinitWindow>,
-        suggested_size: PhysicalSize<u32>,
-        scale_factor: f64,
-    },
-}
-
-#[derive(Debug)]
-pub(crate) struct HandlePendingUserEvents;
-
 /// Returns the minimum `Option<Instant>`, taking into account that `None`
 /// equates to an infinite timeout, not a zero timeout (so can't just use
 /// `Option::min`)

src/platform_impl/apple/appkit/cursor.rs

@@ -2,7 +2,7 @@ use std::ffi::c_uchar;
 use std::slice;
 use std::sync::OnceLock;
 
-use objc2::rc::Id;
+use objc2::rc::Retained;
 use objc2::runtime::Sel;
 use objc2::{msg_send_id, sel, ClassType};
 use objc2_app_kit::{NSBitmapImageRep, NSCursor, NSDeviceRGBColorSpace, NSImage};
@@ -11,11 +11,13 @@ use objc2_foundation::{
     NSString,
 };
 
+use super::OsError;
 use crate::cursor::{CursorImage, OnlyCursorImageSource};
+use crate::error::ExternalError;
 use crate::window::CursorIcon;
 
 #[derive(Clone, Debug, PartialEq, Eq, Hash)]
-pub struct CustomCursor(pub(crate) Id<NSCursor>);
+pub struct CustomCursor(pub(crate) Retained<NSCursor>);
 
 // SAFETY: NSCursor is immutable and thread-safe
 // TODO(madsmtm): Put this logic in objc2-app-kit itself
@@ -23,12 +25,12 @@ unsafe impl Send for CustomCursor {}
 unsafe impl Sync for CustomCursor {}
 
 impl CustomCursor {
-    pub(crate) fn new(cursor: OnlyCursorImageSource) -> CustomCursor {
-        Self(cursor_from_image(&cursor.0))
+    pub(crate) fn new(cursor: OnlyCursorImageSource) -> Result<CustomCursor, ExternalError> {
+        cursor_from_image(&cursor.0).map(Self)
     }
 }
 
-pub(crate) fn cursor_from_image(cursor: &CursorImage) -> Id<NSCursor> {
+pub(crate) fn cursor_from_image(cursor: &CursorImage) -> Result<Retained<NSCursor>, ExternalError> {
     let width = cursor.width;
     let height = cursor.height;
 
@@ -45,8 +47,8 @@ pub(crate) fn cursor_from_image(cursor: &CursorImage) -> Id<NSCursor> {
             NSDeviceRGBColorSpace,
             width as isize * 4,
             32,
-        ).unwrap()
-    };
+        )
+    }.ok_or_else(|| ExternalError::Os(os_error!(OsError::CreationError("parent view should be installed in a window"))))?;
     let bitmap_data = unsafe { slice::from_raw_parts_mut(bitmap.bitmapData(), cursor.rgba.len()) };
     bitmap_data.copy_from_slice(&cursor.rgba);
 
@@ -57,17 +59,17 @@ pub(crate) fn cursor_from_image(cursor: &CursorImage) -> Id<NSCursor> {
 
     let hotspot = NSPoint::new(cursor.hotspot_x as f64, cursor.hotspot_y as f64);
 
-    NSCursor::initWithImage_hotSpot(NSCursor::alloc(), &image, hotspot)
+    Ok(NSCursor::initWithImage_hotSpot(NSCursor::alloc(), &image, hotspot))
 }
 
-pub(crate) fn default_cursor() -> Id<NSCursor> {
+pub(crate) fn default_cursor() -> Retained<NSCursor> {
     NSCursor::arrowCursor()
 }
 
-unsafe fn try_cursor_from_selector(sel: Sel) -> Option<Id<NSCursor>> {
+unsafe fn try_cursor_from_selector(sel: Sel) -> Option<Retained<NSCursor>> {
     let cls = NSCursor::class();
     if cls.responds_to(sel) {
-        let cursor: Id<NSCursor> = unsafe { msg_send_id![cls, performSelector: sel] };
+        let cursor: Retained<NSCursor> = unsafe { msg_send_id![cls, performSelector: sel] };
         Some(cursor)
     } else {
         tracing::warn!("cursor `{sel}` appears to be invalid");
@@ -82,7 +84,7 @@ macro_rules! def_undocumented_cursor {
     )*} => {$(
         $(#[$($m)*])*
         #[allow(non_snake_case)]
-        fn $name() -> Id<NSCursor> {
+        fn $name() -> Retained<NSCursor> {
             unsafe { try_cursor_from_selector(sel!($name)).unwrap_or_else(|| default_cursor()) }
         }
     )*};
@@ -112,7 +114,7 @@ def_undocumented_cursor!(
 
 // Note that loading `busybutclickable` with this code won't animate
 // the frames; instead you'll just get them all in a column.
-unsafe fn load_webkit_cursor(name: &NSString) -> Id<NSCursor> {
+unsafe fn load_webkit_cursor(name: &NSString) -> Retained<NSCursor> {
     // Snatch a cursor from WebKit; They fit the style of the native
     // cursors, and will seem completely standard to macOS users.
     //
@@ -128,7 +130,7 @@ unsafe fn load_webkit_cursor(name: &NSString) -> Id<NSCursor> {
 
     // TODO: Handle PLists better
     let info_path = cursor_path.stringByAppendingPathComponent(ns_string!("info.plist"));
-    let info: Id<NSDictionary<NSObject, NSObject>> = unsafe {
+    let info: Retained<NSDictionary<NSObject, NSObject>> = unsafe {
         msg_send_id![
             <NSDictionary<NSObject, NSObject>>::class(),
             dictionaryWithContentsOfFile: &*info_path,
@@ -155,15 +157,15 @@ unsafe fn load_webkit_cursor(name: &NSString) -> Id<NSCursor> {
     NSCursor::initWithImage_hotSpot(NSCursor::alloc(), &image, hotspot)
 }
 
-fn webkit_move() -> Id<NSCursor> {
+fn webkit_move() -> Retained<NSCursor> {
     unsafe { load_webkit_cursor(ns_string!("move")) }
 }
 
-fn webkit_cell() -> Id<NSCursor> {
+fn webkit_cell() -> Retained<NSCursor> {
     unsafe { load_webkit_cursor(ns_string!("cell")) }
 }
 
-pub(crate) fn invisible_cursor() -> Id<NSCursor> {
+pub(crate) fn invisible_cursor() -> Retained<NSCursor> {
     // 16x16 GIF data for invisible cursor
     // You can reproduce this via ImageMagick.
     // $ convert -size 16x16 xc:none cursor.gif
@@ -174,7 +176,7 @@ pub(crate) fn invisible_cursor() -> Id<NSCursor> {
         0xa3, 0x9c, 0xb4, 0xda, 0x8b, 0xb3, 0x3e, 0x05, 0x00, 0x3b,
     ];
 
-    fn new_invisible() -> Id<NSCursor> {
+    fn new_invisible() -> Retained<NSCursor> {
         // TODO: Consider using `dataWithBytesNoCopy:`
         let data = NSData::with_bytes(CURSOR_BYTES);
         let image = NSImage::initWithData(NSImage::alloc(), &data).unwrap();
@@ -187,7 +189,7 @@ pub(crate) fn invisible_cursor() -> Id<NSCursor> {
     CURSOR.get_or_init(|| CustomCursor(new_invisible())).0.clone()
 }
 
-pub(crate) fn cursor_from_icon(icon: CursorIcon) -> Id<NSCursor> {
+pub(crate) fn cursor_from_icon(icon: CursorIcon) -> Retained<NSCursor> {
     match icon {
         CursorIcon::Default => default_cursor(),
         CursorIcon::Pointer => NSCursor::pointingHandCursor(),

src/platform_impl/apple/appkit/event.rs

@@ -2,17 +2,17 @@ use std::ffi::c_void;
 
 use core_foundation::base::CFRelease;
 use core_foundation::data::{CFDataGetBytePtr, CFDataRef};
-use objc2::rc::Id;
+use objc2::rc::Retained;
 use objc2_app_kit::{NSEvent, NSEventModifierFlags, NSEventSubtype, NSEventType};
 use objc2_foundation::{run_on_main, NSPoint};
 use smol_str::SmolStr;
 
+use super::ffi;
 use crate::event::{ElementState, KeyEvent, Modifiers};
 use crate::keyboard::{
     Key, KeyCode, KeyLocation, ModifiersKeys, ModifiersState, NamedKey, NativeKey, NativeKeyCode,
     PhysicalKey,
 };
-use crate::platform_impl::platform::ffi;
 
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub struct KeyEventExtra {
@@ -133,8 +133,8 @@ pub(crate) fn create_key_event(
         let key_without_modifiers = get_modifierless_char(scancode);
 
         let modifiers = unsafe { ns_event.modifierFlags() };
-        let has_ctrl = flags_contains(modifiers, NSEventModifierFlags::NSEventModifierFlagControl);
-        let has_cmd = flags_contains(modifiers, NSEventModifierFlags::NSEventModifierFlagCommand);
+        let has_ctrl = modifiers.contains(NSEventModifierFlags::NSEventModifierFlagControl);
+        let has_cmd = modifiers.contains(NSEventModifierFlags::NSEventModifierFlagCommand);
 
         let logical_key = match text_with_all_modifiers.as_ref() {
             // Only checking for ctrl and cmd here, not checking for alt because we DO want to
@@ -305,16 +305,12 @@ const NX_DEVICELALTKEYMASK: NSEventModifierFlags = NSEventModifierFlags(0x000000
 const NX_DEVICERALTKEYMASK: NSEventModifierFlags = NSEventModifierFlags(0x00000040);
 const NX_DEVICERCTLKEYMASK: NSEventModifierFlags = NSEventModifierFlags(0x00002000);
 
-pub(super) fn flags_contains(flags: NSEventModifierFlags, value: NSEventModifierFlags) -> bool {
-    flags.0 & value.0 == value.0
-}
-
 pub(super) fn lalt_pressed(event: &NSEvent) -> bool {
-    flags_contains(unsafe { event.modifierFlags() }, NX_DEVICELALTKEYMASK)
+    unsafe { event.modifierFlags() }.contains(NX_DEVICELALTKEYMASK)
 }
 
 pub(super) fn ralt_pressed(event: &NSEvent) -> bool {
-    flags_contains(unsafe { event.modifierFlags() }, NX_DEVICERALTKEYMASK)
+    unsafe { event.modifierFlags() }.contains(NX_DEVICERALTKEYMASK)
 }
 
 pub(super) fn event_mods(event: &NSEvent) -> Modifiers {
@@ -322,38 +318,33 @@ pub(super) fn event_mods(event: &NSEvent) -> Modifiers {
     let mut state = ModifiersState::empty();
     let mut pressed_mods = ModifiersKeys::empty();
 
-    state.set(
-        ModifiersState::SHIFT,
-        flags_contains(flags, NSEventModifierFlags::NSEventModifierFlagShift),
-    );
-    pressed_mods.set(ModifiersKeys::LSHIFT, flags_contains(flags, NX_DEVICELSHIFTKEYMASK));
-    pressed_mods.set(ModifiersKeys::RSHIFT, flags_contains(flags, NX_DEVICERSHIFTKEYMASK));
+    state
+        .set(ModifiersState::SHIFT, flags.contains(NSEventModifierFlags::NSEventModifierFlagShift));
+    pressed_mods.set(ModifiersKeys::LSHIFT, flags.contains(NX_DEVICELSHIFTKEYMASK));
+    pressed_mods.set(ModifiersKeys::RSHIFT, flags.contains(NX_DEVICERSHIFTKEYMASK));
 
     state.set(
         ModifiersState::CONTROL,
-        flags_contains(flags, NSEventModifierFlags::NSEventModifierFlagControl),
+        flags.contains(NSEventModifierFlags::NSEventModifierFlagControl),
     );
-    pressed_mods.set(ModifiersKeys::LCONTROL, flags_contains(flags, NX_DEVICELCTLKEYMASK));
-    pressed_mods.set(ModifiersKeys::RCONTROL, flags_contains(flags, NX_DEVICERCTLKEYMASK));
+    pressed_mods.set(ModifiersKeys::LCONTROL, flags.contains(NX_DEVICELCTLKEYMASK));
+    pressed_mods.set(ModifiersKeys::RCONTROL, flags.contains(NX_DEVICERCTLKEYMASK));
 
-    state.set(
-        ModifiersState::ALT,
-        flags_contains(flags, NSEventModifierFlags::NSEventModifierFlagOption),
-    );
-    pressed_mods.set(ModifiersKeys::LALT, flags_contains(flags, NX_DEVICELALTKEYMASK));
-    pressed_mods.set(ModifiersKeys::RALT, flags_contains(flags, NX_DEVICERALTKEYMASK));
+    state.set(ModifiersState::ALT, flags.contains(NSEventModifierFlags::NSEventModifierFlagOption));
+    pressed_mods.set(ModifiersKeys::LALT, flags.contains(NX_DEVICELALTKEYMASK));
+    pressed_mods.set(ModifiersKeys::RALT, flags.contains(NX_DEVICERALTKEYMASK));
 
     state.set(
         ModifiersState::SUPER,
-        flags_contains(flags, NSEventModifierFlags::NSEventModifierFlagCommand),
+        flags.contains(NSEventModifierFlags::NSEventModifierFlagCommand),
     );
-    pressed_mods.set(ModifiersKeys::LSUPER, flags_contains(flags, NX_DEVICELCMDKEYMASK));
-    pressed_mods.set(ModifiersKeys::RSUPER, flags_contains(flags, NX_DEVICERCMDKEYMASK));
+    pressed_mods.set(ModifiersKeys::LSUPER, flags.contains(NX_DEVICELCMDKEYMASK));
+    pressed_mods.set(ModifiersKeys::RSUPER, flags.contains(NX_DEVICERCMDKEYMASK));
 
     Modifiers { state, pressed_mods }
 }
 
-pub(super) fn dummy_event() -> Option<Id<NSEvent>> {
+pub(super) fn dummy_event() -> Option<Retained<NSEvent>> {
     unsafe {
         NSEvent::otherEventWithType_location_modifierFlags_timestamp_windowNumber_context_subtype_data1_data2(
             NSEventType::ApplicationDefined,

src/platform_impl/apple/appkit/event_handler.rs

@@ -1,31 +1,34 @@
 use std::cell::RefCell;
 use std::{fmt, mem};
 
-use super::app_delegate::HandlePendingUserEvents;
-use crate::event::Event;
-use crate::event_loop::ActiveEventLoop as RootActiveEventLoop;
+use crate::application::ApplicationHandler;
+use crate::platform_impl::ActiveEventLoop;
 
-struct EventHandlerData {
-    #[allow(clippy::type_complexity)]
-    handler: Box<dyn FnMut(Event<HandlePendingUserEvents>, &RootActiveEventLoop) + 'static>,
-}
-
-impl fmt::Debug for EventHandlerData {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        f.debug_struct("EventHandlerData").finish_non_exhaustive()
-    }
-}
-
-#[derive(Debug, Default)]
+#[derive(Default)]
 pub(crate) struct EventHandler {
     /// This can be in the following states:
     /// - Not registered by the event loop (None).
     /// - Present (Some(handler)).
     /// - Currently executing the handler / in use (RefCell borrowed).
-    inner: RefCell<Option<EventHandlerData>>,
+    inner: RefCell<Option<&'static mut dyn ApplicationHandler>>,
+}
+
+impl fmt::Debug for EventHandler {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let state = match self.inner.try_borrow().as_deref() {
+            Ok(Some(_)) => "<available>",
+            Ok(None) => "<not set>",
+            Err(_) => "<in use>",
+        };
+        f.debug_struct("EventHandler").field("state", &state).finish_non_exhaustive()
+    }
 }
 
 impl EventHandler {
+    pub(crate) fn new() -> Self {
+        Self { inner: RefCell::new(None) }
+    }
+
     /// Set the event loop handler for the duration of the given closure.
     ///
     /// This is similar to using the `scoped-tls` or `scoped-tls-hkt` crates
@@ -33,7 +36,7 @@ impl EventHandler {
     /// from within the closure.
     pub(crate) fn set<'handler, R>(
         &self,
-        handler: impl FnMut(Event<HandlePendingUserEvents>, &RootActiveEventLoop) + 'handler,
+        app: &'handler mut dyn ApplicationHandler,
         closure: impl FnOnce() -> R,
     ) -> R {
         // SAFETY: We extend the lifetime of the handler here so that we can
@@ -44,9 +47,9 @@ impl EventHandler {
         // extended beyond `'handler`.
         let handler = unsafe {
             mem::transmute::<
-                Box<dyn FnMut(Event<HandlePendingUserEvents>, &RootActiveEventLoop) + 'handler>,
-                Box<dyn FnMut(Event<HandlePendingUserEvents>, &RootActiveEventLoop) + 'static>,
-            >(Box::new(handler))
+                &'handler mut dyn ApplicationHandler,
+                &'static mut dyn ApplicationHandler,
+            >(app)
         };
 
         match self.inner.try_borrow_mut().as_deref_mut() {
@@ -54,7 +57,7 @@ impl EventHandler {
                 unreachable!("tried to set handler while another was already set");
             },
             Ok(data @ None) => {
-                *data = Some(EventHandlerData { handler });
+                *data = Some(handler);
             },
             Err(_) => {
                 unreachable!("tried to set handler that is currently in use");
@@ -105,20 +108,20 @@ impl EventHandler {
         matches!(self.inner.try_borrow().as_deref(), Ok(Some(_)))
     }
 
-    pub(crate) fn handle_event(
+    pub(crate) fn handle(
         &self,
-        event: Event<HandlePendingUserEvents>,
-        event_loop: &RootActiveEventLoop,
+        callback: impl FnOnce(&mut dyn ApplicationHandler, &ActiveEventLoop),
+        event_loop: &ActiveEventLoop,
     ) {
         match self.inner.try_borrow_mut().as_deref_mut() {
-            Ok(Some(EventHandlerData { handler })) => {
+            Ok(Some(user_app)) => {
                 // It is important that we keep the reference borrowed here,
                 // so that `in_use` can properly detect that the handler is
                 // still in use.
                 //
                 // If the handler unwinds, the `RefMut` will ensure that the
                 // handler is no longer borrowed.
-                (handler)(event, event_loop);
+                callback(*user_app, event_loop);
             },
             Ok(None) => {
                 // `NSApplication`, our app delegate and this handler are all

src/platform_impl/apple/appkit/event_loop.rs

@@ -1,12 +1,11 @@
 use std::any::Any;
 use std::cell::Cell;
-use std::collections::VecDeque;
-use std::marker::PhantomData;
 use std::os::raw::c_void;
 use std::panic::{catch_unwind, resume_unwind, RefUnwindSafe, UnwindSafe};
 use std::ptr;
 use std::rc::{Rc, Weak};
-use std::sync::mpsc;
+use std::sync::atomic::{AtomicBool, Ordering as AtomicOrdering};
+use std::sync::Arc;
 use std::time::{Duration, Instant};
 
 use core_foundation::base::{CFIndex, CFRelease};
@@ -14,26 +13,31 @@ use core_foundation::runloop::{
     kCFRunLoopCommonModes, CFRunLoopAddSource, CFRunLoopGetMain, CFRunLoopSourceContext,
     CFRunLoopSourceCreate, CFRunLoopSourceRef, CFRunLoopSourceSignal, CFRunLoopWakeUp,
 };
-use objc2::rc::{autoreleasepool, Id};
+use objc2::rc::{autoreleasepool, Retained};
 use objc2::runtime::ProtocolObject;
-use objc2::{msg_send_id, ClassType};
+use objc2::{msg_send_id, sel, ClassType};
 use objc2_app_kit::{NSApplication, NSApplicationActivationPolicy, NSWindow};
 use objc2_foundation::{MainThreadMarker, NSObjectProtocol};
 
 use super::app::WinitApplication;
-use super::app_delegate::{ApplicationDelegate, HandlePendingUserEvents};
+use super::app_state::ApplicationDelegate;
+use super::cursor::CustomCursor;
 use super::event::dummy_event;
-use super::monitor::{self, MonitorHandle};
+use super::monitor;
 use super::observer::setup_control_flow_observers;
-use crate::error::EventLoopError;
-use crate::event::Event;
+use crate::application::ApplicationHandler;
+use crate::error::{EventLoopError, ExternalError};
 use crate::event_loop::{
-    ActiveEventLoop as RootWindowTarget, ControlFlow, DeviceEvents, EventLoopClosed,
+    ActiveEventLoop as RootActiveEventLoop, ControlFlow, DeviceEvents,
+    EventLoopProxy as RootEventLoopProxy, OwnedDisplayHandle as RootOwnedDisplayHandle,
 };
+use crate::monitor::MonitorHandle as RootMonitorHandle;
 use crate::platform::macos::ActivationPolicy;
 use crate::platform::pump_events::PumpStatus;
-use crate::platform_impl::platform::cursor::CustomCursor;
-use crate::window::{CustomCursor as RootCustomCursor, CustomCursorSource};
+use crate::platform_impl::Window;
+use crate::window::{
+    CustomCursor as RootCustomCursor, CustomCursorSource, Theme, Window as RootWindow,
+};
 
 #[derive(Default)]
 pub struct PanicInfo {
@@ -67,75 +71,15 @@ impl PanicInfo {
 
 #[derive(Debug)]
 pub struct ActiveEventLoop {
-    delegate: Id<ApplicationDelegate>,
+    pub(super) delegate: Retained<ApplicationDelegate>,
     pub(super) mtm: MainThreadMarker,
 }
 
 impl ActiveEventLoop {
-    pub(super) fn new_root(delegate: Id<ApplicationDelegate>) -> RootWindowTarget {
-        let mtm = MainThreadMarker::from(&*delegate);
-        let p = Self { delegate, mtm };
-        RootWindowTarget { p, _marker: PhantomData }
+    pub(super) fn app_delegate(&self) -> &ApplicationDelegate {
+        &self.delegate
     }
 
-    pub fn create_custom_cursor(&self, source: CustomCursorSource) -> RootCustomCursor {
-        RootCustomCursor { inner: CustomCursor::new(source.inner) }
-    }
-
-    #[inline]
-    pub fn available_monitors(&self) -> VecDeque<MonitorHandle> {
-        monitor::available_monitors()
-    }
-
-    #[inline]
-    pub fn primary_monitor(&self) -> Option<MonitorHandle> {
-        let monitor = monitor::primary_monitor();
-        Some(monitor)
-    }
-
-    #[inline]
-    pub fn listen_device_events(&self, _allowed: DeviceEvents) {}
-
-    #[cfg(feature = "rwh_05")]
-    #[inline]
-    pub fn raw_display_handle_rwh_05(&self) -> rwh_05::RawDisplayHandle {
-        rwh_05::RawDisplayHandle::AppKit(rwh_05::AppKitDisplayHandle::empty())
-    }
-
-    #[cfg(feature = "rwh_06")]
-    #[inline]
-    pub fn raw_display_handle_rwh_06(
-        &self,
-    ) -> Result<rwh_06::RawDisplayHandle, rwh_06::HandleError> {
-        Ok(rwh_06::RawDisplayHandle::AppKit(rwh_06::AppKitDisplayHandle::new()))
-    }
-
-    pub(crate) fn set_control_flow(&self, control_flow: ControlFlow) {
-        self.delegate.set_control_flow(control_flow)
-    }
-
-    pub(crate) fn control_flow(&self) -> ControlFlow {
-        self.delegate.control_flow()
-    }
-
-    pub(crate) fn exit(&self) {
-        self.delegate.exit()
-    }
-
-    pub(crate) fn clear_exit(&self) {
-        self.delegate.clear_exit()
-    }
-
-    pub(crate) fn exiting(&self) -> bool {
-        self.delegate.exiting()
-    }
-
-    pub(crate) fn owned_display_handle(&self) -> OwnedDisplayHandle {
-        OwnedDisplayHandle
-    }
-}
-
-impl ActiveEventLoop {
     pub(crate) fn hide_application(&self) {
         NSApplication::sharedApplication(self.mtm).hide(None)
     }
@@ -153,37 +97,99 @@ impl ActiveEventLoop {
     }
 }
 
-fn map_user_event<T: 'static>(
-    mut handler: impl FnMut(Event<T>, &RootWindowTarget),
-    receiver: Rc<mpsc::Receiver<T>>,
-) -> impl FnMut(Event<HandlePendingUserEvents>, &RootWindowTarget) {
-    move |event, window_target| match event.map_nonuser_event() {
-        Ok(event) => (handler)(event, window_target),
-        Err(_) => {
-            for event in receiver.try_iter() {
-                (handler)(Event::UserEvent(event), window_target);
-            }
-        },
+impl RootActiveEventLoop for ActiveEventLoop {
+    fn create_proxy(&self) -> RootEventLoopProxy {
+        let event_loop_proxy = EventLoopProxy::new(self.delegate.proxy_wake_up());
+        RootEventLoopProxy { event_loop_proxy }
+    }
+
+    fn create_window(
+        &self,
+        window_attributes: crate::window::WindowAttributes,
+    ) -> Result<crate::window::Window, crate::error::OsError> {
+        let window = Window::new(self, window_attributes)?;
+        Ok(RootWindow { window })
+    }
+
+    fn create_custom_cursor(
+        &self,
+        source: CustomCursorSource,
+    ) -> Result<RootCustomCursor, ExternalError> {
+        Ok(RootCustomCursor { inner: CustomCursor::new(source.inner)? })
+    }
+
+    fn available_monitors(&self) -> Box<dyn Iterator<Item = RootMonitorHandle>> {
+        Box::new(monitor::available_monitors().into_iter().map(|inner| RootMonitorHandle { inner }))
+    }
+
+    fn primary_monitor(&self) -> Option<crate::monitor::MonitorHandle> {
+        let monitor = monitor::primary_monitor();
+        Some(RootMonitorHandle { inner: monitor })
+    }
+
+    fn listen_device_events(&self, _allowed: DeviceEvents) {}
+
+    fn system_theme(&self) -> Option<Theme> {
+        let app = NSApplication::sharedApplication(self.mtm);
+
+        if app.respondsToSelector(sel!(effectiveAppearance)) {
+            Some(super::window_delegate::appearance_to_theme(&app.effectiveAppearance()))
+        } else {
+            Some(Theme::Light)
+        }
+    }
+
+    fn set_control_flow(&self, control_flow: ControlFlow) {
+        self.delegate.set_control_flow(control_flow)
+    }
+
+    fn control_flow(&self) -> ControlFlow {
+        self.delegate.control_flow()
+    }
+
+    fn exit(&self) {
+        self.delegate.exit()
+    }
+
+    fn exiting(&self) -> bool {
+        self.delegate.exiting()
+    }
+
+    fn owned_display_handle(&self) -> RootOwnedDisplayHandle {
+        RootOwnedDisplayHandle { platform: OwnedDisplayHandle }
+    }
+
+    fn as_any(&self) -> &dyn Any {
+        self
+    }
+
+    #[cfg(feature = "rwh_06")]
+    fn rwh_06_handle(&self) -> &dyn rwh_06::HasDisplayHandle {
+        self
     }
 }
 
-pub struct EventLoop<T: 'static> {
+#[cfg(feature = "rwh_06")]
+impl rwh_06::HasDisplayHandle for ActiveEventLoop {
+    fn display_handle(&self) -> Result<rwh_06::DisplayHandle<'_>, rwh_06::HandleError> {
+        let raw = rwh_06::RawDisplayHandle::AppKit(rwh_06::AppKitDisplayHandle::new());
+        unsafe { Ok(rwh_06::DisplayHandle::borrow_raw(raw)) }
+    }
+}
+
+pub struct EventLoop {
     /// Store a reference to the application for convenience.
     ///
     /// We intentionally don't store `WinitApplication` since we want to have
     /// the possibility of swapping that out at some point.
-    app: Id<NSApplication>,
+    app: Retained<NSApplication>,
     /// The application delegate that we've registered.
     ///
     /// The delegate is only weakly referenced by NSApplication, so we must
     /// keep it around here as well.
-    delegate: Id<ApplicationDelegate>,
+    delegate: Retained<ApplicationDelegate>,
 
-    // Event sender and receiver, used for EventLoopProxy.
-    sender: mpsc::Sender<T>,
-    receiver: Rc<mpsc::Receiver<T>>,
-
-    window_target: RootWindowTarget,
+    window_target: ActiveEventLoop,
     panic_info: Rc<PanicInfo>,
 }
 
@@ -204,14 +210,14 @@ impl Default for PlatformSpecificEventLoopAttributes {
     }
 }
 
-impl<T> EventLoop<T> {
+impl EventLoop {
     pub(crate) fn new(
         attributes: &PlatformSpecificEventLoopAttributes,
     ) -> Result<Self, EventLoopError> {
         let mtm = MainThreadMarker::new()
             .expect("on macOS, `EventLoop` must be created on the main thread!");
 
-        let app: Id<NSApplication> =
+        let app: Retained<NSApplication> =
             unsafe { msg_send_id![WinitApplication::class(), sharedApplication] };
 
         if !app.is_kind_of::<WinitApplication>() {
@@ -226,6 +232,7 @@ impl<T> EventLoop<T> {
             ActivationPolicy::Accessory => NSApplicationActivationPolicy::Accessory,
             ActivationPolicy::Prohibited => NSApplicationActivationPolicy::Prohibited,
         };
+
         let delegate = ApplicationDelegate::new(
             mtm,
             activation_policy,
@@ -238,44 +245,34 @@ impl<T> EventLoop<T> {
         });
 
         let panic_info: Rc<PanicInfo> = Default::default();
-        setup_control_flow_observers(Rc::downgrade(&panic_info));
+        setup_control_flow_observers(mtm, Rc::downgrade(&panic_info));
 
-        let (sender, receiver) = mpsc::channel();
         Ok(EventLoop {
             app,
             delegate: delegate.clone(),
-            sender,
-            receiver: Rc::new(receiver),
-            window_target: RootWindowTarget {
-                p: ActiveEventLoop { delegate, mtm },
-                _marker: PhantomData,
-            },
+            window_target: ActiveEventLoop { delegate, mtm },
             panic_info,
         })
     }
 
-    pub fn window_target(&self) -> &RootWindowTarget {
+    pub fn window_target(&self) -> &dyn RootActiveEventLoop {
         &self.window_target
     }
 
-    pub fn run<F>(mut self, handler: F) -> Result<(), EventLoopError>
-    where
-        F: FnMut(Event<T>, &RootWindowTarget),
-    {
-        self.run_on_demand(handler)
+    pub fn run_app<A: ApplicationHandler>(mut self, app: A) -> Result<(), EventLoopError> {
+        self.run_app_on_demand(app)
     }
 
     // NB: we don't base this on `pump_events` because for `MacOs` we can't support
     // `pump_events` elegantly (we just ask to run the loop for a "short" amount of
     // time and so a layered implementation would end up using a lot of CPU due to
     // redundant wake ups.
-    pub fn run_on_demand<F>(&mut self, handler: F) -> Result<(), EventLoopError>
-    where
-        F: FnMut(Event<T>, &RootWindowTarget),
-    {
-        let handler = map_user_event(handler, self.receiver.clone());
-
-        self.delegate.set_event_handler(handler, || {
+    pub fn run_app_on_demand<A: ApplicationHandler>(
+        &mut self,
+        mut app: A,
+    ) -> Result<(), EventLoopError> {
+        self.delegate.clear_exit();
+        self.delegate.set_event_handler(&mut app, || {
             autoreleasepool(|_| {
                 // clear / normalize pump_events state
                 self.delegate.set_wait_timeout(None);
@@ -308,13 +305,12 @@ impl<T> EventLoop<T> {
         Ok(())
     }
 
-    pub fn pump_events<F>(&mut self, timeout: Option<Duration>, handler: F) -> PumpStatus
-    where
-        F: FnMut(Event<T>, &RootWindowTarget),
-    {
-        let handler = map_user_event(handler, self.receiver.clone());
-
-        self.delegate.set_event_handler(handler, || {
+    pub fn pump_app_events<A: ApplicationHandler>(
+        &mut self,
+        timeout: Option<Duration>,
+        mut app: A,
+    ) -> PumpStatus {
+        self.delegate.set_event_handler(&mut app, || {
             autoreleasepool(|_| {
                 // As a special case, if the application hasn't been launched yet then we at least
                 // run the loop until it has fully launched.
@@ -377,22 +373,12 @@ impl<T> EventLoop<T> {
             })
         })
     }
-
-    pub fn create_proxy(&self) -> EventLoopProxy<T> {
-        EventLoopProxy::new(self.sender.clone())
-    }
 }
 
-#[derive(Clone)]
+#[derive(Clone, PartialEq, Eq)]
 pub(crate) struct OwnedDisplayHandle;
 
 impl OwnedDisplayHandle {
-    #[cfg(feature = "rwh_05")]
-    #[inline]
-    pub fn raw_display_handle_rwh_05(&self) -> rwh_05::RawDisplayHandle {
-        rwh_05::AppKitDisplayHandle::empty().into()
-    }
-
     #[cfg(feature = "rwh_06")]
     #[inline]
     pub fn raw_display_handle_rwh_06(
@@ -437,15 +423,15 @@ pub fn stop_app_on_panic<F: FnOnce() -> R + UnwindSafe, R>(
     }
 }
 
-pub struct EventLoopProxy<T> {
-    sender: mpsc::Sender<T>,
+pub struct EventLoopProxy {
+    proxy_wake_up: Arc<AtomicBool>,
     source: CFRunLoopSourceRef,
 }
 
-unsafe impl<T: Send> Send for EventLoopProxy<T> {}
-unsafe impl<T: Send> Sync for EventLoopProxy<T> {}
+unsafe impl Send for EventLoopProxy {}
+unsafe impl Sync for EventLoopProxy {}
 
-impl<T> Drop for EventLoopProxy<T> {
+impl Drop for EventLoopProxy {
     fn drop(&mut self) {
         unsafe {
             CFRelease(self.source as _);
@@ -453,14 +439,14 @@ impl<T> Drop for EventLoopProxy<T> {
     }
 }
 
-impl<T> Clone for EventLoopProxy<T> {
+impl Clone for EventLoopProxy {
     fn clone(&self) -> Self {
-        EventLoopProxy::new(self.sender.clone())
+        EventLoopProxy::new(self.proxy_wake_up.clone())
     }
 }
 
-impl<T> EventLoopProxy<T> {
-    fn new(sender: mpsc::Sender<T>) -> Self {
+impl EventLoopProxy {
+    fn new(proxy_wake_up: Arc<AtomicBool>) -> Self {
         unsafe {
             // just wake up the eventloop
             extern "C" fn event_loop_proxy_handler(_: *const c_void) {}
@@ -480,23 +466,21 @@ impl<T> EventLoopProxy<T> {
                 cancel: None,
                 perform: event_loop_proxy_handler,
             };
-            let source =
-                CFRunLoopSourceCreate(ptr::null_mut(), CFIndex::max_value() - 1, &mut context);
+            let source = CFRunLoopSourceCreate(ptr::null_mut(), CFIndex::MAX - 1, &mut context);
             CFRunLoopAddSource(rl, source, kCFRunLoopCommonModes);
             CFRunLoopWakeUp(rl);
 
-            EventLoopProxy { sender, source }
+            EventLoopProxy { proxy_wake_up, source }
         }
     }
 
-    pub fn send_event(&self, event: T) -> Result<(), EventLoopClosed<T>> {
-        self.sender.send(event).map_err(|mpsc::SendError(x)| EventLoopClosed(x))?;
+    pub fn wake_up(&self) {
+        self.proxy_wake_up.store(true, AtomicOrdering::Relaxed);
         unsafe {
             // let the main thread know there's a new event
             CFRunLoopSourceSignal(self.source);
             let rl = CFRunLoopGetMain();
             CFRunLoopWakeUp(rl);
         }
-        Ok(())
     }
 }

src/platform_impl/apple/appkit/menu.rs

@@ -1,4 +1,4 @@
-use objc2::rc::Id;
+use objc2::rc::Retained;
 use objc2::runtime::Sel;
 use objc2::sel;
 use objc2_app_kit::{NSApplication, NSEventModifierFlags, NSMenu, NSMenuItem};
@@ -48,10 +48,10 @@ pub fn initialize(app: &NSApplication) {
         Some(sel!(hideOtherApplications:)),
         Some(KeyEquivalent {
             key: ns_string!("h"),
-            masks: Some(NSEventModifierFlags(
-                NSEventModifierFlags::NSEventModifierFlagOption.0
-                    | NSEventModifierFlags::NSEventModifierFlagCommand.0,
-            )),
+            masks: Some(
+                NSEventModifierFlags::NSEventModifierFlagOption
+                    | NSEventModifierFlags::NSEventModifierFlagCommand,
+            ),
         }),
     );
 
@@ -91,7 +91,7 @@ fn menu_item(
     title: &NSString,
     selector: Option<Sel>,
     key_equivalent: Option<KeyEquivalent<'_>>,
-) -> Id<NSMenuItem> {
+) -> Retained<NSMenuItem> {
     let (key, masks) = match key_equivalent {
         Some(ke) => (ke.key, ke.masks),
         None => (ns_string!(""), None),

src/platform_impl/apple/appkit/mod.rs

@@ -2,7 +2,7 @@
 mod util;
 
 mod app;
-mod app_delegate;
+mod app_state;
 mod cursor;
 mod event;
 mod event_handler;
@@ -17,19 +17,17 @@ mod window_delegate;
 
 use std::fmt;
 
+pub(crate) use self::cursor::CustomCursor as PlatformCustomCursor;
 pub(crate) use self::event::{physicalkey_to_scancode, scancode_to_physicalkey, KeyEventExtra};
 pub(crate) use self::event_loop::{
     ActiveEventLoop, EventLoop, EventLoopProxy, OwnedDisplayHandle,
     PlatformSpecificEventLoopAttributes,
 };
 pub(crate) use self::monitor::{MonitorHandle, VideoModeHandle};
-pub(crate) use self::window::WindowId;
+pub(crate) use self::window::{Window, WindowId};
 pub(crate) use self::window_delegate::PlatformSpecificWindowAttributes;
-use crate::event::DeviceId as RootDeviceId;
-
-pub(crate) use self::cursor::CustomCursor as PlatformCustomCursor;
-pub(crate) use self::window::Window;
 pub(crate) use crate::cursor::OnlyCursorImageSource as PlatformCustomCursorSource;
+use crate::event::DeviceId as RootDeviceId;
 pub(crate) use crate::icon::NoIcon as PlatformIcon;
 pub(crate) use crate::platform_impl::Fullscreen;
 
@@ -37,7 +35,7 @@ pub(crate) use crate::platform_impl::Fullscreen;
 pub struct DeviceId;
 
 impl DeviceId {
-    pub const unsafe fn dummy() -> Self {
+    pub const fn dummy() -> Self {
         DeviceId
     }
 }
@@ -45,6 +43,15 @@ impl DeviceId {
 // Constant device ID; to be removed when if backend is updated to report real device IDs.
 pub(crate) const DEVICE_ID: RootDeviceId = RootDeviceId(DeviceId);
 
+#[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub struct FingerId;
+
+impl FingerId {
+    pub const fn dummy() -> Self {
+        FingerId
+    }
+}
+
 #[derive(Debug)]
 pub enum OsError {
     CGError(core_graphics::base::CGError),

src/platform_impl/apple/appkit/monitor.rs

@@ -2,6 +2,7 @@
 
 use std::collections::VecDeque;
 use std::fmt;
+use std::num::{NonZeroU16, NonZeroU32};
 
 use core_foundation::array::{CFArrayGetCount, CFArrayGetValueAtIndex};
 use core_foundation::base::{CFRelease, TCFType};
@@ -9,7 +10,7 @@ use core_foundation::string::CFString;
 use core_graphics::display::{
     CGDirectDisplayID, CGDisplay, CGDisplayBounds, CGDisplayCopyDisplayMode,
 };
-use objc2::rc::Id;
+use objc2::rc::Retained;
 use objc2::runtime::AnyObject;
 use objc2_app_kit::NSScreen;
 use objc2_foundation::{ns_string, run_on_main, MainThreadMarker, NSNumber, NSPoint, NSRect};
@@ -20,8 +21,8 @@ use crate::dpi::{LogicalPosition, PhysicalPosition, PhysicalSize};
 #[derive(Clone)]
 pub struct VideoModeHandle {
     size: PhysicalSize<u32>,
-    bit_depth: u16,
-    refresh_rate_millihertz: u32,
+    bit_depth: Option<NonZeroU16>,
+    refresh_rate_millihertz: Option<NonZeroU32>,
     pub(crate) monitor: MonitorHandle,
     pub(crate) native_mode: NativeDisplayMode,
 }
@@ -80,15 +81,47 @@ impl Clone for NativeDisplayMode {
 }
 
 impl VideoModeHandle {
+    fn new(
+        monitor: MonitorHandle,
+        mode: NativeDisplayMode,
+        refresh_rate_millihertz: Option<NonZeroU32>,
+    ) -> Self {
+        unsafe {
+            let pixel_encoding =
+                CFString::wrap_under_create_rule(ffi::CGDisplayModeCopyPixelEncoding(mode.0))
+                    .to_string();
+            let bit_depth = if pixel_encoding.eq_ignore_ascii_case(ffi::IO32BitDirectPixels) {
+                32
+            } else if pixel_encoding.eq_ignore_ascii_case(ffi::IO16BitDirectPixels) {
+                16
+            } else if pixel_encoding.eq_ignore_ascii_case(ffi::kIO30BitDirectPixels) {
+                30
+            } else {
+                unimplemented!()
+            };
+
+            VideoModeHandle {
+                size: PhysicalSize::new(
+                    ffi::CGDisplayModeGetPixelWidth(mode.0) as u32,
+                    ffi::CGDisplayModeGetPixelHeight(mode.0) as u32,
+                ),
+                refresh_rate_millihertz,
+                bit_depth: NonZeroU16::new(bit_depth),
+                monitor: monitor.clone(),
+                native_mode: mode,
+            }
+        }
+    }
+
     pub fn size(&self) -> PhysicalSize<u32> {
         self.size
     }
 
-    pub fn bit_depth(&self) -> u16 {
+    pub fn bit_depth(&self) -> Option<NonZeroU16> {
         self.bit_depth
     }
 
-    pub fn refresh_rate_millihertz(&self) -> u32 {
+    pub fn refresh_rate_millihertz(&self) -> Option<NonZeroU32> {
         self.refresh_rate_millihertz
     }
 
@@ -158,10 +191,8 @@ impl fmt::Debug for MonitorHandle {
         f.debug_struct("MonitorHandle")
             .field("name", &self.name())
             .field("native_identifier", &self.native_identifier())
-            .field("size", &self.size())
             .field("position", &self.position())
             .field("scale_factor", &self.scale_factor())
-            .field("refresh_rate_millihertz", &self.refresh_rate_millihertz())
             .finish_non_exhaustive()
     }
 }
@@ -184,22 +215,14 @@ impl MonitorHandle {
         self.0
     }
 
-    pub fn size(&self) -> PhysicalSize<u32> {
-        let MonitorHandle(display_id) = *self;
-        let display = CGDisplay::new(display_id);
-        let height = display.pixels_high();
-        let width = display.pixels_wide();
-        PhysicalSize::from_logical::<_, f64>((width as f64, height as f64), self.scale_factor())
-    }
-
     #[inline]
-    pub fn position(&self) -> PhysicalPosition<i32> {
+    pub fn position(&self) -> Option<PhysicalPosition<i32>> {
         // This is already in screen coordinates. If we were using `NSScreen`,
         // then a conversion would've been needed:
         // flip_window_screen_coordinates(self.ns_screen(mtm)?.frame())
         let bounds = unsafe { CGDisplayBounds(self.native_identifier()) };
         let position = LogicalPosition::new(bounds.origin.x, bounds.origin.y);
-        position.to_physical(self.scale_factor())
+        Some(position.to_physical(self.scale_factor()))
     }
 
     pub fn scale_factor(&self) -> f64 {
@@ -211,34 +234,20 @@ impl MonitorHandle {
         })
     }
 
-    pub fn refresh_rate_millihertz(&self) -> Option<u32> {
-        unsafe {
-            let current_display_mode = NativeDisplayMode(CGDisplayCopyDisplayMode(self.0) as _);
-            let refresh_rate = ffi::CGDisplayModeGetRefreshRate(current_display_mode.0);
-            if refresh_rate > 0.0 {
-                return Some((refresh_rate * 1000.0).round() as u32);
-            }
+    fn refresh_rate_millihertz(&self) -> Option<NonZeroU32> {
+        let current_display_mode =
+            NativeDisplayMode(unsafe { CGDisplayCopyDisplayMode(self.0) } as _);
+        refresh_rate_millihertz(self.0, &current_display_mode)
+    }
 
-            let mut display_link = std::ptr::null_mut();
-            if ffi::CVDisplayLinkCreateWithCGDisplay(self.0, &mut display_link)
-                != ffi::kCVReturnSuccess
-            {
-                return None;
-            }
-            let time = ffi::CVDisplayLinkGetNominalOutputVideoRefreshPeriod(display_link);
-            ffi::CVDisplayLinkRelease(display_link);
-
-            // This value is indefinite if an invalid display link was specified
-            if time.flags & ffi::kCVTimeIsIndefinite != 0 {
-                return None;
-            }
-
-            (time.time_scale as i64).checked_div(time.time_value).map(|v| (v * 1000) as u32)
-        }
+    pub fn current_video_mode(&self) -> Option<VideoModeHandle> {
+        let mode = NativeDisplayMode(unsafe { CGDisplayCopyDisplayMode(self.0) } as _);
+        let refresh_rate_millihertz = refresh_rate_millihertz(self.0, &mode);
+        Some(VideoModeHandle::new(self.clone(), mode, refresh_rate_millihertz))
     }
 
     pub fn video_modes(&self) -> impl Iterator<Item = VideoModeHandle> {
-        let refresh_rate_millihertz = self.refresh_rate_millihertz().unwrap_or(0);
+        let refresh_rate_millihertz = self.refresh_rate_millihertz();
         let monitor = self.clone();
 
         unsafe {
@@ -263,39 +272,21 @@ impl MonitorHandle {
                 // CGDisplayModeGetRefreshRate returns 0.0 for any display that
                 // isn't a CRT
                 let refresh_rate_millihertz = if cg_refresh_rate_hertz > 0 {
-                    (cg_refresh_rate_hertz * 1000) as u32
+                    NonZeroU32::new((cg_refresh_rate_hertz * 1000) as u32)
                 } else {
                     refresh_rate_millihertz
                 };
 
-                let pixel_encoding =
-                    CFString::wrap_under_create_rule(ffi::CGDisplayModeCopyPixelEncoding(mode))
-                        .to_string();
-                let bit_depth = if pixel_encoding.eq_ignore_ascii_case(ffi::IO32BitDirectPixels) {
-                    32
-                } else if pixel_encoding.eq_ignore_ascii_case(ffi::IO16BitDirectPixels) {
-                    16
-                } else if pixel_encoding.eq_ignore_ascii_case(ffi::kIO30BitDirectPixels) {
-                    30
-                } else {
-                    unimplemented!()
-                };
-
-                VideoModeHandle {
-                    size: PhysicalSize::new(
-                        ffi::CGDisplayModeGetPixelWidth(mode) as u32,
-                        ffi::CGDisplayModeGetPixelHeight(mode) as u32,
-                    ),
+                VideoModeHandle::new(
+                    monitor.clone(),
+                    NativeDisplayMode(mode),
                     refresh_rate_millihertz,
-                    bit_depth,
-                    monitor: monitor.clone(),
-                    native_mode: NativeDisplayMode(mode),
-                }
+                )
             })
         }
     }
 
-    pub(crate) fn ns_screen(&self, mtm: MainThreadMarker) -> Option<Id<NSScreen>> {
+    pub(crate) fn ns_screen(&self, mtm: MainThreadMarker) -> Option<Retained<NSScreen>> {
         let uuid = unsafe { ffi::CGDisplayCreateUUIDFromDisplayID(self.0) };
         NSScreen::screens(mtm).into_iter().find(|screen| {
             let other_native_id = get_display_id(screen);
@@ -349,3 +340,29 @@ pub(crate) fn flip_window_screen_coordinates(frame: NSRect) -> NSPoint {
     let y = main_screen_height - frame.size.height - frame.origin.y;
     NSPoint::new(frame.origin.x, y)
 }
+
+fn refresh_rate_millihertz(id: CGDirectDisplayID, mode: &NativeDisplayMode) -> Option<NonZeroU32> {
+    unsafe {
+        let refresh_rate = ffi::CGDisplayModeGetRefreshRate(mode.0);
+        if refresh_rate > 0.0 {
+            return NonZeroU32::new((refresh_rate * 1000.0).round() as u32);
+        }
+
+        let mut display_link = std::ptr::null_mut();
+        if ffi::CVDisplayLinkCreateWithCGDisplay(id, &mut display_link) != ffi::kCVReturnSuccess {
+            return None;
+        }
+        let time = ffi::CVDisplayLinkGetNominalOutputVideoRefreshPeriod(display_link);
+        ffi::CVDisplayLinkRelease(display_link);
+
+        // This value is indefinite if an invalid display link was specified
+        if time.flags & ffi::kCVTimeIsIndefinite != 0 {
+            return None;
+        }
+
+        (time.time_scale as i64)
+            .checked_div(time.time_value)
+            .map(|v| (v * 1000) as u32)
+            .and_then(NonZeroU32::new)
+    }
+}

src/platform_impl/apple/appkit/observer.rs

@@ -1,21 +1,28 @@
+//! Utilities for working with `CFRunLoop`.
+//!
+//! See Apple's documentation on Run Loops for details:
+//! <https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/Multithreading/RunLoopManagement/RunLoopManagement.html>
+use std::cell::Cell;
 use std::ffi::c_void;
 use std::panic::{AssertUnwindSafe, UnwindSafe};
 use std::ptr;
 use std::rc::Weak;
 use std::time::Instant;
 
-use core_foundation::base::{CFIndex, CFOptionFlags, CFRelease};
+use block2::Block;
+use core_foundation::base::{CFIndex, CFOptionFlags, CFRelease, CFTypeRef};
 use core_foundation::date::CFAbsoluteTimeGetCurrent;
 use core_foundation::runloop::{
-    kCFRunLoopAfterWaiting, kCFRunLoopBeforeWaiting, kCFRunLoopCommonModes, kCFRunLoopExit,
-    CFRunLoopActivity, CFRunLoopAddObserver, CFRunLoopAddTimer, CFRunLoopGetMain,
+    kCFRunLoopAfterWaiting, kCFRunLoopBeforeWaiting, kCFRunLoopCommonModes, kCFRunLoopDefaultMode,
+    kCFRunLoopExit, CFRunLoopActivity, CFRunLoopAddObserver, CFRunLoopAddTimer, CFRunLoopGetMain,
     CFRunLoopObserverCallBack, CFRunLoopObserverContext, CFRunLoopObserverCreate,
     CFRunLoopObserverRef, CFRunLoopRef, CFRunLoopTimerCreate, CFRunLoopTimerInvalidate,
     CFRunLoopTimerRef, CFRunLoopTimerSetNextFireDate, CFRunLoopWakeUp,
 };
 use objc2_foundation::MainThreadMarker;
+use tracing::error;
 
-use super::app_delegate::ApplicationDelegate;
+use super::app_state::ApplicationDelegate;
 use super::event_loop::{stop_app_on_panic, PanicInfo};
 use super::ffi;
 
@@ -84,10 +91,20 @@ extern "C" fn control_flow_end_handler(
     }
 }
 
+#[derive(Debug)]
 pub struct RunLoop(CFRunLoopRef);
 
+impl Default for RunLoop {
+    fn default() -> Self {
+        Self(ptr::null_mut())
+    }
+}
+
 impl RunLoop {
-    pub unsafe fn get() -> Self {
+    pub fn main(mtm: MainThreadMarker) -> Self {
+        // SAFETY: We have a MainThreadMarker here, which means we know we're on the main thread, so
+        // scheduling (and scheduling a non-`Send` block) to that thread is allowed.
+        let _ = mtm;
         RunLoop(unsafe { CFRunLoopGetMain() })
     }
 
@@ -114,9 +131,79 @@ impl RunLoop {
         };
         unsafe { CFRunLoopAddObserver(self.0, observer, kCFRunLoopCommonModes) };
     }
+
+    /// Submit a closure to run on the main thread as the next step in the run loop, before other
+    /// event sources are processed.
+    ///
+    /// This is used for running event handlers, as those are not allowed to run re-entrantly.
+    ///
+    /// # Implementation
+    ///
+    /// This queuing could be implemented in the following several ways with subtle differences in
+    /// timing. This list is sorted in rough order in which they are run:
+    ///
+    /// 1. Using `CFRunLoopPerformBlock` or `-[NSRunLoop performBlock:]`.
+    ///
+    /// 2. Using `-[NSObject performSelectorOnMainThread:withObject:waitUntilDone:]` or wrapping the
+    ///    event in `NSEvent` and posting that to `-[NSApplication postEvent:atStart:]` (both
+    ///    creates a custom `CFRunLoopSource`, and signals that to wake up the main event loop).
+    ///
+    ///    a. `atStart = true`.
+    ///
+    ///    b. `atStart = false`.
+    ///
+    /// 3. `dispatch_async` or `dispatch_async_f`. Note that this may appear before 2b, it does not
+    ///    respect the ordering that runloop events have.
+    ///
+    /// We choose the first one, both for ease-of-implementation, but mostly for consistency, as we
+    /// want the event to be queued in a way that preserves the order the events originally arrived
+    /// in.
+    ///
+    /// As an example, let's assume that we receive two events from the user, a mouse click which we
+    /// handled by queuing it, and a window resize which we handled immediately. If we allowed
+    /// AppKit to choose the ordering when queuing the mouse event, it might get put in the back of
+    /// the queue, and the events would appear out of order to the user of Winit. So we must instead
+    /// put the event at the very front of the queue, to be handled as soon as possible after
+    /// handling whatever event it's currently handling.
+    pub fn queue_closure(&self, closure: impl FnOnce() + 'static) {
+        extern "C" {
+            fn CFRunLoopPerformBlock(rl: CFRunLoopRef, mode: CFTypeRef, block: &Block<dyn Fn()>);
+        }
+
+        // Convert `FnOnce()` to `Block<dyn Fn()>`.
+        let closure = Cell::new(Some(closure));
+        let block = block2::RcBlock::new(move || {
+            if let Some(closure) = closure.take() {
+                closure()
+            } else {
+                error!("tried to execute queued closure on main thread twice");
+            }
+        });
+
+        // There are a few common modes (`kCFRunLoopCommonModes`) defined by Cocoa:
+        // - `NSDefaultRunLoopMode`, alias of `kCFRunLoopDefaultMode`.
+        // - `NSEventTrackingRunLoopMode`, used when mouse-dragging and live-resizing a window.
+        // - `NSModalPanelRunLoopMode`, used when running a modal inside the Winit event loop.
+        // - `NSConnectionReplyMode`: TODO.
+        //
+        // We only want to run event handlers in the default mode, as we support running a blocking
+        // modal inside a Winit event handler (see [#1779]) which outrules the modal panel mode, and
+        // resizing such panel window enters the event tracking run loop mode, so we can't directly
+        // trigger events inside that mode either.
+        //
+        // Any events that are queued while running a modal or when live-resizing will instead wait,
+        // and be delivered to the application afterwards.
+        //
+        // [#1779]: https://github.com/rust-windowing/winit/issues/1779
+        let mode = unsafe { kCFRunLoopDefaultMode as CFTypeRef };
+
+        // SAFETY: The runloop is valid, the mode is a `CFStringRef`, and the block is `'static`.
+        unsafe { CFRunLoopPerformBlock(self.0, mode, &block) }
+    }
 }
 
-pub fn setup_control_flow_observers(panic_info: Weak<PanicInfo>) {
+pub fn setup_control_flow_observers(mtm: MainThreadMarker, panic_info: Weak<PanicInfo>) {
+    let run_loop = RunLoop::main(mtm);
     unsafe {
         let mut context = CFRunLoopObserverContext {
             info: Weak::into_raw(panic_info) as *mut _,
@@ -125,16 +212,15 @@ pub fn setup_control_flow_observers(panic_info: Weak<PanicInfo>) {
             release: None,
             copyDescription: None,
         };
-        let run_loop = RunLoop::get();
         run_loop.add_observer(
             kCFRunLoopAfterWaiting,
-            CFIndex::min_value(),
+            CFIndex::MIN,
             control_flow_begin_handler,
             &mut context as *mut _,
         );
         run_loop.add_observer(
             kCFRunLoopExit | kCFRunLoopBeforeWaiting,
-            CFIndex::max_value(),
+            CFIndex::MAX,
             control_flow_end_handler,
             &mut context as *mut _,
         );
@@ -165,8 +251,8 @@ impl Drop for EventLoopWaker {
     }
 }
 
-impl Default for EventLoopWaker {
-    fn default() -> EventLoopWaker {
+impl EventLoopWaker {
+    pub(crate) fn new() -> Self {
         extern "C" fn wakeup_main_loop(_timer: CFRunLoopTimerRef, _info: *mut c_void) {}
         unsafe {
             // Create a timer with a 0.1µs interval (1ns does not work) to mimic polling.
@@ -174,7 +260,7 @@ impl Default for EventLoopWaker {
             // future, but that gets changed to fire immediately in did_finish_launching
             let timer = CFRunLoopTimerCreate(
                 ptr::null_mut(),
-                std::f64::MAX,
+                f64::MAX,
                 0.000_000_1,
                 0,
                 0,
@@ -182,23 +268,21 @@ impl Default for EventLoopWaker {
                 ptr::null_mut(),
             );
             CFRunLoopAddTimer(CFRunLoopGetMain(), timer, kCFRunLoopCommonModes);
-            EventLoopWaker { timer, start_instant: Instant::now(), next_fire_date: None }
+            Self { timer, start_instant: Instant::now(), next_fire_date: None }
         }
     }
-}
 
-impl EventLoopWaker {
     pub fn stop(&mut self) {
         if self.next_fire_date.is_some() {
             self.next_fire_date = None;
-            unsafe { CFRunLoopTimerSetNextFireDate(self.timer, std::f64::MAX) }
+            unsafe { CFRunLoopTimerSetNextFireDate(self.timer, f64::MAX) }
         }
     }
 
     pub fn start(&mut self) {
         if self.next_fire_date != Some(self.start_instant) {
             self.next_fire_date = Some(self.start_instant);
-            unsafe { CFRunLoopTimerSetNextFireDate(self.timer, std::f64::MIN) }
+            unsafe { CFRunLoopTimerSetNextFireDate(self.timer, f64::MIN) }
         }
     }
 

src/platform_impl/apple/appkit/util.rs

@@ -1,11 +1,9 @@
-use objc2_foundation::{NSNotFound, NSRange, NSUInteger};
 use tracing::trace;
 
-pub static EMPTY_RANGE: NSRange = NSRange { location: NSNotFound as NSUInteger, length: 0 };
-
 macro_rules! trace_scope {
     ($s:literal) => {
-        let _crate = $crate::platform_impl::platform::util::TraceGuard::new(module_path!(), $s);
+        let _crate =
+            $crate::platform_impl::platform::appkit::util::TraceGuard::new(module_path!(), $s);
     };
 }
 

src/platform_impl/apple/appkit/view.rs

@@ -3,29 +3,27 @@ use std::cell::{Cell, RefCell};
 use std::collections::{HashMap, VecDeque};
 use std::ptr;
 
-use objc2::rc::{Id, WeakId};
+use objc2::rc::{Retained, WeakId};
 use objc2::runtime::{AnyObject, Sel};
-use objc2::{
-    class, declare_class, msg_send, msg_send_id, mutability, sel, ClassType, DeclaredClass,
-};
+use objc2::{declare_class, msg_send_id, mutability, sel, ClassType, DeclaredClass};
 use objc2_app_kit::{
     NSApplication, NSCursor, NSEvent, NSEventPhase, NSResponder, NSTextInputClient,
-    NSTrackingRectTag, NSView,
+    NSTrackingRectTag, NSView, NSViewFrameDidChangeNotification,
 };
 use objc2_foundation::{
     MainThreadMarker, NSArray, NSAttributedString, NSAttributedStringKey, NSCopying,
-    NSMutableAttributedString, NSObject, NSObjectProtocol, NSPoint, NSRange, NSRect, NSSize,
-    NSString, NSUInteger,
+    NSMutableAttributedString, NSNotFound, NSNotificationCenter, NSObject, NSObjectProtocol,
+    NSPoint, NSRange, NSRect, NSSize, NSString, NSUInteger,
 };
 
-use super::app_delegate::ApplicationDelegate;
+use super::app_state::ApplicationDelegate;
 use super::cursor::{default_cursor, invisible_cursor};
 use super::event::{
     code_to_key, code_to_location, create_key_event, event_mods, lalt_pressed, ralt_pressed,
     scancode_to_physicalkey,
 };
 use super::window::WinitWindow;
-use super::{util, DEVICE_ID};
+use super::DEVICE_ID;
 use crate::dpi::{LogicalPosition, LogicalSize};
 use crate::event::{
     DeviceEvent, ElementState, Ime, Modifiers, MouseButton, MouseScrollDelta, TouchPhase,
@@ -33,11 +31,12 @@ use crate::event::{
 };
 use crate::keyboard::{Key, KeyCode, KeyLocation, ModifiersState, NamedKey};
 use crate::platform::macos::OptionAsAlt;
+use crate::window::WindowId as RootWindowId;
 
 #[derive(Debug)]
 struct CursorState {
     visible: bool,
-    cursor: Id<NSCursor>,
+    cursor: Retained<NSCursor>,
 }
 
 impl Default for CursorState {
@@ -110,8 +109,11 @@ fn get_left_modifier_code(key: &Key) -> KeyCode {
     }
 }
 
-#[derive(Debug, Default)]
+#[derive(Debug)]
 pub struct ViewState {
+    /// Strong reference to the global application state.
+    app_delegate: Retained<ApplicationDelegate>,
+
     cursor_state: RefCell<CursorState>,
     ime_position: Cell<NSPoint>,
     ime_size: Cell<NSSize>,
@@ -130,7 +132,7 @@ pub struct ViewState {
     /// to the application, even during IME
     forward_key_to_app: Cell<bool>,
 
-    marked_text: RefCell<Id<NSMutableAttributedString>>,
+    marked_text: RefCell<Retained<NSMutableAttributedString>>,
     accepts_first_mouse: bool,
 
     // Weak reference because the window keeps a strong reference to the view
@@ -199,19 +201,15 @@ declare_class!(
         }
 
         #[method(drawRect:)]
-        fn draw_rect(&self, rect: NSRect) {
+        fn draw_rect(&self, _rect: NSRect) {
             trace_scope!("drawRect:");
 
             // It's a workaround for https://github.com/rust-windowing/winit/issues/2640, don't replace with `self.window_id()`.
             if let Some(window) = self.ivars()._ns_window.load() {
-                let app_delegate = ApplicationDelegate::get(MainThreadMarker::from(self));
-                app_delegate.handle_redraw(window.id());
+                self.ivars().app_delegate.handle_redraw(window.id());
             }
 
-            #[allow(clippy::let_unit_value)]
-            unsafe {
-                let _: () = msg_send![super(self), drawRect: rect];
-            }
+            // This is a direct subclass of NSView, no need to call superclass' drawRect:
         }
 
         #[method(acceptsFirstResponder)]
@@ -224,7 +222,7 @@ declare_class!(
         // IMKInputSession [0x7fc573576ff0 presentFunctionRowItemTextInputViewWithEndpoint:completionHandler:] : [self textInputContext]=0x7fc573558e10 *NO* NSRemoteViewController to client, NSError=Error Domain=NSCocoaErrorDomain Code=4099 "The connection from pid 0 was invalidated from this process." UserInfo={NSDebugDescription=The connection from pid 0 was invalidated from this process.}, com.apple.inputmethod.EmojiFunctionRowItem
         // TODO: Add an API extension for using `NSTouchBar`
         #[method_id(touchBar)]
-        fn touch_bar(&self) -> Option<Id<NSObject>> {
+        fn touch_bar(&self) -> Option<Retained<NSObject>> {
             trace_scope!("touchBar");
             None
         }
@@ -257,33 +255,36 @@ declare_class!(
             if length > 0 {
                 NSRange::new(0, length)
             } else {
-                util::EMPTY_RANGE
+                // Documented to return `{NSNotFound, 0}` if there is no marked range.
+                NSRange::new(NSNotFound as NSUInteger, 0)
             }
         }
 
         #[method(selectedRange)]
         fn selected_range(&self) -> NSRange {
             trace_scope!("selectedRange");
-            util::EMPTY_RANGE
+            // Documented to return `{NSNotFound, 0}` if there is no selection.
+            NSRange::new(NSNotFound as NSUInteger, 0)
         }
 
         #[method(setMarkedText:selectedRange:replacementRange:)]
         fn set_marked_text(
             &self,
             string: &NSObject,
-            _selected_range: NSRange,
+            selected_range: NSRange,
             _replacement_range: NSRange,
         ) {
+            // TODO: Use _replacement_range, requires changing the event to report surrounding text.
             trace_scope!("setMarkedText:selectedRange:replacementRange:");
 
             // SAFETY: This method is guaranteed to get either a `NSString` or a `NSAttributedString`.
-            let (marked_text, preedit_string) = if string.is_kind_of::<NSAttributedString>() {
+            let (marked_text, string) = if string.is_kind_of::<NSAttributedString>() {
                 let string: *const NSObject = string;
                 let string: *const NSAttributedString = string.cast();
                 let string = unsafe { &*string };
                 (
                     NSMutableAttributedString::from_attributed_nsstring(string),
-                    string.string().to_string(),
+                    string.string(),
                 )
             } else {
                 let string: *const NSObject = string;
@@ -291,7 +292,7 @@ declare_class!(
                 let string = unsafe { &*string };
                 (
                     NSMutableAttributedString::from_nsstring(string),
-                    string.to_string(),
+                    string.copy(),
                 )
             };
 
@@ -311,16 +312,21 @@ declare_class!(
                 self.ivars().ime_state.set(ImeState::Ground);
             }
 
-            // Empty string basically means that there's no preedit, so indicate that by sending
-            // `None` cursor range.
-            let cursor_range = if preedit_string.is_empty() {
+            let cursor_range = if string.is_empty() {
+                // An empty string basically means that there's no preedit, so indicate that by
+                // sending a `None` cursor range.
                 None
             } else {
-                Some((preedit_string.len(), preedit_string.len()))
+                // Convert the selected range from UTF-16 indices to UTF-8 indices.
+                let sub_string_a = unsafe { string.substringToIndex(selected_range.location) };
+                let sub_string_b = unsafe { string.substringToIndex(selected_range.end()) };
+                let lowerbound_utf8 = sub_string_a.len();
+                let upperbound_utf8 = sub_string_b.len();
+                Some((lowerbound_utf8, upperbound_utf8))
             };
 
             // Send WindowEvent for updating marked text
-            self.queue_event(WindowEvent::Ime(Ime::Preedit(preedit_string, cursor_range)));
+            self.queue_event(WindowEvent::Ime(Ime::Preedit(string.to_string(), cursor_range)));
         }
 
         #[method(unmarkText)]
@@ -341,7 +347,7 @@ declare_class!(
         }
 
         #[method_id(validAttributesForMarkedText)]
-        fn valid_attributes_for_marked_text(&self) -> Id<NSArray<NSAttributedStringKey>> {
+        fn valid_attributes_for_marked_text(&self) -> Retained<NSArray<NSAttributedStringKey>> {
             trace_scope!("validAttributesForMarkedText");
             NSArray::new()
         }
@@ -351,7 +357,7 @@ declare_class!(
             &self,
             _range: NSRange,
             _actual_range: *mut NSRange,
-        ) -> Option<Id<NSAttributedString>> {
+        ) -> Option<Retained<NSAttributedString>> {
             trace_scope!("attributedSubstringForProposedRange:actualRange:");
             None
         }
@@ -380,6 +386,7 @@ declare_class!(
 
         #[method(insertText:replacementRange:)]
         fn insert_text(&self, string: &NSObject, _replacement_range: NSRange) {
+            // TODO: Use _replacement_range, requires changing the event to report surrounding text.
             trace_scope!("insertText:replacementRange:");
 
             // SAFETY: This method is guaranteed to get either a `NSString` or a `NSAttributedString`.
@@ -680,7 +687,9 @@ declare_class!(
 
             self.update_modifiers(event, false);
 
-            self.queue_device_event(DeviceEvent::MouseWheel { delta });
+            self.ivars().app_delegate.maybe_queue_with_handler(move |app, event_loop|
+                app.device_event(event_loop, DEVICE_ID, DeviceEvent::MouseWheel { delta })
+            );
             self.queue_event(WindowEvent::MouseWheel {
                 device_id: DEVICE_ID,
                 delta,
@@ -773,34 +782,40 @@ declare_class!(
 
 impl WinitView {
     pub(super) fn new(
+        app_delegate: &ApplicationDelegate,
         window: &WinitWindow,
         accepts_first_mouse: bool,
         option_as_alt: OptionAsAlt,
-    ) -> Id<Self> {
+    ) -> Retained<Self> {
         let mtm = MainThreadMarker::from(window);
         let this = mtm.alloc().set_ivars(ViewState {
+            app_delegate: app_delegate.retain(),
+            cursor_state: Default::default(),
+            ime_position: Default::default(),
+            ime_size: Default::default(),
+            modifiers: Default::default(),
+            phys_modifiers: Default::default(),
+            tracking_rect: Default::default(),
+            ime_state: Default::default(),
+            input_source: Default::default(),
+            ime_allowed: Default::default(),
+            forward_key_to_app: Default::default(),
+            marked_text: Default::default(),
             accepts_first_mouse,
             _ns_window: WeakId::new(&window.retain()),
             option_as_alt: Cell::new(option_as_alt),
-            ..Default::default()
         });
-        let this: Id<Self> = unsafe { msg_send_id![super(this), init] };
+        let this: Retained<Self> = unsafe { msg_send_id![super(this), init] };
 
         this.setPostsFrameChangedNotifications(true);
-        let notification_center: &AnyObject =
-            unsafe { msg_send![class!(NSNotificationCenter), defaultCenter] };
-        // About frame change
-        let frame_did_change_notification_name =
-            NSString::from_str("NSViewFrameDidChangeNotification");
-        #[allow(clippy::let_unit_value)]
+        let notification_center = unsafe { NSNotificationCenter::defaultCenter() };
         unsafe {
-            let _: () = msg_send![
-                notification_center,
-                addObserver: &*this,
-                selector: sel!(frameDidChange:),
-                name: &*frame_did_change_notification_name,
-                object: &*this,
-            ];
+            notification_center.addObserver_selector_name_object(
+                &this,
+                sel!(frameDidChange:),
+                Some(NSViewFrameDidChangeNotification),
+                Some(&this),
+            )
         }
 
         *this.ivars().input_source.borrow_mut() = this.current_input_source();
@@ -808,7 +823,7 @@ impl WinitView {
         this
     }
 
-    fn window(&self) -> Id<WinitWindow> {
+    fn window(&self) -> Retained<WinitWindow> {
         // TODO: Simply use `window` property on `NSView`.
         // That only returns a window _after_ the view has been attached though!
         // (which is incompatible with `frameDidChange:`)
@@ -818,13 +833,10 @@ impl WinitView {
     }
 
     fn queue_event(&self, event: WindowEvent) {
-        let app_delegate = ApplicationDelegate::get(MainThreadMarker::from(self));
-        app_delegate.queue_window_event(self.window().id(), event);
-    }
-
-    fn queue_device_event(&self, event: DeviceEvent) {
-        let app_delegate = ApplicationDelegate::get(MainThreadMarker::from(self));
-        app_delegate.queue_device_event(event);
+        let window_id = RootWindowId(self.window().id());
+        self.ivars().app_delegate.maybe_queue_with_handler(move |app, event_loop| {
+            app.window_event(event_loop, window_id, event);
+        });
     }
 
     fn scale_factor(&self) -> f64 {
@@ -843,11 +855,11 @@ impl WinitView {
             .unwrap_or_default()
     }
 
-    pub(super) fn cursor_icon(&self) -> Id<NSCursor> {
+    pub(super) fn cursor_icon(&self) -> Retained<NSCursor> {
         self.ivars().cursor_state.borrow().cursor.clone()
     }
 
-    pub(super) fn set_cursor_icon(&self, icon: Id<NSCursor>) {
+    pub(super) fn set_cursor_icon(&self, icon: Retained<NSCursor>) {
         let mut cursor_state = self.ivars().cursor_state.borrow_mut();
         cursor_state.cursor = icon;
     }
@@ -1080,7 +1092,7 @@ fn mouse_button(event: &NSEvent) -> MouseButton {
 // NOTE: to get option as alt working we need to rewrite events
 // we're getting from the operating system, which makes it
 // impossible to provide such events as extra in `KeyEvent`.
-fn replace_event(event: &NSEvent, option_as_alt: OptionAsAlt) -> Id<NSEvent> {
+fn replace_event(event: &NSEvent, option_as_alt: OptionAsAlt) -> Retained<NSEvent> {
     let ev_mods = event_mods(event).state;
     let ignore_alt_characters = match option_as_alt {
         OptionAsAlt::OnlyLeft if lalt_pressed(event) => true,

src/platform_impl/apple/appkit/window.rs

@@ -1,6 +1,6 @@
 #![allow(clippy::unnecessary_cast)]
 
-use objc2::rc::{autoreleasepool, Id};
+use objc2::rc::{autoreleasepool, Retained};
 use objc2::{declare_class, mutability, ClassType, DeclaredClass};
 use objc2_app_kit::{NSResponder, NSWindow};
 use objc2_foundation::{MainThreadBound, MainThreadMarker, NSObject};
@@ -11,9 +11,9 @@ use crate::error::OsError as RootOsError;
 use crate::window::WindowAttributes;
 
 pub(crate) struct Window {
-    window: MainThreadBound<Id<WinitWindow>>,
+    window: MainThreadBound<Retained<WinitWindow>>,
     /// The window only keeps a weak reference to this, so we must keep it around here.
-    delegate: MainThreadBound<Id<WindowDelegate>>,
+    delegate: MainThreadBound<Retained<WindowDelegate>>,
 }
 
 impl Drop for Window {
@@ -28,7 +28,9 @@ impl Window {
         attributes: WindowAttributes,
     ) -> Result<Self, RootOsError> {
         let mtm = window_target.mtm;
-        let delegate = autoreleasepool(|_| WindowDelegate::new(attributes, mtm))?;
+        let delegate = autoreleasepool(|_| {
+            WindowDelegate::new(window_target.app_delegate(), attributes, mtm)
+        })?;
         Ok(Window {
             window: MainThreadBound::new(delegate.window().retain(), mtm),
             delegate: MainThreadBound::new(delegate, mtm),
@@ -72,7 +74,7 @@ impl Window {
 pub struct WindowId(pub usize);
 
 impl WindowId {
-    pub const unsafe fn dummy() -> Self {
+    pub const fn dummy() -> Self {
         Self(0)
     }
 }

src/platform_impl/apple/appkit/window_delegate.rs

@@ -1,44 +1,48 @@
 #![allow(clippy::unnecessary_cast)]
 use std::cell::{Cell, RefCell};
 use std::collections::VecDeque;
+use std::ffi::c_void;
 use std::ptr;
+use std::sync::{Arc, Mutex};
 
 use core_graphics::display::{CGDisplay, CGPoint};
 use monitor::VideoModeHandle;
-use objc2::rc::{autoreleasepool, Id};
+use objc2::rc::{autoreleasepool, Retained};
 use objc2::runtime::{AnyObject, ProtocolObject};
-use objc2::{
-    class, declare_class, msg_send, msg_send_id, mutability, sel, ClassType, DeclaredClass,
-};
+use objc2::{declare_class, msg_send_id, mutability, sel, ClassType, DeclaredClass};
 use objc2_app_kit::{
-    NSAppKitVersionNumber, NSAppKitVersionNumber10_12, NSAppearance, NSApplication,
-    NSApplicationPresentationOptions, NSBackingStoreType, NSDraggingDestination,
-    NSFilenamesPboardType, NSPasteboard, NSRequestUserAttentionType, NSScreen, NSView,
-    NSWindowButton, NSWindowDelegate, NSWindowFullScreenButton, NSWindowLevel,
-    NSWindowOcclusionState, NSWindowOrderingMode, NSWindowSharingType, NSWindowStyleMask,
-    NSWindowTabbingMode, NSWindowTitleVisibility,
+    NSAppKitVersionNumber, NSAppKitVersionNumber10_12, NSAppearance, NSAppearanceCustomization,
+    NSAppearanceNameAqua, NSApplication, NSApplicationPresentationOptions, NSBackingStoreType,
+    NSColor, NSDraggingDestination, NSFilenamesPboardType, NSPasteboard,
+    NSRequestUserAttentionType, NSScreen, NSView, NSWindowButton, NSWindowDelegate,
+    NSWindowFullScreenButton, NSWindowLevel, NSWindowOcclusionState, NSWindowOrderingMode,
+    NSWindowSharingType, NSWindowStyleMask, NSWindowTabbingMode, NSWindowTitleVisibility,
 };
 use objc2_foundation::{
-    CGFloat, MainThreadMarker, NSArray, NSCopying, NSObject, NSObjectProtocol, NSPoint, NSRect,
-    NSSize, NSString,
+    ns_string, CGFloat, MainThreadMarker, NSArray, NSCopying, NSDictionary, NSKeyValueChangeKey,
+    NSKeyValueChangeNewKey, NSKeyValueChangeOldKey, NSKeyValueObservingOptions, NSObject,
+    NSObjectNSDelayedPerforming, NSObjectNSKeyValueObserverRegistration, NSObjectProtocol, NSPoint,
+    NSRect, NSSize, NSString,
 };
+use tracing::{trace, warn};
 
-use super::app_delegate::ApplicationDelegate;
+use super::app_state::ApplicationDelegate;
 use super::cursor::cursor_from_icon;
 use super::monitor::{self, flip_window_screen_coordinates, get_display_id};
+use super::observer::RunLoop;
 use super::view::WinitView;
 use super::window::WinitWindow;
 use super::{ffi, Fullscreen, MonitorHandle, OsError, WindowId};
 use crate::dpi::{LogicalPosition, LogicalSize, PhysicalPosition, PhysicalSize, Position, Size};
 use crate::error::{ExternalError, NotSupportedError, OsError as RootOsError};
-use crate::event::WindowEvent;
+use crate::event::{InnerSizeWriter, WindowEvent};
 use crate::platform::macos::{OptionAsAlt, WindowExtMacOS};
 use crate::window::{
     Cursor, CursorGrabMode, Icon, ImePurpose, ResizeDirection, Theme, UserAttentionType,
-    WindowAttributes, WindowButtons, WindowLevel,
+    WindowAttributes, WindowButtons, WindowId as RootWindowId, WindowLevel,
 };
 
-#[derive(Clone, Debug)]
+#[derive(Clone, Debug, PartialEq)]
 pub struct PlatformSpecificWindowAttributes {
     pub movable_by_window_background: bool,
     pub titlebar_transparent: bool,
@@ -74,9 +78,10 @@ impl Default for PlatformSpecificWindowAttributes {
 
 #[derive(Debug)]
 pub(crate) struct State {
-    window: Id<WinitWindow>,
+    /// Strong reference to the global application state.
+    app_delegate: Retained<ApplicationDelegate>,
 
-    current_theme: Cell<Option<Theme>>,
+    window: Retained<WinitWindow>,
 
     // During `windowDidResize`, we use this to only send Moved if the position changed.
     //
@@ -183,7 +188,17 @@ declare_class!(
         #[method(windowDidChangeBackingProperties:)]
         fn window_did_change_backing_properties(&self, _: Option<&AnyObject>) {
             trace_scope!("windowDidChangeBackingProperties:");
-            self.queue_static_scale_factor_changed_event();
+            let scale_factor = self.scale_factor();
+            if scale_factor == self.ivars().previous_scale_factor.get() {
+                return;
+            };
+            self.ivars().previous_scale_factor.set(scale_factor);
+
+            let mtm = MainThreadMarker::from(self);
+            let this = self.retain();
+            RunLoop::main(mtm).queue_closure(move || {
+                this.handle_scale_factor_changed(scale_factor);
+            });
         }
 
         #[method(windowDidBecomeKey:)]
@@ -230,7 +245,7 @@ declare_class!(
                 None => {
                     let current_monitor = self.current_monitor_inner();
                     *fullscreen = Some(Fullscreen::Borderless(current_monitor));
-                }
+                },
             }
             self.ivars().in_fullscreen_transition.set(true);
         }
@@ -261,11 +276,9 @@ declare_class!(
             let mut options = proposed_options;
             let fullscreen = self.ivars().fullscreen.borrow();
             if let Some(Fullscreen::Exclusive(_)) = &*fullscreen {
-                options = NSApplicationPresentationOptions(
-                    NSApplicationPresentationOptions::NSApplicationPresentationFullScreen.0
-                        | NSApplicationPresentationOptions::NSApplicationPresentationHideDock.0
-                        | NSApplicationPresentationOptions::NSApplicationPresentationHideMenuBar.0,
-                );
+                options = NSApplicationPresentationOptions::NSApplicationPresentationFullScreen
+                    | NSApplicationPresentationOptions::NSApplicationPresentationHideDock
+                    | NSApplicationPresentationOptions::NSApplicationPresentationHideMenuBar;
             }
 
             options
@@ -316,14 +329,12 @@ declare_class!(
             self.ivars().in_fullscreen_transition.set(false);
             self.ivars().target_fullscreen.replace(None);
             if self.ivars().initial_fullscreen.get() {
-                #[allow(clippy::let_unit_value)]
                 unsafe {
-                    let _: () = msg_send![
-                        self.window(),
-                        performSelector: sel!(toggleFullScreen:),
-                        withObject: ptr::null::<AnyObject>(),
-                        afterDelay: 0.5,
-                    ];
+                    self.window().performSelector_withObject_afterDelay(
+                        sel!(toggleFullScreen:),
+                        None,
+                        0.5,
+                    )
                 };
             } else {
                 self.restore_state_from_fullscreen();
@@ -334,8 +345,7 @@ declare_class!(
         #[method(windowDidChangeOcclusionState:)]
         fn window_did_change_occlusion_state(&self, _: Option<&AnyObject>) {
             trace_scope!("windowDidChangeOcclusionState:");
-            let visible = self.window().occlusionState().0 & NSWindowOcclusionState::Visible.0
-                == NSWindowOcclusionState::Visible.0;
+            let visible = self.window().occlusionState().contains(NSWindowOcclusionState::Visible);
             self.queue_event(WindowEvent::Occluded(!visible));
         }
 
@@ -359,11 +369,9 @@ declare_class!(
 
             use std::path::PathBuf;
 
-            let pb: Id<NSPasteboard> = unsafe { msg_send_id![sender, draggingPasteboard] };
-            let filenames = pb
-                .propertyListForType(unsafe { NSFilenamesPboardType })
-                .unwrap();
-            let filenames: Id<NSArray<NSString>> = unsafe { Id::cast(filenames) };
+            let pb: Retained<NSPasteboard> = unsafe { msg_send_id![sender, draggingPasteboard] };
+            let filenames = pb.propertyListForType(unsafe { NSFilenamesPboardType }).unwrap();
+            let filenames: Retained<NSArray<NSString>> = unsafe { Retained::cast(filenames) };
 
             filenames.into_iter().for_each(|file| {
                 let path = PathBuf::from(file.to_string());
@@ -387,11 +395,9 @@ declare_class!(
 
             use std::path::PathBuf;
 
-            let pb: Id<NSPasteboard> = unsafe { msg_send_id![sender, draggingPasteboard] };
-            let filenames = pb
-                .propertyListForType(unsafe { NSFilenamesPboardType })
-                .unwrap();
-            let filenames: Id<NSArray<NSString>> = unsafe { Id::cast(filenames) };
+            let pb: Retained<NSPasteboard> = unsafe { msg_send_id![sender, draggingPasteboard] };
+            let filenames = pb.propertyListForType(unsafe { NSFilenamesPboardType }).unwrap();
+            let filenames: Retained<NSArray<NSString>> = unsafe { Retained::cast(filenames) };
 
             filenames.into_iter().for_each(|file| {
                 let path = PathBuf::from(file.to_string());
@@ -415,34 +421,71 @@ declare_class!(
         }
     }
 
+    // Key-Value Observing
     unsafe impl WindowDelegate {
-        // Observe theme change
-        #[method(effectiveAppearanceDidChange:)]
-        fn effective_appearance_did_change(this: *mut Self, sender: Option<&AnyObject>) {
-            trace_scope!("effectiveAppearanceDidChange:");
-            unsafe {
-                msg_send![
-                    this,
-                    performSelectorOnMainThread: sel!(effectiveAppearanceDidChangedOnMainThread:),
-                    withObject: sender,
-                    waitUntilDone: false,
-                ]
-            }
-        }
+        #[method(observeValueForKeyPath:ofObject:change:context:)]
+        fn observe_value(
+            &self,
+            key_path: Option<&NSString>,
+            _object: Option<&AnyObject>,
+            change: Option<&NSDictionary<NSKeyValueChangeKey, AnyObject>>,
+            _context: *mut c_void,
+        ) {
+            trace_scope!("observeValueForKeyPath:ofObject:change:context:");
+            // NOTE: We don't _really_ need to check the key path, as there should only be one, but
+            // in the future we might want to observe other key paths.
+            if key_path == Some(ns_string!("effectiveAppearance")) {
+                let change = change.expect("requested a change dictionary in `addObserver`, but none was provided");
+                let old = change.get(unsafe { NSKeyValueChangeOldKey }).expect("requested change dictionary did not contain `NSKeyValueChangeOldKey`");
+                let new = change.get(unsafe { NSKeyValueChangeNewKey }).expect("requested change dictionary did not contain `NSKeyValueChangeNewKey`");
 
-        #[method(effectiveAppearanceDidChangedOnMainThread:)]
-        fn effective_appearance_did_changed_on_main_thread(&self, _: Option<&AnyObject>) {
-            let mtm = MainThreadMarker::from(self);
-            let theme = get_ns_theme(mtm);
-            let old_theme = self.ivars().current_theme.replace(Some(theme));
-            if old_theme != Some(theme) {
-                self.queue_event(WindowEvent::ThemeChanged(theme));
+                // SAFETY: The value of `effectiveAppearance` is `NSAppearance`
+                let old: *const AnyObject = old;
+                let old: *const NSAppearance = old.cast();
+                let old: &NSAppearance = unsafe { &*old };
+                let new: *const AnyObject = new;
+                let new: *const NSAppearance = new.cast();
+                let new: &NSAppearance = unsafe { &*new };
+
+                trace!(old = %unsafe { old.name() }, new = %unsafe { new.name() }, "effectiveAppearance changed");
+
+                // Ignore the change if the window's theme is customized by the user (since in that
+                // case the `effectiveAppearance` is only emitted upon said customization, and then
+                // it's triggered directly by a user action, and we don't want to emit the event).
+                if unsafe { self.window().appearance() }.is_some() {
+                    return;
+                }
+
+                let old = appearance_to_theme(old);
+                let new = appearance_to_theme(new);
+                // Check that the theme changed in Winit's terms (the theme might have changed on
+                // other parameters, such as level of contrast, but the event should not be emitted
+                // in those cases).
+                if old == new {
+                    return;
+                }
+
+                self.queue_event(WindowEvent::ThemeChanged(new));
+            } else {
+                panic!("unknown observed keypath {key_path:?}");
             }
         }
     }
 );
 
-fn new_window(attrs: &WindowAttributes, mtm: MainThreadMarker) -> Option<Id<WinitWindow>> {
+impl Drop for WindowDelegate {
+    fn drop(&mut self) {
+        unsafe {
+            self.window().removeObserver_forKeyPath(self, ns_string!("effectiveAppearance"));
+        }
+    }
+}
+
+fn new_window(
+    app_delegate: &ApplicationDelegate,
+    attrs: &WindowAttributes,
+    mtm: MainThreadMarker,
+) -> Option<Retained<WinitWindow>> {
     autoreleasepool(|_| {
         let screen = match attrs.fullscreen.clone().map(Into::into) {
             Some(Fullscreen::Borderless(Some(monitor)))
@@ -487,38 +530,38 @@ fn new_window(attrs: &WindowAttributes, mtm: MainThreadMarker) -> Option<Id<Wini
             // if decorations is set to false, ignore pl_attrs
             //
             // if the titlebar is hidden, ignore other pl_attrs
-            NSWindowStyleMask::Borderless.0
-                | NSWindowStyleMask::Resizable.0
-                | NSWindowStyleMask::Miniaturizable.0
+            NSWindowStyleMask::Borderless
+                | NSWindowStyleMask::Resizable
+                | NSWindowStyleMask::Miniaturizable
         } else {
             // default case, resizable window with titlebar and titlebar buttons
-            NSWindowStyleMask::Closable.0
-                | NSWindowStyleMask::Miniaturizable.0
-                | NSWindowStyleMask::Resizable.0
-                | NSWindowStyleMask::Titled.0
+            NSWindowStyleMask::Closable
+                | NSWindowStyleMask::Miniaturizable
+                | NSWindowStyleMask::Resizable
+                | NSWindowStyleMask::Titled
         };
 
         if !attrs.resizable {
-            masks &= !NSWindowStyleMask::Resizable.0;
+            masks &= !NSWindowStyleMask::Resizable;
         }
 
         if !attrs.enabled_buttons.contains(WindowButtons::MINIMIZE) {
-            masks &= !NSWindowStyleMask::Miniaturizable.0;
+            masks &= !NSWindowStyleMask::Miniaturizable;
         }
 
         if !attrs.enabled_buttons.contains(WindowButtons::CLOSE) {
-            masks &= !NSWindowStyleMask::Closable.0;
+            masks &= !NSWindowStyleMask::Closable;
         }
 
         if attrs.platform_specific.fullsize_content_view {
-            masks |= NSWindowStyleMask::FullSizeContentView.0;
+            masks |= NSWindowStyleMask::FullSizeContentView;
         }
 
-        let window: Option<Id<WinitWindow>> = unsafe {
+        let window: Option<Retained<WinitWindow>> = unsafe {
             msg_send_id![
                 super(mtm.alloc().set_ivars(())),
                 initWithContentRect: frame,
-                styleMask: NSWindowStyleMask(masks),
+                styleMask: masks,
                 backing: NSBackingStoreType::NSBackingStoreBuffered,
                 defer: false,
             ]
@@ -579,6 +622,7 @@ fn new_window(attrs: &WindowAttributes, mtm: MainThreadMarker) -> Option<Id<Wini
         }
 
         let view = WinitView::new(
+            app_delegate,
             &window,
             attrs.platform_specific.accepts_first_mouse,
             attrs.platform_specific.option_as_alt,
@@ -605,6 +649,8 @@ fn new_window(attrs: &WindowAttributes, mtm: MainThreadMarker) -> Option<Id<Wini
 
         if attrs.transparent {
             window.setOpaque(false);
+            // See `set_transparent` for details on why we do this.
+            window.setBackgroundColor(unsafe { Some(&NSColor::clearColor()) });
         }
 
         // register for drag and drop operations.
@@ -618,8 +664,12 @@ fn new_window(attrs: &WindowAttributes, mtm: MainThreadMarker) -> Option<Id<Wini
 }
 
 impl WindowDelegate {
-    pub fn new(attrs: WindowAttributes, mtm: MainThreadMarker) -> Result<Id<Self>, RootOsError> {
-        let window = new_window(&attrs, mtm)
+    pub(super) fn new(
+        app_delegate: &ApplicationDelegate,
+        attrs: WindowAttributes,
+        mtm: MainThreadMarker,
+    ) -> Result<Retained<Self>, RootOsError> {
+        let window = new_window(app_delegate, &attrs, mtm)
             .ok_or_else(|| os_error!(OsError::CreationError("couldn't create `NSWindow`")))?;
 
         #[cfg(feature = "rwh_06")]
@@ -627,8 +677,8 @@ impl WindowDelegate {
             Some(rwh_06::RawWindowHandle::AppKit(handle)) => {
                 // SAFETY: Caller ensures the pointer is valid or NULL
                 // Unwrap is fine, since the pointer comes from `NonNull`.
-                let parent_view: Id<NSView> =
-                    unsafe { Id::retain(handle.ns_view.as_ptr().cast()) }.unwrap();
+                let parent_view: Retained<NSView> =
+                    unsafe { Retained::retain(handle.ns_view.as_ptr().cast()) }.unwrap();
                 let parent = parent_view.window().ok_or_else(|| {
                     os_error!(OsError::CreationError("parent view should be installed in a window"))
                 })?;
@@ -654,14 +704,13 @@ impl WindowDelegate {
 
         let scale_factor = window.backingScaleFactor() as _;
 
-        let current_theme = match attrs.preferred_theme {
-            Some(theme) => Some(theme),
-            None => Some(get_ns_theme(mtm)),
-        };
+        if let Some(appearance) = theme_to_appearance(attrs.preferred_theme) {
+            unsafe { window.setAppearance(Some(&appearance)) };
+        }
 
         let delegate = mtm.alloc().set_ivars(State {
+            app_delegate: app_delegate.retain(),
             window: window.retain(),
-            current_theme: Cell::new(current_theme),
             previous_position: Cell::new(None),
             previous_scale_factor: Cell::new(scale_factor),
             resize_increments: Cell::new(resize_increments),
@@ -677,25 +726,27 @@ impl WindowDelegate {
             is_simple_fullscreen: Cell::new(false),
             saved_style: Cell::new(None),
         });
-        let delegate: Id<WindowDelegate> = unsafe { msg_send_id![super(delegate), init] };
+        let delegate: Retained<WindowDelegate> = unsafe { msg_send_id![super(delegate), init] };
 
         if scale_factor != 1.0 {
-            delegate.queue_static_scale_factor_changed_event();
+            let delegate = delegate.clone();
+            RunLoop::main(mtm).queue_closure(move || {
+                delegate.handle_scale_factor_changed(scale_factor);
+            });
         }
         window.setDelegate(Some(ProtocolObject::from_ref(&*delegate)));
 
-        // Enable theme change event
-        let notification_center: Id<AnyObject> =
-            unsafe { msg_send_id![class!(NSDistributedNotificationCenter), defaultCenter] };
-        let notification_name = NSString::from_str("AppleInterfaceThemeChangedNotification");
-        let _: () = unsafe {
-            msg_send![
-                &notification_center,
-                addObserver: &*delegate,
-                selector: sel!(effectiveAppearanceDidChange:),
-                name: &*notification_name,
-                object: ptr::null::<AnyObject>(),
-            ]
+        // Listen for theme change event.
+        //
+        // SAFETY: The observer is un-registered in the `Drop` of the delegate.
+        unsafe {
+            window.addObserver_forKeyPath_options_context(
+                &delegate,
+                ns_string!("effectiveAppearance"),
+                NSKeyValueObservingOptions::NSKeyValueObservingOptionNew
+                    | NSKeyValueObservingOptions::NSKeyValueObservingOptionOld,
+                ptr::null_mut(),
+            )
         };
 
         if attrs.blur {
@@ -740,9 +791,9 @@ impl WindowDelegate {
     }
 
     #[track_caller]
-    pub(super) fn view(&self) -> Id<WinitView> {
+    pub(super) fn view(&self) -> Retained<WinitView> {
         // SAFETY: The view inside WinitWindow is always `WinitView`
-        unsafe { Id::cast(self.window().contentView().unwrap()) }
+        unsafe { Retained::cast(self.window().contentView().unwrap()) }
     }
 
     #[track_caller]
@@ -756,26 +807,33 @@ impl WindowDelegate {
     }
 
     pub(crate) fn queue_event(&self, event: WindowEvent) {
-        let app_delegate = ApplicationDelegate::get(MainThreadMarker::from(self));
-        app_delegate.queue_window_event(self.window().id(), event);
+        let window_id = RootWindowId(self.window().id());
+        self.ivars().app_delegate.maybe_queue_with_handler(move |app, event_loop| {
+            app.window_event(event_loop, window_id, event);
+        });
     }
 
-    fn queue_static_scale_factor_changed_event(&self) {
-        let scale_factor = self.scale_factor();
-        if scale_factor == self.ivars().previous_scale_factor.get() {
-            return;
-        };
+    fn handle_scale_factor_changed(&self, scale_factor: CGFloat) {
+        let window = self.window();
 
-        self.ivars().previous_scale_factor.set(scale_factor);
-        let content_size = self.window().contentRectForFrameRect(self.window().frame()).size;
+        let content_size = window.contentRectForFrameRect(window.frame()).size;
         let content_size = LogicalSize::new(content_size.width, content_size.height);
 
-        let app_delegate = ApplicationDelegate::get(MainThreadMarker::from(self));
-        app_delegate.queue_static_scale_factor_changed_event(
-            self.window().retain(),
-            content_size.to_physical(scale_factor),
+        let suggested_size = content_size.to_physical(scale_factor);
+        let new_inner_size = Arc::new(Mutex::new(suggested_size));
+        self.queue_event(WindowEvent::ScaleFactorChanged {
             scale_factor,
-        );
+            inner_size_writer: InnerSizeWriter::new(Arc::downgrade(&new_inner_size)),
+        });
+        let physical_size = *new_inner_size.lock().unwrap();
+        drop(new_inner_size);
+
+        if physical_size != suggested_size {
+            let logical_size = physical_size.to_logical(scale_factor);
+            let size = NSSize::new(logical_size.width, logical_size.height);
+            window.setContentSize(size);
+        }
+        self.queue_event(WindowEvent::Resized(physical_size));
     }
 
     fn emit_move_event(&self) {
@@ -803,7 +861,23 @@ impl WindowDelegate {
     }
 
     pub fn set_transparent(&self, transparent: bool) {
-        self.window().setOpaque(!transparent)
+        // This is just a hint for Quartz, it doesn't actually speculate with window alpha.
+        // Providing a wrong value here could result in visual artifacts, when the window is
+        // transparent.
+        self.window().setOpaque(!transparent);
+
+        // AppKit draws the window with a background color by default, which is usually really
+        // nice, but gets in the way when we want to allow the contents of the window to be
+        // transparent, as in that case, the transparent contents will just be drawn on top of
+        // the background color. As such, to allow the window to be transparent, we must also set
+        // the background color to one with an empty alpha channel.
+        let color = if transparent {
+            unsafe { NSColor::clearColor() }
+        } else {
+            unsafe { NSColor::windowBackgroundColor() }
+        };
+
+        self.window().setBackgroundColor(Some(&color));
     }
 
     pub fn set_blur(&self, blur: bool) {
@@ -833,8 +907,7 @@ impl WindowDelegate {
     }
 
     pub fn request_redraw(&self) {
-        let app_delegate = ApplicationDelegate::get(MainThreadMarker::from(self));
-        app_delegate.queue_redraw(self.window().id());
+        self.ivars().app_delegate.queue_redraw(self.window().id());
     }
 
     #[inline]
@@ -903,8 +976,8 @@ impl WindowDelegate {
 
     pub fn set_max_inner_size(&self, dimensions: Option<Size>) {
         let dimensions = dimensions.unwrap_or(Size::Logical(LogicalSize {
-            width: std::f32::MAX as f64,
-            height: std::f32::MAX as f64,
+            width: f32::MAX as f64,
+            height: f32::MAX as f64,
         }));
         let scale_factor = self.scale_factor();
         let max_size = dimensions.to_logical::<CGFloat>(scale_factor);
@@ -958,13 +1031,13 @@ impl WindowDelegate {
         self.ivars().resizable.set(resizable);
         let fullscreen = self.ivars().fullscreen.borrow().is_some();
         if !fullscreen {
-            let mut mask = self.window().styleMask().0;
+            let mut mask = self.window().styleMask();
             if resizable {
-                mask |= NSWindowStyleMask::Resizable.0;
+                mask |= NSWindowStyleMask::Resizable;
             } else {
-                mask &= !NSWindowStyleMask::Resizable.0;
+                mask &= !NSWindowStyleMask::Resizable;
             }
-            self.set_style_mask(NSWindowStyleMask(mask));
+            self.set_style_mask(mask);
         }
         // Otherwise, we don't change the mask until we exit fullscreen.
     }
@@ -976,23 +1049,23 @@ impl WindowDelegate {
 
     #[inline]
     pub fn set_enabled_buttons(&self, buttons: WindowButtons) {
-        let mut mask = self.window().styleMask().0;
+        let mut mask = self.window().styleMask();
 
         if buttons.contains(WindowButtons::CLOSE) {
-            mask |= NSWindowStyleMask::Closable.0;
+            mask |= NSWindowStyleMask::Closable;
         } else {
-            mask &= !NSWindowStyleMask::Closable.0;
+            mask &= !NSWindowStyleMask::Closable;
         }
 
         if buttons.contains(WindowButtons::MINIMIZE) {
-            mask |= NSWindowStyleMask::Miniaturizable.0;
+            mask |= NSWindowStyleMask::Miniaturizable;
         } else {
-            mask &= !NSWindowStyleMask::Miniaturizable.0;
+            mask &= !NSWindowStyleMask::Miniaturizable;
         }
 
         // This must happen before the button's "enabled" status has been set,
         // hence we do it synchronously.
-        self.set_style_mask(NSWindowStyleMask(mask));
+        self.set_style_mask(mask);
 
         // We edit the button directly instead of using `NSResizableWindowMask`,
         // since that mask also affect the resizability of the window (which is
@@ -1113,9 +1186,8 @@ impl WindowDelegate {
         // we make it resizable temporarily.
         let curr_mask = self.window().styleMask();
 
-        let required =
-            NSWindowStyleMask(NSWindowStyleMask::Titled.0 | NSWindowStyleMask::Resizable.0);
-        let needs_temp_mask = !mask_contains(curr_mask, required);
+        let required = NSWindowStyleMask::Titled | NSWindowStyleMask::Resizable;
+        let needs_temp_mask = !curr_mask.contains(required);
         if needs_temp_mask {
             self.set_style_mask(required);
         }
@@ -1132,12 +1204,12 @@ impl WindowDelegate {
 
     fn saved_style(&self) -> NSWindowStyleMask {
         let base_mask =
-            self.ivars().saved_style.take().unwrap_or_else(|| self.window().styleMask()).0;
-        NSWindowStyleMask(if self.ivars().resizable.get() {
-            base_mask | NSWindowStyleMask::Resizable.0
+            self.ivars().saved_style.take().unwrap_or_else(|| self.window().styleMask());
+        if self.ivars().resizable.get() {
+            base_mask | NSWindowStyleMask::Resizable
         } else {
-            base_mask & !NSWindowStyleMask::Resizable.0
-        })
+            base_mask & !NSWindowStyleMask::Resizable
+        }
     }
 
     /// This is called when the window is exiting fullscreen, whether by the
@@ -1192,7 +1264,7 @@ impl WindowDelegate {
             return;
         }
 
-        if mask_contains(self.window().styleMask(), NSWindowStyleMask::Resizable) {
+        if self.window().styleMask().contains(NSWindowStyleMask::Resizable) {
             // Just use the native zoom if resizable
             self.window().zoom(None);
         } else {
@@ -1344,9 +1416,8 @@ impl WindowDelegate {
                 // set a normal style temporarily. The previous state will be
                 // restored in `WindowDelegate::window_did_exit_fullscreen`.
                 let curr_mask = self.window().styleMask();
-                let required =
-                    NSWindowStyleMask(NSWindowStyleMask::Titled.0 | NSWindowStyleMask::Resizable.0);
-                if !mask_contains(curr_mask, required) {
+                let required = NSWindowStyleMask::Titled | NSWindowStyleMask::Resizable;
+                if !curr_mask.contains(required) {
                     self.set_style_mask(required);
                     self.ivars().saved_style.set(Some(curr_mask));
                 }
@@ -1357,13 +1428,7 @@ impl WindowDelegate {
                 toggle_fullscreen(self.window());
             },
             (Some(Fullscreen::Exclusive(ref video_mode)), None) => {
-                unsafe {
-                    ffi::CGRestorePermanentDisplayConfiguration();
-                    assert_eq!(
-                        ffi::CGDisplayRelease(video_mode.monitor().native_identifier()),
-                        ffi::kCGErrorSuccess
-                    );
-                };
+                restore_and_release_display(&video_mode.monitor());
                 toggle_fullscreen(self.window());
             },
             (Some(Fullscreen::Borderless(_)), Some(Fullscreen::Exclusive(_))) => {
@@ -1377,11 +1442,10 @@ impl WindowDelegate {
                 // delegate in `window:willUseFullScreenPresentationOptions:`.
                 self.ivars().save_presentation_opts.set(Some(app.presentationOptions()));
 
-                let presentation_options = NSApplicationPresentationOptions(
-                    NSApplicationPresentationOptions::NSApplicationPresentationFullScreen.0
-                        | NSApplicationPresentationOptions::NSApplicationPresentationHideDock.0
-                        | NSApplicationPresentationOptions::NSApplicationPresentationHideMenuBar.0,
-                );
+                let presentation_options =
+                    NSApplicationPresentationOptions::NSApplicationPresentationFullScreen
+                        | NSApplicationPresentationOptions::NSApplicationPresentationHideDock
+                        | NSApplicationPresentationOptions::NSApplicationPresentationHideMenuBar;
                 app.setPresentationOptions(presentation_options);
 
                 let window_level = unsafe { ffi::CGShieldingWindowLevel() } as NSWindowLevel + 1;
@@ -1389,19 +1453,13 @@ impl WindowDelegate {
             },
             (Some(Fullscreen::Exclusive(ref video_mode)), Some(Fullscreen::Borderless(_))) => {
                 let presentation_options = self.ivars().save_presentation_opts.get().unwrap_or(
-                    NSApplicationPresentationOptions(NSApplicationPresentationOptions::NSApplicationPresentationFullScreen.0
-                        | NSApplicationPresentationOptions::NSApplicationPresentationAutoHideDock.0
-                        | NSApplicationPresentationOptions::NSApplicationPresentationAutoHideMenuBar.0),
+                    NSApplicationPresentationOptions::NSApplicationPresentationFullScreen
+                        | NSApplicationPresentationOptions::NSApplicationPresentationAutoHideDock
+                        | NSApplicationPresentationOptions::NSApplicationPresentationAutoHideMenuBar
                 );
                 app.setPresentationOptions(presentation_options);
 
-                unsafe {
-                    ffi::CGRestorePermanentDisplayConfiguration();
-                    assert_eq!(
-                        ffi::CGDisplayRelease(video_mode.monitor().native_identifier()),
-                        ffi::kCGErrorSuccess
-                    );
-                };
+                restore_and_release_display(&video_mode.monitor());
 
                 // Restore the normal window level following the Borderless fullscreen
                 // `CGShieldingWindowLevel() + 1` hack.
@@ -1430,19 +1488,19 @@ impl WindowDelegate {
 
         let new_mask = {
             let mut new_mask = if decorations {
-                NSWindowStyleMask::Closable.0
-                    | NSWindowStyleMask::Miniaturizable.0
-                    | NSWindowStyleMask::Resizable.0
-                    | NSWindowStyleMask::Titled.0
+                NSWindowStyleMask::Closable
+                    | NSWindowStyleMask::Miniaturizable
+                    | NSWindowStyleMask::Resizable
+                    | NSWindowStyleMask::Titled
             } else {
-                NSWindowStyleMask::Borderless.0 | NSWindowStyleMask::Resizable.0
+                NSWindowStyleMask::Borderless | NSWindowStyleMask::Resizable
             };
             if !resizable {
-                new_mask &= !NSWindowStyleMask::Resizable.0;
+                new_mask &= !NSWindowStyleMask::Resizable;
             }
             new_mask
         };
-        self.set_style_mask(NSWindowStyleMask(new_mask));
+        self.set_style_mask(new_mask);
     }
 
     #[inline]
@@ -1540,36 +1598,12 @@ impl WindowDelegate {
         Some(monitor)
     }
 
-    #[cfg(feature = "rwh_04")]
-    #[inline]
-    pub fn raw_window_handle_rwh_04(&self) -> rwh_04::RawWindowHandle {
-        let mut window_handle = rwh_04::AppKitHandle::empty();
-        window_handle.ns_window = self.window() as *const WinitWindow as *mut _;
-        window_handle.ns_view = Id::as_ptr(&self.contentView().unwrap()) as *mut _;
-        rwh_04::RawWindowHandle::AppKit(window_handle)
-    }
-
-    #[cfg(feature = "rwh_05")]
-    #[inline]
-    pub fn raw_window_handle_rwh_05(&self) -> rwh_05::RawWindowHandle {
-        let mut window_handle = rwh_05::AppKitWindowHandle::empty();
-        window_handle.ns_window = self.window() as *const WinitWindow as *mut _;
-        window_handle.ns_view = Id::as_ptr(&self.view()) as *mut _;
-        rwh_05::RawWindowHandle::AppKit(window_handle)
-    }
-
-    #[cfg(feature = "rwh_05")]
-    #[inline]
-    pub fn raw_display_handle_rwh_05(&self) -> rwh_05::RawDisplayHandle {
-        rwh_05::RawDisplayHandle::AppKit(rwh_05::AppKitDisplayHandle::empty())
-    }
-
     #[cfg(feature = "rwh_06")]
     #[inline]
     pub fn raw_window_handle_rwh_06(&self) -> rwh_06::RawWindowHandle {
         let window_handle = rwh_06::AppKitWindowHandle::new({
-            let ptr = Id::as_ptr(&self.view()) as *mut _;
-            std::ptr::NonNull::new(ptr).expect("Id<T> should never be null")
+            let ptr = Retained::as_ptr(&self.view()) as *mut _;
+            std::ptr::NonNull::new(ptr).expect("Retained<T> should never be null")
         });
         rwh_06::RawWindowHandle::AppKit(window_handle)
     }
@@ -1577,26 +1611,34 @@ impl WindowDelegate {
     fn toggle_style_mask(&self, mask: NSWindowStyleMask, on: bool) {
         let current_style_mask = self.window().styleMask();
         if on {
-            self.set_style_mask(NSWindowStyleMask(current_style_mask.0 | mask.0));
+            self.set_style_mask(current_style_mask | mask);
         } else {
-            self.set_style_mask(NSWindowStyleMask(current_style_mask.0 & (!mask.0)));
+            self.set_style_mask(current_style_mask & !mask);
         }
     }
 
-    #[inline]
-    pub fn theme(&self) -> Option<Theme> {
-        self.ivars().current_theme.get()
-    }
-
     #[inline]
     pub fn has_focus(&self) -> bool {
         self.window().isKeyWindow()
     }
 
+    pub fn theme(&self) -> Option<Theme> {
+        unsafe { self.window().appearance() }
+            .map(|appearance| appearance_to_theme(&appearance))
+            .or_else(|| {
+                let mtm = MainThreadMarker::from(self);
+                let app = NSApplication::sharedApplication(mtm);
+
+                if app.respondsToSelector(sel!(effectiveAppearance)) {
+                    Some(super::window_delegate::appearance_to_theme(&app.effectiveAppearance()))
+                } else {
+                    Some(Theme::Light)
+                }
+            })
+    }
+
     pub fn set_theme(&self, theme: Option<Theme>) {
-        let mtm = MainThreadMarker::from(self);
-        set_ns_theme(theme, mtm);
-        self.ivars().current_theme.set(theme.or_else(|| Some(get_ns_theme(mtm))));
+        unsafe { self.window().setAppearance(theme_to_appearance(theme).as_deref()) };
     }
 
     #[inline]
@@ -1617,6 +1659,21 @@ impl WindowDelegate {
     }
 }
 
+fn restore_and_release_display(monitor: &MonitorHandle) {
+    let available_monitors = monitor::available_monitors();
+    if available_monitors.contains(monitor) {
+        unsafe {
+            ffi::CGRestorePermanentDisplayConfiguration();
+            assert_eq!(ffi::CGDisplayRelease(monitor.native_identifier()), ffi::kCGErrorSuccess);
+        };
+    } else {
+        warn!(
+            monitor = monitor.name(),
+            "Tried to restore exclusive fullscreen on a monitor that is no longer available"
+        );
+    }
+}
+
 impl WindowExtMacOS for WindowDelegate {
     #[inline]
     fn simple_fullscreen(&self) -> bool {
@@ -1652,10 +1709,9 @@ impl WindowExtMacOS for WindowDelegate {
             self.ivars().is_simple_fullscreen.set(true);
 
             // Simulate pre-Lion fullscreen by hiding the dock and menu bar
-            let presentation_options = NSApplicationPresentationOptions(
-                NSApplicationPresentationOptions::NSApplicationPresentationAutoHideDock.0
-                    | NSApplicationPresentationOptions::NSApplicationPresentationAutoHideMenuBar.0,
-            );
+            let presentation_options =
+                NSApplicationPresentationOptions::NSApplicationPresentationAutoHideDock
+                    | NSApplicationPresentationOptions::NSApplicationPresentationAutoHideMenuBar;
             app.setPresentationOptions(presentation_options);
 
             // Hide the titlebar
@@ -1753,43 +1809,42 @@ impl WindowExtMacOS for WindowDelegate {
     }
 }
 
-fn mask_contains(mask: NSWindowStyleMask, value: NSWindowStyleMask) -> bool {
-    mask.0 & value.0 == value.0
-}
-
 const DEFAULT_STANDARD_FRAME: NSRect =
     NSRect::new(NSPoint::new(50.0, 50.0), NSSize::new(800.0, 600.0));
 
-pub(super) fn get_ns_theme(mtm: MainThreadMarker) -> Theme {
-    let app = NSApplication::sharedApplication(mtm);
-    let has_theme: bool = unsafe { msg_send![&app, respondsToSelector: sel!(effectiveAppearance)] };
-    if !has_theme {
-        return Theme::Light;
-    }
-    let appearance = app.effectiveAppearance();
-    let name = appearance
-        .bestMatchFromAppearancesWithNames(&NSArray::from_id_slice(&[
-            NSString::from_str("NSAppearanceNameAqua"),
-            NSString::from_str("NSAppearanceNameDarkAqua"),
-        ]))
-        .unwrap();
-    match &*name.to_string() {
-        "NSAppearanceNameDarkAqua" => Theme::Dark,
-        _ => Theme::Light,
+fn dark_appearance_name() -> &'static NSString {
+    // Don't use the static `NSAppearanceNameDarkAqua` to allow linking on macOS < 10.14
+    ns_string!("NSAppearanceNameDarkAqua")
+}
+
+pub fn appearance_to_theme(appearance: &NSAppearance) -> Theme {
+    let best_match = appearance.bestMatchFromAppearancesWithNames(&NSArray::from_id_slice(&[
+        unsafe { NSAppearanceNameAqua.copy() },
+        dark_appearance_name().copy(),
+    ]));
+    if let Some(best_match) = best_match {
+        if *best_match == *dark_appearance_name() {
+            Theme::Dark
+        } else {
+            Theme::Light
+        }
+    } else {
+        warn!(?appearance, "failed to determine the theme of the appearance");
+        // Default to light in this case
+        Theme::Light
     }
 }
 
-fn set_ns_theme(theme: Option<Theme>, mtm: MainThreadMarker) {
-    let app = NSApplication::sharedApplication(mtm);
-    let has_theme: bool = unsafe { msg_send![&app, respondsToSelector: sel!(effectiveAppearance)] };
-    if has_theme {
-        let appearance = theme.map(|t| {
-            let name = match t {
-                Theme::Dark => NSString::from_str("NSAppearanceNameDarkAqua"),
-                Theme::Light => NSString::from_str("NSAppearanceNameAqua"),
-            };
-            NSAppearance::appearanceNamed(&name).unwrap()
-        });
-        app.setAppearance(appearance.as_ref().map(|a| a.as_ref()));
+fn theme_to_appearance(theme: Option<Theme>) -> Option<Retained<NSAppearance>> {
+    let appearance = match theme? {
+        Theme::Light => unsafe { NSAppearance::appearanceNamed(NSAppearanceNameAqua) },
+        Theme::Dark => NSAppearance::appearanceNamed(dark_appearance_name()),
+    };
+    if let Some(appearance) = appearance {
+        Some(appearance)
+    } else {
+        warn!(?theme, "could not find appearance for theme");
+        // Assume system appearance in this case
+        None
     }
 }

src/platform_impl/apple/mod.rs

@@ -0,0 +1,11 @@
+//! Apple/Darwin-specific implementations
+
+#[cfg(target_os = "macos")]
+mod appkit;
+#[cfg(not(target_os = "macos"))]
+mod uikit;
+
+#[cfg(target_os = "macos")]
+pub use self::appkit::*;
+#[cfg(not(target_os = "macos"))]
+pub use self::uikit::*;

src/platform_impl/apple/uikit/app_delegate.rs

@@ -0,0 +1,60 @@
+use objc2::{declare_class, mutability, ClassType, DeclaredClass};
+use objc2_foundation::{MainThreadMarker, NSObject};
+use objc2_ui_kit::UIApplication;
+
+use super::app_state::{self, send_occluded_event_for_all_windows, EventWrapper};
+use crate::event::Event;
+
+declare_class!(
+    pub struct AppDelegate;
+
+    unsafe impl ClassType for AppDelegate {
+        type Super = NSObject;
+        type Mutability = mutability::InteriorMutable;
+        const NAME: &'static str = "WinitApplicationDelegate";
+    }
+
+    impl DeclaredClass for AppDelegate {}
+
+    // UIApplicationDelegate protocol
+    unsafe impl AppDelegate {
+        #[method(application:didFinishLaunchingWithOptions:)]
+        fn did_finish_launching(&self, _application: &UIApplication, _: *mut NSObject) -> bool {
+            app_state::did_finish_launching(MainThreadMarker::new().unwrap());
+            true
+        }
+
+        #[method(applicationDidBecomeActive:)]
+        fn did_become_active(&self, _application: &UIApplication) {
+            let mtm = MainThreadMarker::new().unwrap();
+            app_state::handle_nonuser_event(mtm, EventWrapper::StaticEvent(Event::Resumed))
+        }
+
+        #[method(applicationWillResignActive:)]
+        fn will_resign_active(&self, _application: &UIApplication) {
+            let mtm = MainThreadMarker::new().unwrap();
+            app_state::handle_nonuser_event(mtm, EventWrapper::StaticEvent(Event::Suspended))
+        }
+
+        #[method(applicationWillEnterForeground:)]
+        fn will_enter_foreground(&self, application: &UIApplication) {
+            send_occluded_event_for_all_windows(application, false);
+        }
+
+        #[method(applicationDidEnterBackground:)]
+        fn did_enter_background(&self, application: &UIApplication) {
+            send_occluded_event_for_all_windows(application, true);
+        }
+
+        #[method(applicationWillTerminate:)]
+        fn will_terminate(&self, application: &UIApplication) {
+            app_state::terminated(application);
+        }
+
+        #[method(applicationDidReceiveMemoryWarning:)]
+        fn did_receive_memory_warning(&self, _application: &UIApplication) {
+            let mtm = MainThreadMarker::new().unwrap();
+            app_state::handle_nonuser_event(mtm, EventWrapper::StaticEvent(Event::MemoryWarning))
+        }
+    }
+);

src/platform_impl/apple/uikit/app_state.rs

@@ -3,6 +3,7 @@
 use std::cell::{RefCell, RefMut};
 use std::collections::HashSet;
 use std::os::raw::c_void;
+use std::sync::atomic::AtomicBool;
 use std::sync::{Arc, Mutex, OnceLock};
 use std::time::Instant;
 use std::{fmt, mem, ptr};
@@ -13,15 +14,17 @@ use core_foundation::runloop::{
     kCFRunLoopCommonModes, CFRunLoopAddTimer, CFRunLoopGetMain, CFRunLoopRef, CFRunLoopTimerCreate,
     CFRunLoopTimerInvalidate, CFRunLoopTimerRef, CFRunLoopTimerSetNextFireDate,
 };
-use objc2::rc::Id;
+use objc2::rc::Retained;
 use objc2::runtime::AnyObject;
 use objc2::{msg_send, sel};
 use objc2_foundation::{
-    CGRect, CGSize, MainThreadMarker, NSInteger, NSOperatingSystemVersion, NSProcessInfo,
+    CGRect, CGSize, MainThreadMarker, NSInteger, NSObjectProtocol, NSOperatingSystemVersion,
+    NSProcessInfo,
 };
+use objc2_ui_kit::{UIApplication, UICoordinateSpace, UIView, UIWindow};
 
-use super::uikit::UIView;
 use super::window::WinitUIWindow;
+use super::ActiveEventLoop;
 use crate::dpi::PhysicalSize;
 use crate::event::{Event, InnerSizeWriter, StartCause, WindowEvent};
 use crate::event_loop::{ActiveEventLoop as RootActiveEventLoop, ControlFlow};
@@ -39,13 +42,10 @@ macro_rules! bug_assert {
     };
 }
 
-#[derive(Debug)]
-pub(crate) struct HandlePendingUserEvents;
-
 pub(crate) struct EventLoopHandler {
     #[allow(clippy::type_complexity)]
-    pub(crate) handler: Box<dyn FnMut(Event<HandlePendingUserEvents>, &RootActiveEventLoop)>,
-    pub(crate) event_loop: RootActiveEventLoop,
+    pub(crate) handler: Box<dyn FnMut(Event, &dyn RootActiveEventLoop)>,
+    pub(crate) event_loop: ActiveEventLoop,
 }
 
 impl fmt::Debug for EventLoopHandler {
@@ -58,20 +58,20 @@ impl fmt::Debug for EventLoopHandler {
 }
 
 impl EventLoopHandler {
-    fn handle_event(&mut self, event: Event<HandlePendingUserEvents>) {
+    fn handle_event(&mut self, event: Event) {
         (self.handler)(event, &self.event_loop)
     }
 }
 
 #[derive(Debug)]
 pub(crate) enum EventWrapper {
-    StaticEvent(Event<HandlePendingUserEvents>),
+    StaticEvent(Event),
     ScaleFactorChanged(ScaleFactorChanged),
 }
 
 #[derive(Debug)]
 pub struct ScaleFactorChanged {
-    pub(super) window: Id<WinitUIWindow>,
+    pub(super) window: Retained<WinitUIWindow>,
     pub(super) suggested_size: PhysicalSize<u32>,
     pub(super) scale_factor: f64,
 }
@@ -87,7 +87,7 @@ enum UserCallbackTransitionResult<'a> {
     },
 }
 
-impl Event<HandlePendingUserEvents> {
+impl Event {
     fn is_redraw(&self) -> bool {
         matches!(self, Event::WindowEvent { event: WindowEvent::RedrawRequested, .. })
     }
@@ -98,25 +98,25 @@ impl Event<HandlePendingUserEvents> {
 #[must_use = "dropping `AppStateImpl` without inspecting it is probably a bug"]
 enum AppStateImpl {
     NotLaunched {
-        queued_windows: Vec<Id<WinitUIWindow>>,
+        queued_windows: Vec<Retained<WinitUIWindow>>,
         queued_events: Vec<EventWrapper>,
-        queued_gpu_redraws: HashSet<Id<WinitUIWindow>>,
+        queued_gpu_redraws: HashSet<Retained<WinitUIWindow>>,
     },
     Launching {
-        queued_windows: Vec<Id<WinitUIWindow>>,
+        queued_windows: Vec<Retained<WinitUIWindow>>,
         queued_events: Vec<EventWrapper>,
         queued_handler: EventLoopHandler,
-        queued_gpu_redraws: HashSet<Id<WinitUIWindow>>,
+        queued_gpu_redraws: HashSet<Retained<WinitUIWindow>>,
     },
     ProcessingEvents {
         handler: EventLoopHandler,
-        queued_gpu_redraws: HashSet<Id<WinitUIWindow>>,
+        queued_gpu_redraws: HashSet<Retained<WinitUIWindow>>,
         active_control_flow: ControlFlow,
     },
     // special state to deal with reentrancy and prevent mutable aliasing.
     InUserCallback {
         queued_events: Vec<EventWrapper>,
-        queued_gpu_redraws: HashSet<Id<WinitUIWindow>>,
+        queued_gpu_redraws: HashSet<Retained<WinitUIWindow>>,
     },
     ProcessingRedraws {
         handler: EventLoopHandler,
@@ -137,6 +137,7 @@ pub(crate) struct AppState {
     app_state: Option<AppStateImpl>,
     control_flow: ControlFlow,
     waker: EventLoopWaker,
+    proxy_wake_up: Arc<AtomicBool>,
 }
 
 impl AppState {
@@ -160,6 +161,7 @@ impl AppState {
                     }),
                     control_flow: ControlFlow::default(),
                     waker,
+                    proxy_wake_up: Arc::new(AtomicBool::new(false)),
                 });
             }
             init_guard(&mut guard);
@@ -227,7 +229,9 @@ impl AppState {
         });
     }
 
-    fn did_finish_launching_transition(&mut self) -> (Vec<Id<WinitUIWindow>>, Vec<EventWrapper>) {
+    fn did_finish_launching_transition(
+        &mut self,
+    ) -> (Vec<Retained<WinitUIWindow>>, Vec<EventWrapper>) {
         let (windows, events, handler, queued_gpu_redraws) = match self.take_state() {
             AppStateImpl::Launching {
                 queued_windows,
@@ -343,7 +347,7 @@ impl AppState {
         UserCallbackTransitionResult::Success { handler, active_control_flow, processing_redraws }
     }
 
-    fn main_events_cleared_transition(&mut self) -> HashSet<Id<WinitUIWindow>> {
+    fn main_events_cleared_transition(&mut self) -> HashSet<Retained<WinitUIWindow>> {
         let (handler, queued_gpu_redraws, active_control_flow) = match self.take_state() {
             AppStateImpl::ProcessingEvents { handler, queued_gpu_redraws, active_control_flow } => {
                 (handler, queued_gpu_redraws, active_control_flow)
@@ -402,6 +406,10 @@ impl AppState {
         }
     }
 
+    pub(crate) fn proxy_wake_up(&self) -> Arc<AtomicBool> {
+        self.proxy_wake_up.clone()
+    }
+
     pub(crate) fn set_control_flow(&mut self, control_flow: ControlFlow) {
         self.control_flow = control_flow;
     }
@@ -411,7 +419,7 @@ impl AppState {
     }
 }
 
-pub(crate) fn set_key_window(mtm: MainThreadMarker, window: &Id<WinitUIWindow>) {
+pub(crate) fn set_key_window(mtm: MainThreadMarker, window: &Retained<WinitUIWindow>) {
     let mut this = AppState::get_mut(mtm);
     match this.state_mut() {
         &mut AppStateImpl::NotLaunched { ref mut queued_windows, .. } => {
@@ -431,7 +439,7 @@ pub(crate) fn set_key_window(mtm: MainThreadMarker, window: &Id<WinitUIWindow>)
     window.makeKeyAndVisible();
 }
 
-pub(crate) fn queue_gl_or_metal_redraw(mtm: MainThreadMarker, window: Id<WinitUIWindow>) {
+pub(crate) fn queue_gl_or_metal_redraw(mtm: MainThreadMarker, window: Retained<WinitUIWindow>) {
     let mut this = AppState::get_mut(mtm);
     match this.state_mut() {
         &mut AppStateImpl::NotLaunched { ref mut queued_gpu_redraws, .. }
@@ -489,8 +497,12 @@ pub fn did_finish_launching(mtm: MainThreadMarker) {
 
     let (windows, events) = AppState::get_mut(mtm).did_finish_launching_transition();
 
-    let events = std::iter::once(EventWrapper::StaticEvent(Event::NewEvents(StartCause::Init)))
-        .chain(events);
+    let events = [
+        EventWrapper::StaticEvent(Event::NewEvents(StartCause::Init)),
+        EventWrapper::StaticEvent(Event::CreateSurfaces),
+    ]
+    .into_iter()
+    .chain(events);
     handle_nonuser_events(mtm, events);
 
     // the above window dance hack, could possibly trigger new windows to be created.
@@ -622,7 +634,7 @@ fn handle_user_events(mtm: MainThreadMarker) {
     }
     drop(this);
 
-    handler.handle_event(Event::UserEvent(HandlePendingUserEvents));
+    handler.handle_event(Event::UserWakeUp);
 
     loop {
         let mut this = AppState::get_mut(mtm);
@@ -655,10 +667,32 @@ fn handle_user_events(mtm: MainThreadMarker) {
             }
         }
 
-        handler.handle_event(Event::UserEvent(HandlePendingUserEvents));
+        handler.handle_event(Event::UserWakeUp);
     }
 }
 
+pub(crate) fn send_occluded_event_for_all_windows(application: &UIApplication, occluded: bool) {
+    let mtm = MainThreadMarker::from(application);
+
+    let mut events = Vec::new();
+    #[allow(deprecated)]
+    for window in application.windows().iter() {
+        if window.is_kind_of::<WinitUIWindow>() {
+            // SAFETY: We just checked that the window is a `winit` window
+            let window = unsafe {
+                let ptr: *const UIWindow = window;
+                let ptr: *const WinitUIWindow = ptr.cast();
+                &*ptr
+            };
+            events.push(EventWrapper::StaticEvent(Event::WindowEvent {
+                window_id: RootWindowId(window.id()),
+                event: WindowEvent::Occluded(occluded),
+            }));
+        }
+    }
+    handle_nonuser_events(mtm, events);
+}
+
 pub fn handle_main_events_cleared(mtm: MainThreadMarker) {
     let mut this = AppState::get_mut(mtm);
     if !this.has_launched() || this.has_terminated() {
@@ -693,7 +727,27 @@ pub fn handle_events_cleared(mtm: MainThreadMarker) {
     AppState::get_mut(mtm).events_cleared_transition();
 }
 
-pub fn terminated(mtm: MainThreadMarker) {
+pub(crate) fn terminated(application: &UIApplication) {
+    let mtm = MainThreadMarker::from(application);
+
+    let mut events = Vec::new();
+    #[allow(deprecated)]
+    for window in application.windows().iter() {
+        if window.is_kind_of::<WinitUIWindow>() {
+            // SAFETY: We just checked that the window is a `winit` window
+            let window = unsafe {
+                let ptr: *const UIWindow = window;
+                let ptr: *const WinitUIWindow = ptr.cast();
+                &*ptr
+            };
+            events.push(EventWrapper::StaticEvent(Event::WindowEvent {
+                window_id: RootWindowId(window.id()),
+                event: WindowEvent::Destroyed,
+            }));
+        }
+    }
+    handle_nonuser_events(mtm, events);
+
     let mut this = AppState::get_mut(mtm);
     let mut handler = this.terminated_transition();
     drop(this);
@@ -721,7 +775,7 @@ fn handle_hidpi_proxy(handler: &mut EventLoopHandler, event: ScaleFactorChanged)
     view.setFrame(new_frame);
 }
 
-fn get_view_and_screen_frame(window: &WinitUIWindow) -> (Id<UIView>, CGRect) {
+fn get_view_and_screen_frame(window: &WinitUIWindow) -> (Retained<UIView>, CGRect) {
     let view_controller = window.rootViewController().unwrap();
     let view = view_controller.view().unwrap();
     let bounds = window.bounds();
@@ -753,7 +807,7 @@ impl EventLoopWaker {
             // future, but that gets changed to fire immediately in did_finish_launching
             let timer = CFRunLoopTimerCreate(
                 ptr::null_mut(),
-                std::f64::MAX,
+                f64::MAX,
                 0.000_000_1,
                 0,
                 0,
@@ -767,11 +821,11 @@ impl EventLoopWaker {
     }
 
     fn stop(&mut self) {
-        unsafe { CFRunLoopTimerSetNextFireDate(self.timer, std::f64::MAX) }
+        unsafe { CFRunLoopTimerSetNextFireDate(self.timer, f64::MAX) }
     }
 
     fn start(&mut self) {
-        unsafe { CFRunLoopTimerSetNextFireDate(self.timer, std::f64::MIN) }
+        unsafe { CFRunLoopTimerSetNextFireDate(self.timer, f64::MIN) }
     }
 
     fn start_at(&mut self, instant: Instant) {
@@ -857,23 +911,17 @@ fn meets_requirements(
 }
 
 fn get_version() -> NSOperatingSystemVersion {
-    unsafe {
-        let process_info = NSProcessInfo::processInfo();
-        let atleast_ios_8: bool = msg_send![
-            &process_info,
-            respondsToSelector: sel!(operatingSystemVersion)
-        ];
-        // winit requires atleast iOS 8 because no one has put the time into supporting earlier os
-        // versions. Older iOS versions are increasingly difficult to test. For example,
-        // Xcode 11 does not support debugging on devices with an iOS version of less than
-        // 8. Another example, in order to use an iOS simulator older than iOS 8, you must
-        // download an older version of Xcode (<9), and at least Xcode 7 has been tested to
-        // not even run on macOS 10.15 - Xcode 8 might?
-        //
-        // The minimum required iOS version is likely to grow in the future.
-        assert!(atleast_ios_8, "`winit` requires iOS version 8 or greater");
-        process_info.operatingSystemVersion()
-    }
+    let process_info = NSProcessInfo::processInfo();
+    let atleast_ios_8 = process_info.respondsToSelector(sel!(operatingSystemVersion));
+    // Winit requires atleast iOS 8 because no one has put the time into supporting earlier os
+    // versions. Older iOS versions are increasingly difficult to test. For example, Xcode 11 does
+    // not support debugging on devices with an iOS version of less than 8. Another example, in
+    // order to use an iOS simulator older than iOS 8, you must download an older version of Xcode
+    // (<9), and at least Xcode 7 has been tested to not even run on macOS 10.15 - Xcode 8 might?
+    //
+    // The minimum required iOS version is likely to grow in the future.
+    assert!(atleast_ios_8, "`winit` requires iOS version 8 or greater");
+    process_info.operatingSystemVersion()
 }
 
 pub fn os_capabilities() -> OSCapabilities {

src/platform_impl/apple/uikit/event_loop.rs

@@ -1,8 +1,8 @@
-use std::collections::VecDeque;
-use std::ffi::c_void;
-use std::marker::PhantomData;
-use std::ptr;
-use std::sync::mpsc::{self, Receiver, Sender};
+use std::any::Any;
+use std::ffi::{c_char, c_int, c_void};
+use std::ptr::{self, NonNull};
+use std::sync::atomic::{AtomicBool, Ordering as AtomicOrdering};
+use std::sync::Arc;
 
 use core_foundation::base::{CFIndex, CFRelease};
 use core_foundation::runloop::{
@@ -11,92 +11,111 @@ use core_foundation::runloop::{
     CFRunLoopObserverCreate, CFRunLoopObserverRef, CFRunLoopSourceContext, CFRunLoopSourceCreate,
     CFRunLoopSourceInvalidate, CFRunLoopSourceRef, CFRunLoopSourceSignal, CFRunLoopWakeUp,
 };
-use objc2::ClassType;
+use objc2::rc::Retained;
+use objc2::{msg_send_id, ClassType};
 use objc2_foundation::{MainThreadMarker, NSString};
-
-use crate::error::EventLoopError;
-use crate::event::Event;
-use crate::event_loop::{
-    ActiveEventLoop as RootActiveEventLoop, ControlFlow, DeviceEvents, EventLoopClosed,
-};
-use crate::platform::ios::Idiom;
-use crate::platform_impl::platform::app_state::{EventLoopHandler, HandlePendingUserEvents};
-use crate::window::{CustomCursor, CustomCursorSource};
+use objc2_ui_kit::{UIApplication, UIApplicationMain, UIScreen};
 
 use super::app_delegate::AppDelegate;
-use super::app_state::AppState;
-use super::uikit::{UIApplication, UIApplicationMain, UIDevice, UIScreen, UIUserInterfaceIdiom};
+use super::app_state::{AppState, EventLoopHandler};
 use super::{app_state, monitor, MonitorHandle};
+use crate::application::ApplicationHandler;
+use crate::error::{EventLoopError, ExternalError, NotSupportedError, OsError};
+use crate::event::Event;
+use crate::event_loop::{
+    ActiveEventLoop as RootActiveEventLoop, ControlFlow, DeviceEvents,
+    EventLoopProxy as RootEventLoopProxy, OwnedDisplayHandle as RootOwnedDisplayHandle,
+};
+use crate::monitor::MonitorHandle as RootMonitorHandle;
+use crate::platform_impl::Window;
+use crate::window::{CustomCursor, CustomCursorSource, Theme, Window as RootWindow};
 
 #[derive(Debug)]
-pub struct ActiveEventLoop {
+pub(crate) struct ActiveEventLoop {
     pub(super) mtm: MainThreadMarker,
 }
 
-impl ActiveEventLoop {
-    pub fn create_custom_cursor(&self, source: CustomCursorSource) -> CustomCursor {
-        let _ = source.inner;
-        CustomCursor { inner: super::PlatformCustomCursor }
+impl RootActiveEventLoop for ActiveEventLoop {
+    fn create_proxy(&self) -> crate::event_loop::EventLoopProxy {
+        let event_loop_proxy = EventLoopProxy::new(AppState::get_mut(self.mtm).proxy_wake_up());
+        RootEventLoopProxy { event_loop_proxy }
     }
 
-    pub fn available_monitors(&self) -> VecDeque<MonitorHandle> {
-        monitor::uiscreens(self.mtm)
-    }
-
-    pub fn primary_monitor(&self) -> Option<MonitorHandle> {
-        Some(MonitorHandle::new(UIScreen::main(self.mtm)))
-    }
-
-    #[inline]
-    pub fn listen_device_events(&self, _allowed: DeviceEvents) {}
-
-    #[cfg(feature = "rwh_05")]
-    #[inline]
-    pub fn raw_display_handle_rwh_05(&self) -> rwh_05::RawDisplayHandle {
-        rwh_05::RawDisplayHandle::UiKit(rwh_05::UiKitDisplayHandle::empty())
-    }
-
-    #[cfg(feature = "rwh_06")]
-    #[inline]
-    pub fn raw_display_handle_rwh_06(
+    fn create_window(
         &self,
-    ) -> Result<rwh_06::RawDisplayHandle, rwh_06::HandleError> {
-        Ok(rwh_06::RawDisplayHandle::UiKit(rwh_06::UiKitDisplayHandle::new()))
+        window_attributes: crate::window::WindowAttributes,
+    ) -> Result<RootWindow, OsError> {
+        let window = Window::new(self, window_attributes)?;
+        Ok(RootWindow { window })
     }
 
-    pub(crate) fn set_control_flow(&self, control_flow: ControlFlow) {
+    fn create_custom_cursor(
+        &self,
+        _source: CustomCursorSource,
+    ) -> Result<CustomCursor, ExternalError> {
+        Err(ExternalError::NotSupported(NotSupportedError::new()))
+    }
+
+    fn available_monitors(&self) -> Box<dyn Iterator<Item = RootMonitorHandle>> {
+        Box::new(monitor::uiscreens(self.mtm).into_iter().map(|inner| RootMonitorHandle { inner }))
+    }
+
+    fn primary_monitor(&self) -> Option<crate::monitor::MonitorHandle> {
+        #[allow(deprecated)]
+        let monitor = MonitorHandle::new(UIScreen::mainScreen(self.mtm));
+        Some(RootMonitorHandle { inner: monitor })
+    }
+
+    fn listen_device_events(&self, _allowed: DeviceEvents) {}
+
+    fn set_control_flow(&self, control_flow: ControlFlow) {
         AppState::get_mut(self.mtm).set_control_flow(control_flow)
     }
 
-    pub(crate) fn control_flow(&self) -> ControlFlow {
+    fn system_theme(&self) -> Option<Theme> {
+        None
+    }
+
+    fn control_flow(&self) -> ControlFlow {
         AppState::get_mut(self.mtm).control_flow()
     }
 
-    pub(crate) fn exit(&self) {
+    fn exit(&self) {
         // https://developer.apple.com/library/archive/qa/qa1561/_index.html
         // it is not possible to quit an iOS app gracefully and programmatically
         tracing::warn!("`ControlFlow::Exit` ignored on iOS");
     }
 
-    pub(crate) fn exiting(&self) -> bool {
+    fn exiting(&self) -> bool {
         false
     }
 
-    pub(crate) fn owned_display_handle(&self) -> OwnedDisplayHandle {
-        OwnedDisplayHandle
+    fn owned_display_handle(&self) -> RootOwnedDisplayHandle {
+        RootOwnedDisplayHandle { platform: OwnedDisplayHandle }
+    }
+
+    fn as_any(&self) -> &dyn Any {
+        self
+    }
+
+    #[cfg(feature = "rwh_06")]
+    fn rwh_06_handle(&self) -> &dyn rwh_06::HasDisplayHandle {
+        self
     }
 }
 
-#[derive(Clone)]
+#[cfg(feature = "rwh_06")]
+impl rwh_06::HasDisplayHandle for ActiveEventLoop {
+    fn display_handle(&self) -> Result<rwh_06::DisplayHandle<'_>, rwh_06::HandleError> {
+        let raw = rwh_06::RawDisplayHandle::UiKit(rwh_06::UiKitDisplayHandle::new());
+        unsafe { Ok(rwh_06::DisplayHandle::borrow_raw(raw)) }
+    }
+}
+
+#[derive(Clone, PartialEq, Eq)]
 pub(crate) struct OwnedDisplayHandle;
 
 impl OwnedDisplayHandle {
-    #[cfg(feature = "rwh_05")]
-    #[inline]
-    pub fn raw_display_handle_rwh_05(&self) -> rwh_05::RawDisplayHandle {
-        rwh_05::UiKitDisplayHandle::empty().into()
-    }
-
     #[cfg(feature = "rwh_06")]
     #[inline]
     pub fn raw_display_handle_rwh_06(
@@ -106,34 +125,44 @@ impl OwnedDisplayHandle {
     }
 }
 
-fn map_user_event<T: 'static>(
-    mut handler: impl FnMut(Event<T>, &RootActiveEventLoop),
-    receiver: mpsc::Receiver<T>,
-) -> impl FnMut(Event<HandlePendingUserEvents>, &RootActiveEventLoop) {
-    move |event, window_target| match event.map_nonuser_event() {
-        Ok(event) => (handler)(event, window_target),
-        Err(_) => {
-            for event in receiver.try_iter() {
-                (handler)(Event::UserEvent(event), window_target);
+fn map_user_event<'a, A: ApplicationHandler + 'a>(
+    mut app: A,
+    proxy_wake_up: Arc<AtomicBool>,
+) -> impl FnMut(Event, &dyn RootActiveEventLoop) + 'a {
+    move |event, window_target| match event {
+        Event::NewEvents(cause) => app.new_events(window_target, cause),
+        Event::WindowEvent { window_id, event } => {
+            app.window_event(window_target, window_id, event)
+        },
+        Event::DeviceEvent { device_id, event } => {
+            app.device_event(window_target, device_id, event)
+        },
+        Event::UserWakeUp => {
+            if proxy_wake_up.swap(false, AtomicOrdering::Relaxed) {
+                app.proxy_wake_up(window_target);
             }
         },
+        Event::Suspended => app.suspended(window_target),
+        Event::Resumed => app.resumed(window_target),
+        Event::CreateSurfaces => app.can_create_surfaces(window_target),
+        Event::AboutToWait => app.about_to_wait(window_target),
+        Event::LoopExiting => app.exiting(window_target),
+        Event::MemoryWarning => app.memory_warning(window_target),
     }
 }
 
-pub struct EventLoop<T: 'static> {
+pub struct EventLoop {
     mtm: MainThreadMarker,
-    sender: Sender<T>,
-    receiver: Receiver<T>,
-    window_target: RootActiveEventLoop,
+    window_target: ActiveEventLoop,
 }
 
 #[derive(Default, Debug, Copy, Clone, PartialEq, Eq, Hash)]
 pub(crate) struct PlatformSpecificEventLoopAttributes {}
 
-impl<T: 'static> EventLoop<T> {
+impl EventLoop {
     pub(crate) fn new(
         _: &PlatformSpecificEventLoopAttributes,
-    ) -> Result<EventLoop<T>, EventLoopError> {
+    ) -> Result<EventLoop, EventLoopError> {
         let mtm = MainThreadMarker::new()
             .expect("On iOS, `EventLoop` must be created on the main thread");
 
@@ -146,24 +175,15 @@ impl<T: 'static> EventLoop<T> {
             SINGLETON_INIT = true;
         }
 
-        let (sender, receiver) = mpsc::channel();
-
         // this line sets up the main run loop before `UIApplicationMain`
         setup_control_flow_observers();
 
-        Ok(EventLoop {
-            mtm,
-            sender,
-            receiver,
-            window_target: RootActiveEventLoop { p: ActiveEventLoop { mtm }, _marker: PhantomData },
-        })
+        Ok(EventLoop { mtm, window_target: ActiveEventLoop { mtm } })
     }
 
-    pub fn run<F>(self, handler: F) -> !
-    where
-        F: FnMut(Event<T>, &RootActiveEventLoop),
-    {
-        let application = UIApplication::shared(self.mtm);
+    pub fn run_app<A: ApplicationHandler>(self, app: A) -> ! {
+        let application: Option<Retained<UIApplication>> =
+            unsafe { msg_send_id![UIApplication::class(), sharedApplication] };
         assert!(
             application.is_none(),
             "\
@@ -171,12 +191,12 @@ impl<T: 'static> EventLoop<T> {
              `EventLoop::run_app` calls `UIApplicationMain` on iOS",
         );
 
-        let handler = map_user_event(handler, self.receiver);
+        let handler = map_user_event(app, AppState::get_mut(self.mtm).proxy_wake_up());
 
         let handler = unsafe {
             std::mem::transmute::<
-                Box<dyn FnMut(Event<HandlePendingUserEvents>, &RootActiveEventLoop)>,
-                Box<dyn FnMut(Event<HandlePendingUserEvents>, &RootActiveEventLoop)>,
+                Box<dyn FnMut(Event, &dyn RootActiveEventLoop)>,
+                Box<dyn FnMut(Event, &dyn RootActiveEventLoop)>,
             >(Box::new(handler))
         };
 
@@ -187,50 +207,43 @@ impl<T: 'static> EventLoop<T> {
         // Ensure application delegate is initialized
         let _ = AppDelegate::class();
 
+        extern "C" {
+            // These functions are in crt_externs.h.
+            fn _NSGetArgc() -> *mut c_int;
+            fn _NSGetArgv() -> *mut *mut *mut c_char;
+        }
+
         unsafe {
-            UIApplicationMain(0, ptr::null(), None, Some(&NSString::from_str(AppDelegate::NAME)))
+            UIApplicationMain(
+                *_NSGetArgc(),
+                NonNull::new(*_NSGetArgv()).unwrap(),
+                None,
+                Some(&NSString::from_str(AppDelegate::NAME)),
+            )
         };
         unreachable!()
     }
 
-    pub fn create_proxy(&self) -> EventLoopProxy<T> {
-        EventLoopProxy::new(self.sender.clone())
-    }
-
-    pub fn window_target(&self) -> &RootActiveEventLoop {
+    pub fn window_target(&self) -> &dyn RootActiveEventLoop {
         &self.window_target
     }
 }
 
-// EventLoopExtIOS
-impl<T: 'static> EventLoop<T> {
-    pub fn idiom(&self) -> Idiom {
-        match UIDevice::current(self.mtm).userInterfaceIdiom() {
-            UIUserInterfaceIdiom::Unspecified => Idiom::Unspecified,
-            UIUserInterfaceIdiom::Phone => Idiom::Phone,
-            UIUserInterfaceIdiom::Pad => Idiom::Pad,
-            UIUserInterfaceIdiom::TV => Idiom::TV,
-            UIUserInterfaceIdiom::CarPlay => Idiom::CarPlay,
-            _ => Idiom::Unspecified,
-        }
-    }
-}
-
-pub struct EventLoopProxy<T> {
-    sender: Sender<T>,
+pub struct EventLoopProxy {
+    proxy_wake_up: Arc<AtomicBool>,
     source: CFRunLoopSourceRef,
 }
 
-unsafe impl<T: Send> Send for EventLoopProxy<T> {}
-unsafe impl<T: Send> Sync for EventLoopProxy<T> {}
+unsafe impl Send for EventLoopProxy {}
+unsafe impl Sync for EventLoopProxy {}
 
-impl<T> Clone for EventLoopProxy<T> {
-    fn clone(&self) -> EventLoopProxy<T> {
-        EventLoopProxy::new(self.sender.clone())
+impl Clone for EventLoopProxy {
+    fn clone(&self) -> EventLoopProxy {
+        EventLoopProxy::new(self.proxy_wake_up.clone())
     }
 }
 
-impl<T> Drop for EventLoopProxy<T> {
+impl Drop for EventLoopProxy {
     fn drop(&mut self) {
         unsafe {
             CFRunLoopSourceInvalidate(self.source);
@@ -239,8 +252,8 @@ impl<T> Drop for EventLoopProxy<T> {
     }
 }
 
-impl<T> EventLoopProxy<T> {
-    fn new(sender: Sender<T>) -> EventLoopProxy<T> {
+impl EventLoopProxy {
+    fn new(proxy_wake_up: Arc<AtomicBool>) -> EventLoopProxy {
         unsafe {
             // just wake up the eventloop
             extern "C" fn event_loop_proxy_handler(_: *const c_void) {}
@@ -260,24 +273,22 @@ impl<T> EventLoopProxy<T> {
                 cancel: None,
                 perform: event_loop_proxy_handler,
             };
-            let source =
-                CFRunLoopSourceCreate(ptr::null_mut(), CFIndex::max_value() - 1, &mut context);
+            let source = CFRunLoopSourceCreate(ptr::null_mut(), CFIndex::MAX - 1, &mut context);
             CFRunLoopAddSource(rl, source, kCFRunLoopCommonModes);
             CFRunLoopWakeUp(rl);
 
-            EventLoopProxy { sender, source }
+            EventLoopProxy { proxy_wake_up, source }
         }
     }
 
-    pub fn send_event(&self, event: T) -> Result<(), EventLoopClosed<T>> {
-        self.sender.send(event).map_err(|::std::sync::mpsc::SendError(x)| EventLoopClosed(x))?;
+    pub fn wake_up(&self) {
+        self.proxy_wake_up.store(true, AtomicOrdering::Relaxed);
         unsafe {
             // let the main thread know there's a new event
             CFRunLoopSourceSignal(self.source);
             let rl = CFRunLoopGetMain();
             CFRunLoopWakeUp(rl);
         }
-        Ok(())
     }
 }
 
@@ -344,7 +355,7 @@ fn setup_control_flow_observers() {
             ptr::null_mut(),
             kCFRunLoopAfterWaiting,
             1, // repeat = true
-            CFIndex::min_value(),
+            CFIndex::MIN,
             control_flow_begin_handler,
             ptr::null_mut(),
         );
@@ -364,7 +375,7 @@ fn setup_control_flow_observers() {
             ptr::null_mut(),
             kCFRunLoopExit | kCFRunLoopBeforeWaiting,
             1, // repeat = true
-            CFIndex::max_value(),
+            CFIndex::MAX,
             control_flow_end_handler,
             ptr::null_mut(),
         );

src/platform_impl/apple/uikit/mod.rs

@@ -1,19 +1,15 @@
-#![cfg(ios_platform)]
 #![allow(clippy::let_unit_value)]
 
 mod app_delegate;
 mod app_state;
 mod event_loop;
 mod monitor;
-mod uikit;
 mod view;
 mod view_controller;
 mod window;
 
 use std::fmt;
 
-use crate::event::DeviceId as RootDeviceId;
-
 pub(crate) use self::event_loop::{
     ActiveEventLoop, EventLoop, EventLoopProxy, OwnedDisplayHandle,
     PlatformSpecificEventLoopAttributes,
@@ -23,6 +19,7 @@ pub(crate) use self::window::{PlatformSpecificWindowAttributes, Window, WindowId
 pub(crate) use crate::cursor::{
     NoCustomCursor as PlatformCustomCursor, NoCustomCursor as PlatformCustomCursorSource,
 };
+use crate::event::DeviceId as RootDeviceId;
 pub(crate) use crate::icon::NoIcon as PlatformIcon;
 pub(crate) use crate::platform_impl::Fullscreen;
 
@@ -34,13 +31,22 @@ pub(crate) use crate::platform_impl::Fullscreen;
 pub struct DeviceId;
 
 impl DeviceId {
-    pub const unsafe fn dummy() -> Self {
+    pub const fn dummy() -> Self {
         DeviceId
     }
 }
 
 pub(crate) const DEVICE_ID: RootDeviceId = RootDeviceId(DeviceId);
 
+#[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub struct FingerId(usize);
+
+impl FingerId {
+    pub const fn dummy() -> Self {
+        FingerId(0)
+    }
+}
+
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub struct KeyEventExtra {}
 

src/platform_impl/apple/uikit/monitor.rs

@@ -1,25 +1,26 @@
 #![allow(clippy::unnecessary_cast)]
 
 use std::collections::{BTreeSet, VecDeque};
+use std::num::{NonZeroU16, NonZeroU32};
 use std::{fmt, hash, ptr};
 
 use objc2::mutability::IsRetainable;
-use objc2::rc::Id;
+use objc2::rc::Retained;
 use objc2::Message;
 use objc2_foundation::{run_on_main, MainThreadBound, MainThreadMarker, NSInteger};
+use objc2_ui_kit::{UIScreen, UIScreenMode};
 
-use super::uikit::{UIScreen, UIScreenMode};
+use super::app_state;
 use crate::dpi::{PhysicalPosition, PhysicalSize};
 use crate::monitor::VideoModeHandle as RootVideoModeHandle;
-use crate::platform_impl::platform::app_state;
 
 // Workaround for `MainThreadBound` implementing almost no traits
 #[derive(Debug)]
-struct MainThreadBoundDelegateImpls<T>(MainThreadBound<Id<T>>);
+struct MainThreadBoundDelegateImpls<T>(MainThreadBound<Retained<T>>);
 
 impl<T: IsRetainable + Message> Clone for MainThreadBoundDelegateImpls<T> {
     fn clone(&self) -> Self {
-        Self(run_on_main(|mtm| MainThreadBound::new(Id::clone(self.0.get(mtm)), mtm)))
+        Self(run_on_main(|mtm| MainThreadBound::new(Retained::clone(self.0.get(mtm)), mtm)))
     }
 }
 
@@ -27,7 +28,7 @@ impl<T: IsRetainable + Message> hash::Hash for MainThreadBoundDelegateImpls<T> {
     fn hash<H: hash::Hasher>(&self, state: &mut H) {
         // SAFETY: Marker only used to get the pointer
         let mtm = unsafe { MainThreadMarker::new_unchecked() };
-        Id::as_ptr(self.0.get(mtm)).hash(state);
+        Retained::as_ptr(self.0.get(mtm)).hash(state);
     }
 }
 
@@ -35,7 +36,7 @@ impl<T: IsRetainable + Message> PartialEq for MainThreadBoundDelegateImpls<T> {
     fn eq(&self, other: &Self) -> bool {
         // SAFETY: Marker only used to get the pointer
         let mtm = unsafe { MainThreadMarker::new_unchecked() };
-        Id::as_ptr(self.0.get(mtm)) == Id::as_ptr(other.0.get(mtm))
+        Retained::as_ptr(self.0.get(mtm)) == Retained::as_ptr(other.0.get(mtm))
     }
 }
 
@@ -44,23 +45,21 @@ impl<T: IsRetainable + Message> Eq for MainThreadBoundDelegateImpls<T> {}
 #[derive(Debug, PartialEq, Eq, Hash, Clone)]
 pub struct VideoModeHandle {
     pub(crate) size: (u32, u32),
-    pub(crate) bit_depth: u16,
-    pub(crate) refresh_rate_millihertz: u32,
+    pub(crate) refresh_rate_millihertz: Option<NonZeroU32>,
     screen_mode: MainThreadBoundDelegateImpls<UIScreenMode>,
     pub(crate) monitor: MonitorHandle,
 }
 
 impl VideoModeHandle {
     fn new(
-        uiscreen: Id<UIScreen>,
-        screen_mode: Id<UIScreenMode>,
+        uiscreen: Retained<UIScreen>,
+        screen_mode: Retained<UIScreenMode>,
         mtm: MainThreadMarker,
     ) -> VideoModeHandle {
         let refresh_rate_millihertz = refresh_rate_millihertz(&uiscreen);
         let size = screen_mode.size();
         VideoModeHandle {
             size: (size.width as u32, size.height as u32),
-            bit_depth: 32,
             refresh_rate_millihertz,
             screen_mode: MainThreadBoundDelegateImpls(MainThreadBound::new(screen_mode, mtm)),
             monitor: MonitorHandle::new(uiscreen),
@@ -71,11 +70,11 @@ impl VideoModeHandle {
         self.size.into()
     }
 
-    pub fn bit_depth(&self) -> u16 {
-        self.bit_depth
+    pub fn bit_depth(&self) -> Option<NonZeroU16> {
+        None
     }
 
-    pub fn refresh_rate_millihertz(&self) -> u32 {
+    pub fn refresh_rate_millihertz(&self) -> Option<NonZeroU32> {
         self.refresh_rate_millihertz
     }
 
@@ -83,13 +82,13 @@ impl VideoModeHandle {
         self.monitor.clone()
     }
 
-    pub(super) fn screen_mode(&self, mtm: MainThreadMarker) -> &Id<UIScreenMode> {
+    pub(super) fn screen_mode(&self, mtm: MainThreadMarker) -> &Retained<UIScreenMode> {
         self.screen_mode.0.get(mtm)
     }
 }
 
 pub struct MonitorHandle {
-    ui_screen: MainThreadBound<Id<UIScreen>>,
+    ui_screen: MainThreadBound<Retained<UIScreen>>,
 }
 
 impl Clone for MonitorHandle {
@@ -131,29 +130,29 @@ impl fmt::Debug for MonitorHandle {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         f.debug_struct("MonitorHandle")
             .field("name", &self.name())
-            .field("size", &self.size())
             .field("position", &self.position())
             .field("scale_factor", &self.scale_factor())
-            .field("refresh_rate_millihertz", &self.refresh_rate_millihertz())
             .finish_non_exhaustive()
     }
 }
 
 impl MonitorHandle {
-    pub(crate) fn new(ui_screen: Id<UIScreen>) -> Self {
-        // Holding `Id<UIScreen>` implies we're on the main thread.
+    pub(crate) fn new(ui_screen: Retained<UIScreen>) -> Self {
+        // Holding `Retained<UIScreen>` implies we're on the main thread.
         let mtm = MainThreadMarker::new().unwrap();
         Self { ui_screen: MainThreadBound::new(ui_screen, mtm) }
     }
 
     pub fn name(&self) -> Option<String> {
         run_on_main(|mtm| {
-            let main = UIScreen::main(mtm);
+            #[allow(deprecated)]
+            let main = UIScreen::mainScreen(mtm);
             if *self.ui_screen(mtm) == main {
                 Some("Primary".to_string())
-            } else if *self.ui_screen(mtm) == main.mirroredScreen() {
+            } else if Some(self.ui_screen(mtm)) == main.mirroredScreen().as_ref() {
                 Some("Mirrored".to_string())
             } else {
+                #[allow(deprecated)]
                 UIScreen::screens(mtm)
                     .iter()
                     .position(|rhs| rhs == &**self.ui_screen(mtm))
@@ -162,22 +161,23 @@ impl MonitorHandle {
         })
     }
 
-    pub fn size(&self) -> PhysicalSize<u32> {
+    pub fn position(&self) -> Option<PhysicalPosition<i32>> {
         let bounds = self.ui_screen.get_on_main(|ui_screen| ui_screen.nativeBounds());
-        PhysicalSize::new(bounds.size.width as u32, bounds.size.height as u32)
-    }
-
-    pub fn position(&self) -> PhysicalPosition<i32> {
-        let bounds = self.ui_screen.get_on_main(|ui_screen| ui_screen.nativeBounds());
-        (bounds.origin.x as f64, bounds.origin.y as f64).into()
+        Some((bounds.origin.x as f64, bounds.origin.y as f64).into())
     }
 
     pub fn scale_factor(&self) -> f64 {
         self.ui_screen.get_on_main(|ui_screen| ui_screen.nativeScale()) as f64
     }
 
-    pub fn refresh_rate_millihertz(&self) -> Option<u32> {
-        Some(self.ui_screen.get_on_main(|ui_screen| refresh_rate_millihertz(ui_screen)))
+    pub fn current_video_mode(&self) -> Option<VideoModeHandle> {
+        Some(run_on_main(|mtm| {
+            VideoModeHandle::new(
+                self.ui_screen(mtm).clone(),
+                self.ui_screen(mtm).currentMode().unwrap(),
+                mtm,
+            )
+        }))
     }
 
     pub fn video_modes(&self) -> impl Iterator<Item = VideoModeHandle> {
@@ -197,7 +197,7 @@ impl MonitorHandle {
         })
     }
 
-    pub(crate) fn ui_screen(&self, mtm: MainThreadMarker) -> &Id<UIScreen> {
+    pub(crate) fn ui_screen(&self, mtm: MainThreadMarker) -> &Retained<UIScreen> {
         self.ui_screen.get(mtm)
     }
 
@@ -212,7 +212,7 @@ impl MonitorHandle {
     }
 }
 
-fn refresh_rate_millihertz(uiscreen: &UIScreen) -> u32 {
+fn refresh_rate_millihertz(uiscreen: &UIScreen) -> Option<NonZeroU32> {
     let refresh_rate_millihertz: NSInteger = {
         let os_capabilities = app_state::os_capabilities();
         if os_capabilities.maximum_frames_per_second {
@@ -233,9 +233,10 @@ fn refresh_rate_millihertz(uiscreen: &UIScreen) -> u32 {
         }
     };
 
-    refresh_rate_millihertz as u32 * 1000
+    NonZeroU32::new(refresh_rate_millihertz as u32 * 1000)
 }
 
 pub fn uiscreens(mtm: MainThreadMarker) -> VecDeque<MonitorHandle> {
+    #[allow(deprecated)]
     UIScreen::screens(mtm).into_iter().map(MonitorHandle::new).collect()
 }

src/platform_impl/apple/uikit/view.rs

@@ -1,31 +1,29 @@
 #![allow(clippy::unnecessary_cast)]
 use std::cell::{Cell, RefCell};
 
-use objc2::rc::Id;
-use objc2::runtime::{AnyClass, NSObjectProtocol, ProtocolObject};
-use objc2::{
-    declare_class, extern_methods, msg_send, msg_send_id, mutability, sel, ClassType, DeclaredClass,
-};
+use objc2::rc::Retained;
+use objc2::runtime::{NSObjectProtocol, ProtocolObject};
+use objc2::{declare_class, msg_send, msg_send_id, mutability, sel, ClassType, DeclaredClass};
 use objc2_foundation::{CGFloat, CGPoint, CGRect, MainThreadMarker, NSObject, NSSet};
+use objc2_ui_kit::{
+    UICoordinateSpace, UIEvent, UIForceTouchCapability, UIGestureRecognizer,
+    UIGestureRecognizerDelegate, UIGestureRecognizerState, UIPanGestureRecognizer,
+    UIPinchGestureRecognizer, UIResponder, UIRotationGestureRecognizer, UITapGestureRecognizer,
+    UITouch, UITouchPhase, UITouchType, UITraitEnvironment, UIView,
+};
 
 use super::app_state::{self, EventWrapper};
-use super::uikit::{
-    UIEvent, UIForceTouchCapability, UIGestureRecognizer, UIGestureRecognizerDelegate,
-    UIGestureRecognizerState, UIPanGestureRecognizer, UIPinchGestureRecognizer, UIResponder,
-    UIRotationGestureRecognizer, UITapGestureRecognizer, UITouch, UITouchPhase, UITouchType,
-    UITraitCollection, UIView,
-};
 use super::window::WinitUIWindow;
+use super::{FingerId, DEVICE_ID};
 use crate::dpi::PhysicalPosition;
-use crate::event::{Event, Force, Touch, TouchPhase, WindowEvent};
-use crate::platform_impl::platform::DEVICE_ID;
+use crate::event::{Event, FingerId as RootFingerId, Force, Touch, TouchPhase, WindowEvent};
 use crate::window::{WindowAttributes, WindowId as RootWindowId};
 
 pub struct WinitViewState {
-    pinch_gesture_recognizer: RefCell<Option<Id<UIPinchGestureRecognizer>>>,
-    doubletap_gesture_recognizer: RefCell<Option<Id<UITapGestureRecognizer>>>,
-    rotation_gesture_recognizer: RefCell<Option<Id<UIRotationGestureRecognizer>>>,
-    pan_gesture_recognizer: RefCell<Option<Id<UIPanGestureRecognizer>>>,
+    pinch_gesture_recognizer: RefCell<Option<Retained<UIPinchGestureRecognizer>>>,
+    doubletap_gesture_recognizer: RefCell<Option<Retained<UITapGestureRecognizer>>>,
+    rotation_gesture_recognizer: RefCell<Option<Retained<UIRotationGestureRecognizer>>>,
+    pan_gesture_recognizer: RefCell<Option<Retained<UIPanGestureRecognizer>>>,
 
     // for iOS delta references the start of the Gesture
     rotation_last_delta: Cell<CGFloat>,
@@ -39,7 +37,7 @@ declare_class!(
     unsafe impl ClassType for WinitView {
         #[inherits(UIResponder, NSObject)]
         type Super = UIView;
-        type Mutability = mutability::InteriorMutable;
+        type Mutability = mutability::MainThreadOnly;
         const NAME: &'static str = "WinitUIView";
     }
 
@@ -270,7 +268,7 @@ declare_class!(
         fn pan_gesture(&self, recognizer: &UIPanGestureRecognizer) {
             let window = self.window().unwrap();
 
-            let translation = recognizer.translationInView(self);
+            let translation = recognizer.translationInView(Some(self));
 
             let (phase, dx, dy) = match recognizer.state() {
                 UIGestureRecognizerState::Began => {
@@ -328,30 +326,13 @@ declare_class!(
     }
 );
 
-extern_methods!(
-    #[allow(non_snake_case)]
-    unsafe impl WinitView {
-        fn window(&self) -> Option<Id<WinitUIWindow>> {
-            unsafe { msg_send_id![self, window] }
-        }
-
-        unsafe fn traitCollection(&self) -> Id<UITraitCollection> {
-            msg_send_id![self, traitCollection]
-        }
-
-        // TODO: Allow the user to customize this
-        #[method(layerClass)]
-        pub(crate) fn layerClass() -> &'static AnyClass;
-    }
-);
-
 impl WinitView {
     pub(crate) fn new(
-        _mtm: MainThreadMarker,
+        mtm: MainThreadMarker,
         window_attributes: &WindowAttributes,
         frame: CGRect,
-    ) -> Id<Self> {
-        let this = Self::alloc().set_ivars(WinitViewState {
+    ) -> Retained<Self> {
+        let this = mtm.alloc().set_ivars(WinitViewState {
             pinch_gesture_recognizer: RefCell::new(None),
             doubletap_gesture_recognizer: RefCell::new(None),
             rotation_gesture_recognizer: RefCell::new(None),
@@ -361,7 +342,7 @@ impl WinitView {
             pinch_last_delta: Cell::new(0.0),
             pan_last_delta: Cell::new(CGPoint { x: 0.0, y: 0.0 }),
         });
-        let this: Id<Self> = unsafe { msg_send_id![super(this), initWithFrame: frame] };
+        let this: Retained<Self> = unsafe { msg_send_id![super(this), initWithFrame: frame] };
 
         this.setMultipleTouchEnabled(true);
 
@@ -372,13 +353,23 @@ impl WinitView {
         this
     }
 
+    fn window(&self) -> Option<Retained<WinitUIWindow>> {
+        // SAFETY: `WinitView`s are always installed in a `WinitUIWindow`
+        (**self).window().map(|window| unsafe { Retained::cast(window) })
+    }
+
     pub(crate) fn recognize_pinch_gesture(&self, should_recognize: bool) {
+        let mtm = MainThreadMarker::from(self);
         if should_recognize {
             if self.ivars().pinch_gesture_recognizer.borrow().is_none() {
-                let pinch: Id<UIPinchGestureRecognizer> = unsafe {
-                    msg_send_id![UIPinchGestureRecognizer::alloc(), initWithTarget: self, action: sel!(pinchGesture:)]
+                let pinch = unsafe {
+                    UIPinchGestureRecognizer::initWithTarget_action(
+                        mtm.alloc(),
+                        Some(self),
+                        Some(sel!(pinchGesture:)),
+                    )
                 };
-                pinch.setDelegate(ProtocolObject::from_ref(self));
+                pinch.setDelegate(Some(ProtocolObject::from_ref(self)));
                 self.addGestureRecognizer(&pinch);
                 self.ivars().pinch_gesture_recognizer.replace(Some(pinch));
             }
@@ -393,12 +384,17 @@ impl WinitView {
         minimum_number_of_touches: u8,
         maximum_number_of_touches: u8,
     ) {
+        let mtm = MainThreadMarker::from(self);
         if should_recognize {
             if self.ivars().pan_gesture_recognizer.borrow().is_none() {
-                let pan: Id<UIPanGestureRecognizer> = unsafe {
-                    msg_send_id![UIPanGestureRecognizer::alloc(), initWithTarget: self, action: sel!(panGesture:)]
+                let pan = unsafe {
+                    UIPanGestureRecognizer::initWithTarget_action(
+                        mtm.alloc(),
+                        Some(self),
+                        Some(sel!(panGesture:)),
+                    )
                 };
-                pan.setDelegate(ProtocolObject::from_ref(self));
+                pan.setDelegate(Some(ProtocolObject::from_ref(self)));
                 pan.setMinimumNumberOfTouches(minimum_number_of_touches as _);
                 pan.setMaximumNumberOfTouches(maximum_number_of_touches as _);
                 self.addGestureRecognizer(&pan);
@@ -410,12 +406,17 @@ impl WinitView {
     }
 
     pub(crate) fn recognize_doubletap_gesture(&self, should_recognize: bool) {
+        let mtm = MainThreadMarker::from(self);
         if should_recognize {
             if self.ivars().doubletap_gesture_recognizer.borrow().is_none() {
-                let tap: Id<UITapGestureRecognizer> = unsafe {
-                    msg_send_id![UITapGestureRecognizer::alloc(), initWithTarget: self, action: sel!(doubleTapGesture:)]
+                let tap = unsafe {
+                    UITapGestureRecognizer::initWithTarget_action(
+                        mtm.alloc(),
+                        Some(self),
+                        Some(sel!(doubleTapGesture:)),
+                    )
                 };
-                tap.setDelegate(ProtocolObject::from_ref(self));
+                tap.setDelegate(Some(ProtocolObject::from_ref(self)));
                 tap.setNumberOfTapsRequired(2);
                 tap.setNumberOfTouchesRequired(1);
                 self.addGestureRecognizer(&tap);
@@ -427,12 +428,17 @@ impl WinitView {
     }
 
     pub(crate) fn recognize_rotation_gesture(&self, should_recognize: bool) {
+        let mtm = MainThreadMarker::from(self);
         if should_recognize {
             if self.ivars().rotation_gesture_recognizer.borrow().is_none() {
-                let rotation: Id<UIRotationGestureRecognizer> = unsafe {
-                    msg_send_id![UIRotationGestureRecognizer::alloc(), initWithTarget: self, action: sel!(rotationGesture:)]
+                let rotation = unsafe {
+                    UIRotationGestureRecognizer::initWithTarget_action(
+                        mtm.alloc(),
+                        Some(self),
+                        Some(sel!(rotationGesture:)),
+                    )
                 };
-                rotation.setDelegate(ProtocolObject::from_ref(self));
+                rotation.setDelegate(Some(ProtocolObject::from_ref(self)));
                 self.addGestureRecognizer(&rotation);
                 self.ivars().rotation_gesture_recognizer.replace(Some(rotation));
             }
@@ -447,9 +453,9 @@ impl WinitView {
         let os_supports_force = app_state::os_capabilities().force_touch;
         for touch in touches {
             let logical_location = touch.locationInView(None);
-            let touch_type = touch.type_();
+            let touch_type = touch.r#type();
             let force = if os_supports_force {
-                let trait_collection = unsafe { self.traitCollection() };
+                let trait_collection = self.traitCollection();
                 let touch_capability = trait_collection.forceTouchCapability();
                 // Both the OS _and_ the device need to be checked for force touch support.
                 if touch_capability == UIForceTouchCapability::Available
@@ -474,7 +480,7 @@ impl WinitView {
             } else {
                 None
             };
-            let touch_id = touch as *const UITouch as u64;
+            let touch_id = touch as *const UITouch as usize;
             let phase = touch.phase();
             let phase = match phase {
                 UITouchPhase::Began => TouchPhase::Started,
@@ -482,7 +488,7 @@ impl WinitView {
                 // 2 is UITouchPhase::Stationary and is not expected here
                 UITouchPhase::Ended => TouchPhase::Ended,
                 UITouchPhase::Cancelled => TouchPhase::Cancelled,
-                _ => panic!("unexpected touch phase: {:?}", phase as i32),
+                _ => panic!("unexpected touch phase: {phase:?}"),
             };
 
             let physical_location = {
@@ -496,7 +502,7 @@ impl WinitView {
                 window_id: RootWindowId(window.id()),
                 event: WindowEvent::Touch(Touch {
                     device_id: DEVICE_ID,
-                    id: touch_id,
+                    finger_id: RootFingerId(FingerId(touch_id)),
                     location: physical_location,
                     force,
                     phase,

src/platform_impl/apple/uikit/view_controller.rs

@@ -1,14 +1,14 @@
 use std::cell::Cell;
 
-use objc2::rc::Id;
+use objc2::rc::Retained;
 use objc2::{declare_class, msg_send_id, mutability, ClassType, DeclaredClass};
 use objc2_foundation::{MainThreadMarker, NSObject};
-
-use super::app_state::{self};
-use super::uikit::{
+use objc2_ui_kit::{
     UIDevice, UIInterfaceOrientationMask, UIRectEdge, UIResponder, UIStatusBarStyle,
     UIUserInterfaceIdiom, UIView, UIViewController,
 };
+
+use super::app_state::{self};
 use crate::platform::ios::{ScreenEdge, StatusBarStyle, ValidOrientations};
 use crate::window::WindowAttributes;
 
@@ -26,7 +26,7 @@ declare_class!(
     unsafe impl ClassType for WinitViewController {
         #[inherits(UIResponder, NSObject)]
         type Super = UIViewController;
-        type Mutability = mutability::InteriorMutable;
+        type Mutability = mutability::MainThreadOnly;
         const NAME: &'static str = "WinitUIViewController";
     }
 
@@ -114,7 +114,7 @@ impl WinitViewController {
         mtm: MainThreadMarker,
         valid_orientations: ValidOrientations,
     ) {
-        let mask = match (valid_orientations, UIDevice::current(mtm).userInterfaceIdiom()) {
+        let mask = match (valid_orientations, UIDevice::currentDevice(mtm).userInterfaceIdiom()) {
             (ValidOrientations::LandscapeAndPortrait, UIUserInterfaceIdiom::Phone) => {
                 UIInterfaceOrientationMask::AllButUpsideDown
             },
@@ -129,23 +129,24 @@ impl WinitViewController {
             },
         };
         self.ivars().supported_orientations.set(mask);
-        UIViewController::attemptRotationToDeviceOrientation();
+        #[allow(deprecated)]
+        UIViewController::attemptRotationToDeviceOrientation(mtm);
     }
 
     pub(crate) fn new(
         mtm: MainThreadMarker,
         window_attributes: &WindowAttributes,
         view: &UIView,
-    ) -> Id<Self> {
+    ) -> Retained<Self> {
         // These are set properly below, we just to set them to something in the meantime.
-        let this = Self::alloc().set_ivars(ViewControllerState {
+        let this = mtm.alloc().set_ivars(ViewControllerState {
             prefers_status_bar_hidden: Cell::new(false),
             preferred_status_bar_style: Cell::new(UIStatusBarStyle::Default),
             prefers_home_indicator_auto_hidden: Cell::new(false),
             supported_orientations: Cell::new(UIInterfaceOrientationMask::All),
-            preferred_screen_edges_deferring_system_gestures: Cell::new(UIRectEdge::NONE),
+            preferred_screen_edges_deferring_system_gestures: Cell::new(UIRectEdge::empty()),
         });
-        let this: Id<Self> = unsafe { msg_send_id![super(this), init] };
+        let this: Retained<Self> = unsafe { msg_send_id![super(this), init] };
 
         this.set_prefers_status_bar_hidden(
             window_attributes.platform_specific.prefers_status_bar_hidden,

src/platform_impl/apple/uikit/window.rs

@@ -2,27 +2,28 @@
 
 use std::collections::VecDeque;
 
-use objc2::rc::Id;
+use objc2::rc::Retained;
 use objc2::runtime::{AnyObject, NSObject};
 use objc2::{class, declare_class, msg_send, msg_send_id, mutability, ClassType, DeclaredClass};
-use objc2_foundation::{CGFloat, CGPoint, CGRect, CGSize, MainThreadBound, MainThreadMarker};
+use objc2_foundation::{
+    CGFloat, CGPoint, CGRect, CGSize, MainThreadBound, MainThreadMarker, NSObjectProtocol,
+};
+use objc2_ui_kit::{
+    UIApplication, UICoordinateSpace, UIResponder, UIScreen, UIScreenOverscanCompensation,
+    UIViewController, UIWindow,
+};
 use tracing::{debug, warn};
 
 use super::app_state::EventWrapper;
-use super::uikit::{
-    UIApplication, UIResponder, UIScreen, UIScreenOverscanCompensation, UIViewController, UIWindow,
-};
 use super::view::WinitView;
 use super::view_controller::WinitViewController;
+use super::{app_state, monitor, ActiveEventLoop, Fullscreen, MonitorHandle};
 use crate::cursor::Cursor;
 use crate::dpi::{LogicalPosition, LogicalSize, PhysicalPosition, PhysicalSize, Position, Size};
 use crate::error::{ExternalError, NotSupportedError, OsError as RootOsError};
 use crate::event::{Event, WindowEvent};
 use crate::icon::Icon;
 use crate::platform::ios::{ScreenEdge, StatusBarStyle, ValidOrientations};
-use crate::platform_impl::platform::{
-    app_state, monitor, ActiveEventLoop, Fullscreen, MonitorHandle,
-};
 use crate::window::{
     CursorGrabMode, ImePurpose, ResizeDirection, Theme, UserAttentionType, WindowAttributes,
     WindowButtons, WindowId as RootWindowId, WindowLevel,
@@ -35,7 +36,7 @@ declare_class!(
     unsafe impl ClassType for WinitUIWindow {
         #[inherits(UIResponder, NSObject)]
         type Super = UIWindow;
-        type Mutability = mutability::InteriorMutable;
+        type Mutability = mutability::MainThreadOnly;
         const NAME: &'static str = "WinitUIWindow";
     }
 
@@ -76,8 +77,8 @@ impl WinitUIWindow {
         window_attributes: &WindowAttributes,
         frame: CGRect,
         view_controller: &UIViewController,
-    ) -> Id<Self> {
-        let this: Id<Self> = unsafe { msg_send_id![Self::alloc(), initWithFrame: frame] };
+    ) -> Retained<Self> {
+        let this: Retained<Self> = unsafe { msg_send_id![mtm.alloc(), initWithFrame: frame] };
 
         this.setRootViewController(Some(view_controller));
 
@@ -104,9 +105,9 @@ impl WinitUIWindow {
 }
 
 pub struct Inner {
-    window: Id<WinitUIWindow>,
-    view_controller: Id<WinitViewController>,
-    view: Id<WinitView>,
+    window: Retained<WinitUIWindow>,
+    view_controller: Retained<WinitViewController>,
+    view: Retained<WinitView>,
     gl_or_metal_backed: bool,
 }
 
@@ -394,44 +395,22 @@ impl Inner {
     }
 
     pub fn primary_monitor(&self) -> Option<MonitorHandle> {
-        Some(MonitorHandle::new(UIScreen::main(MainThreadMarker::new().unwrap())))
+        #[allow(deprecated)]
+        Some(MonitorHandle::new(UIScreen::mainScreen(MainThreadMarker::new().unwrap())))
     }
 
     pub fn id(&self) -> WindowId {
         self.window.id()
     }
 
-    #[cfg(feature = "rwh_04")]
-    pub fn raw_window_handle_rwh_04(&self) -> rwh_04::RawWindowHandle {
-        let mut window_handle = rwh_04::UiKitHandle::empty();
-        window_handle.ui_window = Id::as_ptr(&self.window) as _;
-        window_handle.ui_view = Id::as_ptr(&self.view) as _;
-        window_handle.ui_view_controller = Id::as_ptr(&self.view_controller) as _;
-        rwh_04::RawWindowHandle::UiKit(window_handle)
-    }
-
-    #[cfg(feature = "rwh_05")]
-    pub fn raw_window_handle_rwh_05(&self) -> rwh_05::RawWindowHandle {
-        let mut window_handle = rwh_05::UiKitWindowHandle::empty();
-        window_handle.ui_window = Id::as_ptr(&self.window) as _;
-        window_handle.ui_view = Id::as_ptr(&self.view) as _;
-        window_handle.ui_view_controller = Id::as_ptr(&self.view_controller) as _;
-        rwh_05::RawWindowHandle::UiKit(window_handle)
-    }
-
-    #[cfg(feature = "rwh_05")]
-    pub fn raw_display_handle_rwh_05(&self) -> rwh_05::RawDisplayHandle {
-        rwh_05::RawDisplayHandle::UiKit(rwh_05::UiKitDisplayHandle::empty())
-    }
-
     #[cfg(feature = "rwh_06")]
     pub fn raw_window_handle_rwh_06(&self) -> rwh_06::RawWindowHandle {
         let mut window_handle = rwh_06::UiKitWindowHandle::new({
-            let ui_view = Id::as_ptr(&self.view) as _;
-            std::ptr::NonNull::new(ui_view).expect("Id<T> should never be null")
+            let ui_view = Retained::as_ptr(&self.view) as _;
+            std::ptr::NonNull::new(ui_view).expect("Retained<T> should never be null")
         });
         window_handle.ui_view_controller =
-            std::ptr::NonNull::new(Id::as_ptr(&self.view_controller) as _);
+            std::ptr::NonNull::new(Retained::as_ptr(&self.view_controller) as _);
         rwh_06::RawWindowHandle::UiKit(window_handle)
     }
 
@@ -481,7 +460,8 @@ impl Window {
 
         // TODO: transparency, visible
 
-        let main_screen = UIScreen::main(mtm);
+        #[allow(deprecated)]
+        let main_screen = UIScreen::mainScreen(mtm);
         let fullscreen = window_attributes.fullscreen.clone().map(Into::into);
         let screen = match fullscreen {
             Some(Fullscreen::Exclusive(ref video_mode)) => video_mode.monitor.ui_screen(mtm),
@@ -505,12 +485,8 @@ impl Window {
 
         let view = WinitView::new(mtm, &window_attributes, frame);
 
-        let gl_or_metal_backed = unsafe {
-            let layer_class = WinitView::layerClass();
-            let is_metal = msg_send![layer_class, isSubclassOfClass: class!(CAMetalLayer)];
-            let is_gl = msg_send![layer_class, isSubclassOfClass: class!(CAEAGLLayer)];
-            is_metal || is_gl
-        };
+        let gl_or_metal_backed =
+            view.isKindOfClass(class!(CAMetalLayer)) || view.isKindOfClass(class!(CAEAGLLayer));
 
         let view_controller = WinitViewController::new(mtm, &window_attributes, &view);
         let window = WinitUIWindow::new(mtm, &window_attributes, frame, &view_controller);
@@ -674,10 +650,8 @@ impl Inner {
         } else {
             let screen_frame = self.rect_to_screen_space(bounds);
             let status_bar_frame = {
-                let app = UIApplication::shared(MainThreadMarker::new().unwrap()).expect(
-                    "`Window::get_inner_position` cannot be called before `EventLoop::run_app` on \
-                     iOS",
-                );
+                let app = UIApplication::sharedApplication(MainThreadMarker::new().unwrap());
+                #[allow(deprecated)]
                 app.statusBarFrame()
             };
             let (y, height) = if screen_frame.origin.y > status_bar_frame.size.height {
@@ -702,7 +676,7 @@ pub struct WindowId {
 }
 
 impl WindowId {
-    pub const unsafe fn dummy() -> Self {
+    pub const fn dummy() -> Self {
         WindowId { window: std::ptr::null_mut() }
     }
 }
@@ -728,7 +702,7 @@ impl From<&AnyObject> for WindowId {
     }
 }
 
-#[derive(Clone, Debug, Default)]
+#[derive(Clone, Debug, Default, PartialEq)]
 pub struct PlatformSpecificWindowAttributes {
     pub scale_factor: Option<f64>,
     pub valid_orientations: ValidOrientations,

src/platform_impl/ios/app_delegate.rs

@@ -1,101 +0,0 @@
-use objc2::{declare_class, mutability, ClassType, DeclaredClass};
-use objc2_foundation::{MainThreadMarker, NSObject, NSObjectProtocol};
-
-use super::app_state::{self, EventWrapper};
-use super::uikit::{UIApplication, UIWindow};
-use super::window::WinitUIWindow;
-use crate::event::{Event, WindowEvent};
-use crate::window::WindowId as RootWindowId;
-
-declare_class!(
-    pub struct AppDelegate;
-
-    unsafe impl ClassType for AppDelegate {
-        type Super = NSObject;
-        type Mutability = mutability::InteriorMutable;
-        const NAME: &'static str = "WinitApplicationDelegate";
-    }
-
-    impl DeclaredClass for AppDelegate {}
-
-    // UIApplicationDelegate protocol
-    unsafe impl AppDelegate {
-        #[method(application:didFinishLaunchingWithOptions:)]
-        fn did_finish_launching(&self, _application: &UIApplication, _: *mut NSObject) -> bool {
-            app_state::did_finish_launching(MainThreadMarker::new().unwrap());
-            true
-        }
-
-        #[method(applicationDidBecomeActive:)]
-        fn did_become_active(&self, _application: &UIApplication) {
-            let mtm = MainThreadMarker::new().unwrap();
-            app_state::handle_nonuser_event(mtm, EventWrapper::StaticEvent(Event::Resumed))
-        }
-
-        #[method(applicationWillResignActive:)]
-        fn will_resign_active(&self, _application: &UIApplication) {
-            let mtm = MainThreadMarker::new().unwrap();
-            app_state::handle_nonuser_event(mtm, EventWrapper::StaticEvent(Event::Suspended))
-        }
-
-        #[method(applicationWillEnterForeground:)]
-        fn will_enter_foreground(&self, application: &UIApplication) {
-            self.send_occluded_event_for_all_windows(application, false);
-        }
-
-        #[method(applicationDidEnterBackground:)]
-        fn did_enter_background(&self, application: &UIApplication) {
-            self.send_occluded_event_for_all_windows(application, true);
-        }
-
-        #[method(applicationWillTerminate:)]
-        fn will_terminate(&self, application: &UIApplication) {
-            let mut events = Vec::new();
-            for window in application.windows().iter() {
-                if window.is_kind_of::<WinitUIWindow>() {
-                    // SAFETY: We just checked that the window is a `winit` window
-                    let window = unsafe {
-                        let ptr: *const UIWindow = window;
-                        let ptr: *const WinitUIWindow = ptr.cast();
-                        &*ptr
-                    };
-                    events.push(EventWrapper::StaticEvent(Event::WindowEvent {
-                        window_id: RootWindowId(window.id()),
-                        event: WindowEvent::Destroyed,
-                    }));
-                }
-            }
-            let mtm = MainThreadMarker::new().unwrap();
-            app_state::handle_nonuser_events(mtm, events);
-            app_state::terminated(mtm);
-        }
-
-        #[method(applicationDidReceiveMemoryWarning:)]
-        fn did_receive_memory_warning(&self, _application: &UIApplication) {
-            let mtm = MainThreadMarker::new().unwrap();
-            app_state::handle_nonuser_event(mtm, EventWrapper::StaticEvent(Event::MemoryWarning))
-        }
-    }
-);
-
-impl AppDelegate {
-    fn send_occluded_event_for_all_windows(&self, application: &UIApplication, occluded: bool) {
-        let mut events = Vec::new();
-        for window in application.windows().iter() {
-            if window.is_kind_of::<WinitUIWindow>() {
-                // SAFETY: We just checked that the window is a `winit` window
-                let window = unsafe {
-                    let ptr: *const UIWindow = window;
-                    let ptr: *const WinitUIWindow = ptr.cast();
-                    &*ptr
-                };
-                events.push(EventWrapper::StaticEvent(Event::WindowEvent {
-                    window_id: RootWindowId(window.id()),
-                    event: WindowEvent::Occluded(occluded),
-                }));
-            }
-        }
-        let mtm = MainThreadMarker::new().unwrap();
-        app_state::handle_nonuser_events(mtm, events);
-    }
-}

src/platform_impl/ios/uikit/application.rs

@@ -1,31 +0,0 @@
-use objc2::rc::Id;
-use objc2::{extern_class, extern_methods, msg_send_id, mutability, ClassType};
-use objc2_foundation::{CGRect, MainThreadMarker, NSArray, NSObject};
-
-use super::{UIResponder, UIWindow};
-
-extern_class!(
-    #[derive(Debug, PartialEq, Eq, Hash)]
-    pub(crate) struct UIApplication;
-
-    unsafe impl ClassType for UIApplication {
-        #[inherits(NSObject)]
-        type Super = UIResponder;
-        type Mutability = mutability::InteriorMutable;
-    }
-);
-
-extern_methods!(
-    unsafe impl UIApplication {
-        pub fn shared(_mtm: MainThreadMarker) -> Option<Id<Self>> {
-            unsafe { msg_send_id![Self::class(), sharedApplication] }
-        }
-
-        pub fn windows(&self) -> Id<NSArray<UIWindow>> {
-            unsafe { msg_send_id![self, windows] }
-        }
-
-        #[method(statusBarFrame)]
-        pub fn statusBarFrame(&self) -> CGRect;
-    }
-);

src/platform_impl/ios/uikit/coordinate_space.rs

@@ -1,12 +0,0 @@
-use objc2::{extern_class, mutability, ClassType};
-use objc2_foundation::NSObject;
-
-extern_class!(
-    #[derive(Debug, PartialEq, Eq, Hash)]
-    pub(crate) struct UICoordinateSpace;
-
-    unsafe impl ClassType for UICoordinateSpace {
-        type Super = NSObject;
-        type Mutability = mutability::InteriorMutable;
-    }
-);

src/platform_impl/ios/uikit/device.rs

@@ -1,41 +0,0 @@
-use objc2::encode::{Encode, Encoding};
-use objc2::rc::Id;
-use objc2::{extern_class, extern_methods, msg_send_id, mutability, ClassType};
-use objc2_foundation::{MainThreadMarker, NSInteger, NSObject};
-
-extern_class!(
-    #[derive(Debug, PartialEq, Eq, Hash)]
-    pub(crate) struct UIDevice;
-
-    unsafe impl ClassType for UIDevice {
-        type Super = NSObject;
-        type Mutability = mutability::InteriorMutable;
-    }
-);
-
-extern_methods!(
-    unsafe impl UIDevice {
-        pub fn current(_mtm: MainThreadMarker) -> Id<Self> {
-            unsafe { msg_send_id![Self::class(), currentDevice] }
-        }
-
-        #[method(userInterfaceIdiom)]
-        pub fn userInterfaceIdiom(&self) -> UIUserInterfaceIdiom;
-    }
-);
-
-#[repr(transparent)]
-#[derive(Clone, Copy, Debug, PartialEq, Eq)]
-pub struct UIUserInterfaceIdiom(NSInteger);
-
-unsafe impl Encode for UIUserInterfaceIdiom {
-    const ENCODING: Encoding = NSInteger::ENCODING;
-}
-
-impl UIUserInterfaceIdiom {
-    pub const Unspecified: UIUserInterfaceIdiom = UIUserInterfaceIdiom(-1);
-    pub const Phone: UIUserInterfaceIdiom = UIUserInterfaceIdiom(0);
-    pub const Pad: UIUserInterfaceIdiom = UIUserInterfaceIdiom(1);
-    pub const TV: UIUserInterfaceIdiom = UIUserInterfaceIdiom(2);
-    pub const CarPlay: UIUserInterfaceIdiom = UIUserInterfaceIdiom(3);
-}

src/platform_impl/ios/uikit/event.rs

@@ -1,12 +0,0 @@
-use objc2::{extern_class, mutability, ClassType};
-use objc2_foundation::NSObject;
-
-extern_class!(
-    #[derive(Debug, PartialEq, Eq, Hash)]
-    pub(crate) struct UIEvent;
-
-    unsafe impl ClassType for UIEvent {
-        type Super = NSObject;
-        type Mutability = mutability::InteriorMutable;
-    }
-);

src/platform_impl/ios/uikit/geometry.rs

@@ -1,14 +0,0 @@
-use objc2::encode::{Encode, Encoding};
-use objc2_foundation::NSUInteger;
-
-#[repr(transparent)]
-#[derive(Clone, Copy, Debug, PartialEq, Eq)]
-pub struct UIRectEdge(pub NSUInteger);
-
-impl UIRectEdge {
-    pub const NONE: Self = Self(0);
-}
-
-unsafe impl Encode for UIRectEdge {
-    const ENCODING: Encoding = NSUInteger::ENCODING;
-}

src/platform_impl/ios/uikit/gesture_recognizer.rs

@@ -1,176 +0,0 @@
-use objc2::encode::{Encode, Encoding};
-use objc2::rc::Id;
-use objc2::runtime::ProtocolObject;
-use objc2::{extern_class, extern_methods, extern_protocol, mutability, ClassType, ProtocolType};
-use objc2_foundation::{CGFloat, CGPoint, NSInteger, NSObject, NSObjectProtocol, NSUInteger};
-
-use super::UIView;
-
-extern_class!(
-    /// [`UIGestureRecognizer`](https://developer.apple.com/documentation/uikit/uigesturerecognizer)
-    #[derive(Debug, PartialEq, Eq, Hash)]
-    pub(crate) struct UIGestureRecognizer;
-
-    unsafe impl ClassType for UIGestureRecognizer {
-        type Super = NSObject;
-        type Mutability = mutability::InteriorMutable;
-    }
-);
-
-extern_methods!(
-    unsafe impl UIGestureRecognizer {
-        #[method(state)]
-        pub fn state(&self) -> UIGestureRecognizerState;
-
-        /// [`delegate`](https://developer.apple.com/documentation/uikit/uigesturerecognizer/1624207-delegate?language=objc)
-        /// @property(nullable, nonatomic, weak) id<UIGestureRecognizerDelegate> delegate;
-        #[method(setDelegate:)]
-        pub fn setDelegate(&self, delegate: &ProtocolObject<dyn UIGestureRecognizerDelegate>);
-
-        #[method_id(delegate)]
-        pub fn delegate(&self) -> Id<ProtocolObject<dyn UIGestureRecognizerDelegate>>;
-    }
-);
-
-unsafe impl Encode for UIGestureRecognizer {
-    const ENCODING: Encoding = Encoding::Object;
-}
-
-// [`UIGestureRecognizerState`](https://developer.apple.com/documentation/uikit/uigesturerecognizer/state)
-#[repr(transparent)]
-#[derive(Clone, Copy, Debug, PartialEq, Eq)]
-pub struct UIGestureRecognizerState(NSInteger);
-
-unsafe impl Encode for UIGestureRecognizerState {
-    const ENCODING: Encoding = NSInteger::ENCODING;
-}
-
-#[allow(dead_code)]
-impl UIGestureRecognizerState {
-    pub const Possible: Self = Self(0);
-    pub const Began: Self = Self(1);
-    pub const Changed: Self = Self(2);
-    pub const Ended: Self = Self(3);
-    pub const Cancelled: Self = Self(4);
-    pub const Failed: Self = Self(5);
-}
-
-// [`UIPinchGestureRecognizer`](https://developer.apple.com/documentation/uikit/uipinchgesturerecognizer)
-extern_class!(
-    #[derive(Debug, PartialEq, Eq, Hash)]
-    pub(crate) struct UIPinchGestureRecognizer;
-
-    unsafe impl ClassType for UIPinchGestureRecognizer {
-        type Super = UIGestureRecognizer;
-        type Mutability = mutability::InteriorMutable;
-    }
-);
-
-extern_methods!(
-    unsafe impl UIPinchGestureRecognizer {
-        #[method(scale)]
-        pub fn scale(&self) -> CGFloat;
-
-        #[method(velocity)]
-        pub fn velocity(&self) -> CGFloat;
-    }
-);
-
-unsafe impl Encode for UIPinchGestureRecognizer {
-    const ENCODING: Encoding = Encoding::Object;
-}
-
-extern_class!(
-    /// [`UIRotationGestureRecognizer`](https://developer.apple.com/documentation/uikit/uirotationgesturerecognizer)
-    #[derive(Debug, PartialEq, Eq, Hash)]
-    pub(crate) struct UIRotationGestureRecognizer;
-
-    unsafe impl ClassType for UIRotationGestureRecognizer {
-        type Super = UIGestureRecognizer;
-        type Mutability = mutability::InteriorMutable;
-    }
-);
-
-extern_methods!(
-    unsafe impl UIRotationGestureRecognizer {
-        #[method(rotation)]
-        pub fn rotation(&self) -> CGFloat;
-
-        #[method(velocity)]
-        pub fn velocity(&self) -> CGFloat;
-    }
-);
-
-unsafe impl Encode for UIRotationGestureRecognizer {
-    const ENCODING: Encoding = Encoding::Object;
-}
-
-extern_class!(
-    /// [`UITapGestureRecognizer`](https://developer.apple.com/documentation/uikit/uitapgesturerecognizer)
-    #[derive(Debug, PartialEq, Eq, Hash)]
-    pub(crate) struct UITapGestureRecognizer;
-
-    unsafe impl ClassType for UITapGestureRecognizer {
-        type Super = UIGestureRecognizer;
-        type Mutability = mutability::InteriorMutable;
-    }
-);
-
-extern_methods!(
-    unsafe impl UITapGestureRecognizer {
-        #[method(setNumberOfTapsRequired:)]
-        pub fn setNumberOfTapsRequired(&self, number_of_taps_required: NSUInteger);
-
-        #[method(setNumberOfTouchesRequired:)]
-        pub fn setNumberOfTouchesRequired(&self, number_of_touches_required: NSUInteger);
-    }
-);
-
-unsafe impl Encode for UITapGestureRecognizer {
-    const ENCODING: Encoding = Encoding::Object;
-}
-
-extern_class!(
-    /// [`UIPanGestureRecognizer`](https://developer.apple.com/documentation/uikit/uipangesturerecognizer)
-    #[derive(Debug, PartialEq, Eq, Hash)]
-    pub(crate) struct UIPanGestureRecognizer;
-
-    unsafe impl ClassType for UIPanGestureRecognizer {
-        type Super = UIGestureRecognizer;
-        type Mutability = mutability::InteriorMutable;
-    }
-);
-
-extern_methods!(
-    unsafe impl UIPanGestureRecognizer {
-        #[method(translationInView:)]
-        pub fn translationInView(&self, view: &UIView) -> CGPoint;
-
-        #[method(setTranslation:inView:)]
-        pub fn setTranslationInView(&self, translation: CGPoint, view: &UIView);
-
-        #[method(velocityInView:)]
-        pub fn velocityInView(&self, view: &UIView) -> CGPoint;
-
-        #[method(setMinimumNumberOfTouches:)]
-        pub fn setMinimumNumberOfTouches(&self, minimum_number_of_touches: NSUInteger);
-
-        #[method(minimumNumberOfTouches)]
-        pub fn minimumNumberOfTouches(&self) -> NSUInteger;
-
-        #[method(setMaximumNumberOfTouches:)]
-        pub fn setMaximumNumberOfTouches(&self, maximum_number_of_touches: NSUInteger);
-
-        #[method(maximumNumberOfTouches)]
-        pub fn maximumNumberOfTouches(&self) -> NSUInteger;
-    }
-);
-
-extern_protocol!(
-    /// (@protocol UIGestureRecognizerDelegate)[https://developer.apple.com/documentation/uikit/uigesturerecognizerdelegate?language=objc]
-    pub(crate) unsafe trait UIGestureRecognizerDelegate: NSObjectProtocol {}
-
-    unsafe impl ProtocolType for dyn UIGestureRecognizerDelegate {
-        const NAME: &'static str = "UIGestureRecognizerDelegate";
-    }
-);

src/platform_impl/ios/uikit/mod.rs

@@ -1,53 +0,0 @@
-#![allow(non_snake_case)]
-#![allow(non_upper_case_globals)]
-
-use std::os::raw::{c_char, c_int};
-
-use objc2_foundation::NSString;
-
-mod application;
-mod coordinate_space;
-mod device;
-mod event;
-mod geometry;
-mod gesture_recognizer;
-mod responder;
-mod screen;
-mod screen_mode;
-mod status_bar_style;
-mod touch;
-mod trait_collection;
-mod view;
-mod view_controller;
-mod window;
-
-pub(crate) use self::application::UIApplication;
-pub(crate) use self::coordinate_space::UICoordinateSpace;
-pub(crate) use self::device::{UIDevice, UIUserInterfaceIdiom};
-pub(crate) use self::event::UIEvent;
-pub(crate) use self::geometry::UIRectEdge;
-pub(crate) use self::gesture_recognizer::{
-    UIGestureRecognizer, UIGestureRecognizerDelegate, UIGestureRecognizerState,
-    UIPanGestureRecognizer, UIPinchGestureRecognizer, UIRotationGestureRecognizer,
-    UITapGestureRecognizer,
-};
-pub(crate) use self::responder::UIResponder;
-pub(crate) use self::screen::{UIScreen, UIScreenOverscanCompensation};
-pub(crate) use self::screen_mode::UIScreenMode;
-pub(crate) use self::status_bar_style::UIStatusBarStyle;
-pub(crate) use self::touch::{UITouch, UITouchPhase, UITouchType};
-pub(crate) use self::trait_collection::{UIForceTouchCapability, UITraitCollection};
-#[allow(unused_imports)]
-pub(crate) use self::view::{UIEdgeInsets, UIView};
-pub(crate) use self::view_controller::{UIInterfaceOrientationMask, UIViewController};
-pub(crate) use self::window::UIWindow;
-
-#[link(name = "UIKit", kind = "framework")]
-extern "C" {
-    pub fn UIApplicationMain(
-        argc: c_int,
-        argv: *const c_char,
-        principalClassName: Option<&NSString>,
-        delegateClassName: Option<&NSString>,
-    ) -> c_int;
-}

src/platform_impl/ios/uikit/responder.rs

@@ -1,12 +0,0 @@
-use objc2::{extern_class, mutability, ClassType};
-use objc2_foundation::NSObject;
-
-extern_class!(
-    #[derive(Debug, PartialEq, Eq, Hash)]
-    pub(crate) struct UIResponder;
-
-    unsafe impl ClassType for UIResponder {
-        type Super = NSObject;
-        type Mutability = mutability::InteriorMutable;
-    }
-);

src/platform_impl/ios/uikit/screen.rs

@@ -1,80 +0,0 @@
-use objc2::encode::{Encode, Encoding};
-use objc2::rc::Id;
-use objc2::{extern_class, extern_methods, msg_send_id, mutability, ClassType};
-use objc2_foundation::{CGFloat, CGRect, MainThreadMarker, NSArray, NSInteger, NSObject};
-
-use super::{UICoordinateSpace, UIScreenMode};
-
-extern_class!(
-    #[derive(Debug, PartialEq, Eq, Hash)]
-    pub(crate) struct UIScreen;
-
-    unsafe impl ClassType for UIScreen {
-        type Super = NSObject;
-        type Mutability = mutability::InteriorMutable;
-    }
-);
-
-extern_methods!(
-    unsafe impl UIScreen {
-        pub fn main(_mtm: MainThreadMarker) -> Id<Self> {
-            unsafe { msg_send_id![Self::class(), mainScreen] }
-        }
-
-        pub fn screens(_mtm: MainThreadMarker) -> Id<NSArray<Self>> {
-            unsafe { msg_send_id![Self::class(), screens] }
-        }
-
-        #[method(bounds)]
-        pub fn bounds(&self) -> CGRect;
-
-        #[method(scale)]
-        pub fn scale(&self) -> CGFloat;
-
-        #[method(nativeBounds)]
-        pub fn nativeBounds(&self) -> CGRect;
-
-        #[method(nativeScale)]
-        pub fn nativeScale(&self) -> CGFloat;
-
-        #[method(maximumFramesPerSecond)]
-        pub fn maximumFramesPerSecond(&self) -> NSInteger;
-
-        pub fn mirroredScreen(&self) -> Id<Self> {
-            unsafe { msg_send_id![Self::class(), mirroredScreen] }
-        }
-
-        pub fn preferredMode(&self) -> Option<Id<UIScreenMode>> {
-            unsafe { msg_send_id![self, preferredMode] }
-        }
-
-        #[method(setCurrentMode:)]
-        pub fn setCurrentMode(&self, mode: Option<&UIScreenMode>);
-
-        pub fn availableModes(&self) -> Id<NSArray<UIScreenMode>> {
-            unsafe { msg_send_id![self, availableModes] }
-        }
-
-        #[method(setOverscanCompensation:)]
-        pub fn setOverscanCompensation(&self, overscanCompensation: UIScreenOverscanCompensation);
-
-        pub fn coordinateSpace(&self) -> Id<UICoordinateSpace> {
-            unsafe { msg_send_id![self, coordinateSpace] }
-        }
-    }
-);
-
-#[repr(transparent)]
-#[derive(Clone, Copy, Debug, PartialEq, Eq)]
-pub struct UIScreenOverscanCompensation(NSInteger);
-
-unsafe impl Encode for UIScreenOverscanCompensation {
-    const ENCODING: Encoding = NSInteger::ENCODING;
-}
-
-#[allow(dead_code)]
-impl UIScreenOverscanCompensation {
-    pub const Scale: Self = Self(0);
-    pub const InsetBounds: Self = Self(1);
-    pub const None: Self = Self(2);
-}

src/platform_impl/ios/uikit/screen_mode.rs

@@ -1,19 +0,0 @@
-use objc2::{extern_class, extern_methods, mutability, ClassType};
-use objc2_foundation::{CGSize, NSObject};
-
-extern_class!(
-    #[derive(Debug, PartialEq, Eq, Hash)]
-    pub(crate) struct UIScreenMode;
-
-    unsafe impl ClassType for UIScreenMode {
-        type Super = NSObject;
-        type Mutability = mutability::InteriorMutable;
-    }
-);
-
-extern_methods!(
-    unsafe impl UIScreenMode {
-        #[method(size)]
-        pub fn size(&self) -> CGSize;
-    }
-);

src/platform_impl/ios/uikit/status_bar_style.rs

@@ -1,16 +0,0 @@
-use objc2::encode::{Encode, Encoding};
-use objc2_foundation::NSInteger;
-
-#[derive(Clone, Copy, Debug, Default, PartialEq, Eq)]
-#[allow(dead_code)]
-#[repr(isize)]
-pub enum UIStatusBarStyle {
-    #[default]
-    Default = 0,
-    LightContent = 1,
-    DarkContent = 3,
-}
-
-unsafe impl Encode for UIStatusBarStyle {
-    const ENCODING: Encoding = NSInteger::ENCODING;
-}

src/platform_impl/ios/uikit/touch.rs

@@ -1,65 +0,0 @@
-use objc2::encode::{Encode, Encoding};
-use objc2::{extern_class, extern_methods, mutability, ClassType};
-use objc2_foundation::{CGFloat, CGPoint, NSInteger, NSObject};
-
-use super::UIView;
-
-extern_class!(
-    #[derive(Debug, PartialEq, Eq, Hash)]
-    pub(crate) struct UITouch;
-
-    unsafe impl ClassType for UITouch {
-        type Super = NSObject;
-        type Mutability = mutability::InteriorMutable;
-    }
-);
-
-extern_methods!(
-    unsafe impl UITouch {
-        #[method(locationInView:)]
-        pub fn locationInView(&self, view: Option<&UIView>) -> CGPoint;
-
-        #[method(type)]
-        pub fn type_(&self) -> UITouchType;
-
-        #[method(force)]
-        pub fn force(&self) -> CGFloat;
-
-        #[method(maximumPossibleForce)]
-        pub fn maximumPossibleForce(&self) -> CGFloat;
-
-        #[method(altitudeAngle)]
-        pub fn altitudeAngle(&self) -> CGFloat;
-
-        #[method(phase)]
-        pub fn phase(&self) -> UITouchPhase;
-    }
-);
-
-#[derive(Debug, PartialEq, Eq)]
-#[allow(dead_code)]
-#[repr(isize)]
-pub enum UITouchType {
-    Direct = 0,
-    Indirect,
-    Pencil,
-}
-
-unsafe impl Encode for UITouchType {
-    const ENCODING: Encoding = NSInteger::ENCODING;
-}
-
-#[derive(Debug)]
-#[allow(dead_code)]
-#[repr(isize)]
-pub enum UITouchPhase {
-    Began = 0,
-    Moved,
-    Stationary,
-    Ended,
-    Cancelled,
-}
-
-unsafe impl Encode for UITouchPhase {
-    const ENCODING: Encoding = NSInteger::ENCODING;
-}

src/platform_impl/ios/uikit/trait_collection.rs

@@ -1,33 +0,0 @@
-use objc2::encode::{Encode, Encoding};
-use objc2::{extern_class, extern_methods, mutability, ClassType};
-use objc2_foundation::{NSInteger, NSObject};
-
-extern_class!(
-    #[derive(Debug, PartialEq, Eq, Hash)]
-    pub(crate) struct UITraitCollection;
-
-    unsafe impl ClassType for UITraitCollection {
-        type Super = NSObject;
-        type Mutability = mutability::InteriorMutable;
-    }
-);
-
-extern_methods!(
-    unsafe impl UITraitCollection {
-        #[method(forceTouchCapability)]
-        pub fn forceTouchCapability(&self) -> UIForceTouchCapability;
-    }
-);
-
-#[derive(Debug, PartialEq, Eq)]
-#[allow(dead_code)]
-#[repr(isize)]
-pub enum UIForceTouchCapability {
-    Unknown = 0,
-    Unavailable,
-    Available,
-}
-
-unsafe impl Encode for UIForceTouchCapability {
-    const ENCODING: Encoding = NSInteger::ENCODING;
-}

src/platform_impl/ios/uikit/view.rs

@@ -1,93 +0,0 @@
-use objc2::encode::{Encode, Encoding};
-use objc2::rc::Id;
-use objc2::{extern_class, extern_methods, msg_send_id, mutability, ClassType};
-use objc2_foundation::{CGFloat, CGRect, NSObject};
-
-use super::{UICoordinateSpace, UIGestureRecognizer, UIResponder, UIViewController};
-
-extern_class!(
-    #[derive(Debug, PartialEq, Eq, Hash)]
-    pub(crate) struct UIView;
-
-    unsafe impl ClassType for UIView {
-        #[inherits(NSObject)]
-        type Super = UIResponder;
-        type Mutability = mutability::InteriorMutable;
-    }
-);
-
-extern_methods!(
-    unsafe impl UIView {
-        #[method(bounds)]
-        pub fn bounds(&self) -> CGRect;
-
-        #[method(setBounds:)]
-        pub fn setBounds(&self, value: CGRect);
-
-        #[method(frame)]
-        pub fn frame(&self) -> CGRect;
-
-        #[method(setFrame:)]
-        pub fn setFrame(&self, value: CGRect);
-
-        #[method(contentScaleFactor)]
-        pub fn contentScaleFactor(&self) -> CGFloat;
-
-        #[method(setContentScaleFactor:)]
-        pub fn setContentScaleFactor(&self, val: CGFloat);
-
-        #[method(setMultipleTouchEnabled:)]
-        pub fn setMultipleTouchEnabled(&self, val: bool);
-
-        pub fn rootViewController(&self) -> Option<Id<UIViewController>> {
-            unsafe { msg_send_id![self, rootViewController] }
-        }
-
-        #[method(setRootViewController:)]
-        pub fn setRootViewController(&self, rootViewController: Option<&UIViewController>);
-
-        #[method(convertRect:toCoordinateSpace:)]
-        pub fn convertRect_toCoordinateSpace(
-            &self,
-            rect: CGRect,
-            coordinateSpace: &UICoordinateSpace,
-        ) -> CGRect;
-
-        #[method(convertRect:fromCoordinateSpace:)]
-        pub fn convertRect_fromCoordinateSpace(
-            &self,
-            rect: CGRect,
-            coordinateSpace: &UICoordinateSpace,
-        ) -> CGRect;
-
-        #[method(safeAreaInsets)]
-        pub fn safeAreaInsets(&self) -> UIEdgeInsets;
-
-        #[method(setNeedsDisplay)]
-        pub fn setNeedsDisplay(&self);
-
-        #[method(addGestureRecognizer:)]
-        pub fn addGestureRecognizer(&self, gestureRecognizer: &UIGestureRecognizer);
-
-        #[method(removeGestureRecognizer:)]
-        pub fn removeGestureRecognizer(&self, gestureRecognizer: &UIGestureRecognizer);
-    }
-);
-
-#[repr(C)]
-#[derive(Debug, Clone)]
-pub struct UIEdgeInsets {
-    pub top: CGFloat,
-    pub left: CGFloat,
-    pub bottom: CGFloat,
-    pub right: CGFloat,
-}
-
-unsafe impl Encode for UIEdgeInsets {
-    const ENCODING: Encoding = Encoding::Struct("UIEdgeInsets", &[
-        CGFloat::ENCODING,
-        CGFloat::ENCODING,
-        CGFloat::ENCODING,
-        CGFloat::ENCODING,
-    ]);
-}

src/platform_impl/ios/uikit/view_controller.rs

@@ -1,57 +0,0 @@
-use objc2::encode::{Encode, Encoding};
-use objc2::rc::Id;
-use objc2::{extern_class, extern_methods, msg_send_id, mutability, ClassType};
-use objc2_foundation::{NSObject, NSUInteger};
-
-use super::{UIResponder, UIView};
-
-extern_class!(
-    #[derive(Debug, PartialEq, Eq, Hash)]
-    pub(crate) struct UIViewController;
-
-    unsafe impl ClassType for UIViewController {
-        #[inherits(NSObject)]
-        type Super = UIResponder;
-        type Mutability = mutability::InteriorMutable;
-    }
-);
-
-extern_methods!(
-    unsafe impl UIViewController {
-        #[method(attemptRotationToDeviceOrientation)]
-        pub fn attemptRotationToDeviceOrientation();
-
-        #[method(setNeedsStatusBarAppearanceUpdate)]
-        pub fn setNeedsStatusBarAppearanceUpdate(&self);
-
-        #[method(setNeedsUpdateOfHomeIndicatorAutoHidden)]
-        pub fn setNeedsUpdateOfHomeIndicatorAutoHidden(&self);
-
-        #[method(setNeedsUpdateOfScreenEdgesDeferringSystemGestures)]
-        pub fn setNeedsUpdateOfScreenEdgesDeferringSystemGestures(&self);
-
-        pub fn view(&self) -> Option<Id<UIView>> {
-            unsafe { msg_send_id![self, view] }
-        }
-
-        #[method(setView:)]
-        pub fn setView(&self, view: Option<&UIView>);
-    }
-);
-
-bitflags::bitflags! {
-    #[derive(Clone, Copy)]
-    pub struct UIInterfaceOrientationMask: NSUInteger {
-        const Portrait = 1 << 1;
-        const PortraitUpsideDown = 1 << 2;
-        const LandscapeRight = 1 << 3;
-        const LandscapeLeft = 1 << 4;
-        const Landscape = Self::LandscapeLeft.bits() | Self::LandscapeRight.bits();
-        const AllButUpsideDown = Self::Landscape.bits() | Self::Portrait.bits();
-        const All = Self::AllButUpsideDown.bits() | Self::PortraitUpsideDown.bits();
-    }
-}
-
-unsafe impl Encode for UIInterfaceOrientationMask {
-    const ENCODING: Encoding = NSUInteger::ENCODING;
-}

src/platform_impl/ios/uikit/window.rs

@@ -1,36 +0,0 @@
-use objc2::rc::Id;
-use objc2::{extern_class, extern_methods, msg_send_id, mutability, ClassType};
-use objc2_foundation::NSObject;
-
-use super::{UIResponder, UIScreen, UIView};
-
-extern_class!(
-    #[derive(Debug, PartialEq, Eq, Hash)]
-    pub(crate) struct UIWindow;
-
-    unsafe impl ClassType for UIWindow {
-        #[inherits(UIResponder, NSObject)]
-        type Super = UIView;
-        type Mutability = mutability::InteriorMutable;
-    }
-);
-
-extern_methods!(
-    unsafe impl UIWindow {
-        pub fn screen(&self) -> Id<UIScreen> {
-            unsafe { msg_send_id![self, screen] }
-        }
-
-        #[method(setScreen:)]
-        pub fn setScreen(&self, screen: &UIScreen);
-
-        #[method(setHidden:)]
-        pub fn setHidden(&self, flag: bool);
-
-        #[method(makeKeyAndVisible)]
-        pub fn makeKeyAndVisible(&self);
-
-        #[method(isKeyWindow)]
-        pub fn isKeyWindow(&self) -> bool;
-    }
-);

src/platform_impl/linux/common/xkb/compose.rs

@@ -6,13 +6,14 @@ use std::ops::Deref;
 use std::os::unix::ffi::OsStringExt;
 use std::ptr::NonNull;
 
-use super::{XkbContext, XKBCH};
 use smol_str::SmolStr;
 use xkbcommon_dl::{
     xkb_compose_compile_flags, xkb_compose_feed_result, xkb_compose_state, xkb_compose_state_flags,
     xkb_compose_status, xkb_compose_table, xkb_keysym_t,
 };
 
+use super::{XkbContext, XKBCH};
+
 #[derive(Debug)]
 pub struct XkbComposeTable {
     table: NonNull<xkb_compose_table>,

src/platform_impl/linux/common/xkb/keymap.rs

@@ -6,14 +6,13 @@ use std::ptr::{self, NonNull};
 
 #[cfg(x11_platform)]
 use x11_dl::xlib_xcb::xcb_connection_t;
-#[cfg(wayland_platform)]
-use {memmap2::MmapOptions, std::os::unix::io::OwnedFd};
-
 use xkb::XKB_MOD_INVALID;
 use xkbcommon_dl::{
     self as xkb, xkb_keycode_t, xkb_keymap, xkb_keymap_compile_flags, xkb_keysym_t,
     xkb_layout_index_t, xkb_mod_index_t,
 };
+#[cfg(wayland_platform)]
+use {memmap2::MmapOptions, std::os::unix::io::OwnedFd};
 
 use crate::keyboard::{Key, KeyCode, KeyLocation, NamedKey, NativeKey, NativeKeyCode, PhysicalKey};
 #[cfg(x11_platform)]

src/platform_impl/linux/common/xkb/mod.rs

@@ -1,12 +1,11 @@
 use std::ops::Deref;
 use std::os::raw::c_char;
+#[cfg(wayland_platform)]
+use std::os::unix::io::OwnedFd;
 use std::ptr::{self, NonNull};
 use std::sync::atomic::{AtomicBool, Ordering};
 
-use crate::utils::Lazy;
 use smol_str::SmolStr;
-#[cfg(wayland_platform)]
-use std::os::unix::io::OwnedFd;
 use tracing::warn;
 use xkbcommon_dl::{
     self as xkb, xkb_compose_status, xkb_context, xkb_context_flags, xkbcommon_compose_handle,
@@ -18,16 +17,16 @@ use {x11_dl::xlib_xcb::xcb_connection_t, xkbcommon_dl::x11::xkbcommon_x11_handle
 use crate::event::{ElementState, KeyEvent};
 use crate::keyboard::{Key, KeyLocation};
 use crate::platform_impl::KeyEventExtra;
+use crate::utils::Lazy;
 
 mod compose;
 mod keymap;
 mod state;
 
 use compose::{ComposeStatus, XkbComposeState, XkbComposeTable};
-use keymap::XkbKeymap;
-
 #[cfg(x11_platform)]
 pub use keymap::raw_keycode_to_physicalkey;
+use keymap::XkbKeymap;
 pub use keymap::{physicalkey_to_scancode, scancode_to_physicalkey};
 pub use state::XkbState;
 

src/platform_impl/linux/mod.rs

@@ -4,6 +4,7 @@
 compile_error!("Please select a feature to build for unix: `x11`, `wayland`");
 
 use std::collections::VecDeque;
+use std::num::{NonZeroU16, NonZeroU32};
 use std::os::unix::io::{AsFd, AsRawFd, BorrowedFd, RawFd};
 use std::sync::Arc;
 use std::time::Duration;
@@ -11,31 +12,29 @@ use std::{env, fmt};
 #[cfg(x11_platform)]
 use std::{ffi::CStr, mem::MaybeUninit, os::raw::*, sync::Mutex};
 
-#[cfg(x11_platform)]
-use crate::utils::Lazy;
 use smol_str::SmolStr;
 
+pub(crate) use self::common::xkb::{physicalkey_to_scancode, scancode_to_physicalkey};
 #[cfg(x11_platform)]
 use self::x11::{X11Error, XConnection, XError, XNotSupported};
+use crate::application::ApplicationHandler;
+pub(crate) use crate::cursor::OnlyCursorImageSource as PlatformCustomCursorSource;
 use crate::dpi::{PhysicalPosition, PhysicalSize, Position, Size};
-use crate::error::{EventLoopError, ExternalError, NotSupportedError, OsError as RootOsError};
-use crate::event_loop::{
-    ActiveEventLoop as RootELW, AsyncRequestSerial, ControlFlow, DeviceEvents, EventLoopClosed,
-};
+use crate::error::{EventLoopError, ExternalError, NotSupportedError};
+use crate::event_loop::{ActiveEventLoop, AsyncRequestSerial};
 use crate::icon::Icon;
+pub(crate) use crate::icon::RgbaIcon as PlatformIcon;
 use crate::keyboard::Key;
 use crate::platform::pump_events::PumpStatus;
 #[cfg(x11_platform)]
 use crate::platform::x11::{WindowType as XWindowType, XlibErrorHook};
-use crate::window::{
-    ActivationToken, Cursor, CursorGrabMode, CustomCursor, CustomCursorSource, ImePurpose,
-    ResizeDirection, Theme, UserAttentionType, WindowAttributes, WindowButtons, WindowLevel,
-};
-
-pub(crate) use self::common::xkb::{physicalkey_to_scancode, scancode_to_physicalkey};
-pub(crate) use crate::cursor::OnlyCursorImageSource as PlatformCustomCursorSource;
-pub(crate) use crate::icon::RgbaIcon as PlatformIcon;
 pub(crate) use crate::platform_impl::Fullscreen;
+#[cfg(x11_platform)]
+use crate::utils::Lazy;
+use crate::window::{
+    ActivationToken, Cursor, CursorGrabMode, ImePurpose, ResizeDirection, Theme, UserAttentionType,
+    WindowButtons, WindowLevel,
+};
 
 pub(crate) mod common;
 #[cfg(wayland_platform)]
@@ -69,7 +68,7 @@ impl ApplicationName {
     }
 }
 
-#[derive(Clone, Debug)]
+#[derive(Clone, Debug, PartialEq)]
 pub struct PlatformSpecificWindowAttributes {
     pub name: Option<ApplicationName>,
     pub activation_token: Option<ActivationToken>,
@@ -77,7 +76,7 @@ pub struct PlatformSpecificWindowAttributes {
     pub x11: X11WindowAttributes,
 }
 
-#[derive(Clone, Debug)]
+#[derive(Clone, Debug, PartialEq)]
 #[cfg(x11_platform)]
 pub struct X11WindowAttributes {
     pub visual_id: Option<x11rb::protocol::xproto::Visualid>,
@@ -157,7 +156,7 @@ impl From<u64> for WindowId {
 }
 
 impl WindowId {
-    pub const unsafe fn dummy() -> Self {
+    pub const fn dummy() -> Self {
         Self(0)
     }
 }
@@ -171,15 +170,32 @@ pub enum DeviceId {
 }
 
 impl DeviceId {
-    pub const unsafe fn dummy() -> Self {
+    pub const fn dummy() -> Self {
         #[cfg(wayland_platform)]
-        return DeviceId::Wayland(unsafe { wayland::DeviceId::dummy() });
+        return DeviceId::Wayland(wayland::DeviceId::dummy());
         #[cfg(all(not(wayland_platform), x11_platform))]
-        return DeviceId::X(unsafe { x11::DeviceId::dummy() });
+        return DeviceId::X(x11::DeviceId::dummy());
     }
 }
 
-#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord)]
+#[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub enum FingerId {
+    #[cfg(x11_platform)]
+    X(x11::FingerId),
+    #[cfg(wayland_platform)]
+    Wayland(wayland::FingerId),
+}
+
+impl FingerId {
+    pub const fn dummy() -> Self {
+        #[cfg(wayland_platform)]
+        return FingerId::Wayland(wayland::FingerId::dummy());
+        #[cfg(all(not(wayland_platform), x11_platform))]
+        return FingerId::X(x11::FingerId::dummy());
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash, PartialOrd, Ord)]
 pub enum MonitorHandle {
     #[cfg(x11_platform)]
     X(x11::MonitorHandle),
@@ -227,25 +243,20 @@ impl MonitorHandle {
     }
 
     #[inline]
-    pub fn size(&self) -> PhysicalSize<u32> {
-        x11_or_wayland!(match self; MonitorHandle(m) => m.size())
-    }
-
-    #[inline]
-    pub fn position(&self) -> PhysicalPosition<i32> {
+    pub fn position(&self) -> Option<PhysicalPosition<i32>> {
         x11_or_wayland!(match self; MonitorHandle(m) => m.position())
     }
 
-    #[inline]
-    pub fn refresh_rate_millihertz(&self) -> Option<u32> {
-        x11_or_wayland!(match self; MonitorHandle(m) => m.refresh_rate_millihertz())
-    }
-
     #[inline]
     pub fn scale_factor(&self) -> f64 {
         x11_or_wayland!(match self; MonitorHandle(m) => m.scale_factor() as _)
     }
 
+    #[inline]
+    pub fn current_video_mode(&self) -> Option<VideoModeHandle> {
+        x11_or_wayland!(match self; MonitorHandle(m) => m.current_video_mode())
+    }
+
     #[inline]
     pub fn video_modes(&self) -> Box<dyn Iterator<Item = VideoModeHandle>> {
         x11_or_wayland!(match self; MonitorHandle(m) => Box::new(m.video_modes()))
@@ -267,12 +278,12 @@ impl VideoModeHandle {
     }
 
     #[inline]
-    pub fn bit_depth(&self) -> u16 {
+    pub fn bit_depth(&self) -> Option<NonZeroU16> {
         x11_or_wayland!(match self; VideoModeHandle(m) => m.bit_depth())
     }
 
     #[inline]
-    pub fn refresh_rate_millihertz(&self) -> u32 {
+    pub fn refresh_rate_millihertz(&self) -> Option<NonZeroU32> {
         x11_or_wayland!(match self; VideoModeHandle(m) => m.refresh_rate_millihertz())
     }
 
@@ -283,23 +294,6 @@ impl VideoModeHandle {
 }
 
 impl Window {
-    #[inline]
-    pub(crate) fn new(
-        window_target: &ActiveEventLoop,
-        attribs: WindowAttributes,
-    ) -> Result<Self, RootOsError> {
-        match *window_target {
-            #[cfg(wayland_platform)]
-            ActiveEventLoop::Wayland(ref window_target) => {
-                wayland::Window::new(window_target, attribs).map(Window::Wayland)
-            },
-            #[cfg(x11_platform)]
-            ActiveEventLoop::X(ref window_target) => {
-                x11::Window::new(window_target, attribs).map(Window::X)
-            },
-        }
-    }
-
     pub(crate) fn maybe_queue_on_main(&self, f: impl FnOnce(&Self) + Send + 'static) {
         f(self)
     }
@@ -571,24 +565,6 @@ impl Window {
         Some(x11_or_wayland!(match self; Window(w) => w.primary_monitor()?; as MonitorHandle))
     }
 
-    #[cfg(feature = "rwh_04")]
-    #[inline]
-    pub fn raw_window_handle_rwh_04(&self) -> rwh_04::RawWindowHandle {
-        x11_or_wayland!(match self; Window(window) => window.raw_window_handle_rwh_04())
-    }
-
-    #[cfg(feature = "rwh_05")]
-    #[inline]
-    pub fn raw_window_handle_rwh_05(&self) -> rwh_05::RawWindowHandle {
-        x11_or_wayland!(match self; Window(window) => window.raw_window_handle_rwh_05())
-    }
-
-    #[cfg(feature = "rwh_05")]
-    #[inline]
-    pub fn raw_display_handle_rwh_05(&self) -> rwh_05::RawDisplayHandle {
-        x11_or_wayland!(match self; Window(window) => window.raw_display_handle_rwh_05())
-    }
-
     #[cfg(feature = "rwh_06")]
     #[inline]
     pub fn raw_window_handle_rwh_06(&self) -> Result<rwh_06::RawWindowHandle, rwh_06::HandleError> {
@@ -692,27 +668,22 @@ unsafe extern "C" fn x_error_callback(
     0
 }
 
-pub enum EventLoop<T: 'static> {
+pub enum EventLoop {
     #[cfg(wayland_platform)]
-    Wayland(Box<wayland::EventLoop<T>>),
+    Wayland(Box<wayland::EventLoop>),
     #[cfg(x11_platform)]
-    X(x11::EventLoop<T>),
+    X(x11::EventLoop),
 }
 
-pub enum EventLoopProxy<T: 'static> {
+#[derive(Clone)]
+pub enum EventLoopProxy {
     #[cfg(x11_platform)]
-    X(x11::EventLoopProxy<T>),
+    X(x11::EventLoopProxy),
     #[cfg(wayland_platform)]
-    Wayland(wayland::EventLoopProxy<T>),
+    Wayland(wayland::EventLoopProxy),
 }
 
-impl<T: 'static> Clone for EventLoopProxy<T> {
-    fn clone(&self) -> Self {
-        x11_or_wayland!(match self; EventLoopProxy(proxy) => proxy.clone(); as EventLoopProxy)
-    }
-}
-
-impl<T: 'static> EventLoop<T> {
+impl EventLoop {
     pub(crate) fn new(
         attributes: &PlatformSpecificEventLoopAttributes,
     ) -> Result<Self, EventLoopError> {
@@ -771,12 +742,12 @@ impl<T: 'static> EventLoop<T> {
     }
 
     #[cfg(wayland_platform)]
-    fn new_wayland_any_thread() -> Result<EventLoop<T>, EventLoopError> {
+    fn new_wayland_any_thread() -> Result<EventLoop, EventLoopError> {
         wayland::EventLoop::new().map(|evlp| EventLoop::Wayland(Box::new(evlp)))
     }
 
     #[cfg(x11_platform)]
-    fn new_x11_any_thread() -> Result<EventLoop<T>, EventLoopError> {
+    fn new_x11_any_thread() -> Result<EventLoop, EventLoopError> {
         let xconn = match X11_BACKEND.lock().unwrap().as_ref() {
             Ok(xconn) => xconn.clone(),
             Err(_) => return Err(EventLoopError::NotSupported(NotSupportedError::new())),
@@ -785,153 +756,55 @@ impl<T: 'static> EventLoop<T> {
         Ok(EventLoop::X(x11::EventLoop::new(xconn)))
     }
 
-    pub fn create_proxy(&self) -> EventLoopProxy<T> {
-        x11_or_wayland!(match self; EventLoop(evlp) => evlp.create_proxy(); as EventLoopProxy)
-    }
-
-    pub fn run<F>(mut self, callback: F) -> Result<(), EventLoopError>
-    where
-        F: FnMut(crate::event::Event<T>, &RootELW),
-    {
-        self.run_on_demand(callback)
-    }
-
-    pub fn run_on_demand<F>(&mut self, callback: F) -> Result<(), EventLoopError>
-    where
-        F: FnMut(crate::event::Event<T>, &RootELW),
-    {
-        x11_or_wayland!(match self; EventLoop(evlp) => evlp.run_on_demand(callback))
-    }
-
-    pub fn pump_events<F>(&mut self, timeout: Option<Duration>, callback: F) -> PumpStatus
-    where
-        F: FnMut(crate::event::Event<T>, &RootELW),
-    {
-        x11_or_wayland!(match self; EventLoop(evlp) => evlp.pump_events(timeout, callback))
-    }
-
-    pub fn window_target(&self) -> &crate::event_loop::ActiveEventLoop {
-        x11_or_wayland!(match self; EventLoop(evlp) => evlp.window_target())
-    }
-}
-
-impl<T> AsFd for EventLoop<T> {
-    fn as_fd(&self) -> BorrowedFd<'_> {
-        x11_or_wayland!(match self; EventLoop(evlp) => evlp.as_fd())
-    }
-}
-
-impl<T> AsRawFd for EventLoop<T> {
-    fn as_raw_fd(&self) -> RawFd {
-        x11_or_wayland!(match self; EventLoop(evlp) => evlp.as_raw_fd())
-    }
-}
-
-impl<T: 'static> EventLoopProxy<T> {
-    pub fn send_event(&self, event: T) -> Result<(), EventLoopClosed<T>> {
-        x11_or_wayland!(match self; EventLoopProxy(proxy) => proxy.send_event(event))
-    }
-}
-
-pub enum ActiveEventLoop {
-    #[cfg(wayland_platform)]
-    Wayland(wayland::ActiveEventLoop),
-    #[cfg(x11_platform)]
-    X(x11::ActiveEventLoop),
-}
-
-impl ActiveEventLoop {
     #[inline]
     pub fn is_wayland(&self) -> bool {
         match *self {
             #[cfg(wayland_platform)]
-            ActiveEventLoop::Wayland(_) => true,
+            EventLoop::Wayland(_) => true,
             #[cfg(x11_platform)]
             _ => false,
         }
     }
 
-    pub fn create_custom_cursor(&self, cursor: CustomCursorSource) -> CustomCursor {
-        x11_or_wayland!(match self; ActiveEventLoop(evlp) => evlp.create_custom_cursor(cursor))
+    pub fn run_app<A: ApplicationHandler>(self, app: A) -> Result<(), EventLoopError> {
+        x11_or_wayland!(match self; EventLoop(evlp) => evlp.run_app(app))
     }
 
-    #[inline]
-    pub fn available_monitors(&self) -> VecDeque<MonitorHandle> {
-        match *self {
-            #[cfg(wayland_platform)]
-            ActiveEventLoop::Wayland(ref evlp) => {
-                evlp.available_monitors().map(MonitorHandle::Wayland).collect()
-            },
-            #[cfg(x11_platform)]
-            ActiveEventLoop::X(ref evlp) => {
-                evlp.available_monitors().map(MonitorHandle::X).collect()
-            },
-        }
+    pub fn run_app_on_demand<A: ApplicationHandler>(
+        &mut self,
+        app: A,
+    ) -> Result<(), EventLoopError> {
+        x11_or_wayland!(match self; EventLoop(evlp) => evlp.run_app_on_demand(app))
     }
 
-    #[inline]
-    pub fn primary_monitor(&self) -> Option<MonitorHandle> {
-        Some(
-            x11_or_wayland!(match self; ActiveEventLoop(evlp) => evlp.primary_monitor()?; as MonitorHandle),
-        )
+    pub fn pump_app_events<A: ApplicationHandler>(
+        &mut self,
+        timeout: Option<Duration>,
+        app: A,
+    ) -> PumpStatus {
+        x11_or_wayland!(match self; EventLoop(evlp) => evlp.pump_app_events(timeout, app))
     }
 
-    #[inline]
-    pub fn listen_device_events(&self, allowed: DeviceEvents) {
-        x11_or_wayland!(match self; Self(evlp) => evlp.listen_device_events(allowed))
+    pub fn window_target(&self) -> &dyn ActiveEventLoop {
+        x11_or_wayland!(match self; EventLoop(evlp) => evlp.window_target())
     }
+}
 
-    #[cfg(feature = "rwh_05")]
-    #[inline]
-    pub fn raw_display_handle_rwh_05(&self) -> rwh_05::RawDisplayHandle {
-        x11_or_wayland!(match self; Self(evlp) => evlp.raw_display_handle_rwh_05())
+impl AsFd for EventLoop {
+    fn as_fd(&self) -> BorrowedFd<'_> {
+        x11_or_wayland!(match self; EventLoop(evlp) => evlp.as_fd())
     }
+}
 
-    #[cfg(feature = "rwh_06")]
-    #[inline]
-    pub fn raw_display_handle_rwh_06(
-        &self,
-    ) -> Result<rwh_06::RawDisplayHandle, rwh_06::HandleError> {
-        x11_or_wayland!(match self; Self(evlp) => evlp.raw_display_handle_rwh_06())
+impl AsRawFd for EventLoop {
+    fn as_raw_fd(&self) -> RawFd {
+        x11_or_wayland!(match self; EventLoop(evlp) => evlp.as_raw_fd())
     }
+}
 
-    pub(crate) fn set_control_flow(&self, control_flow: ControlFlow) {
-        x11_or_wayland!(match self; Self(evlp) => evlp.set_control_flow(control_flow))
-    }
-
-    pub(crate) fn control_flow(&self) -> ControlFlow {
-        x11_or_wayland!(match self; Self(evlp) => evlp.control_flow())
-    }
-
-    pub(crate) fn clear_exit(&self) {
-        x11_or_wayland!(match self; Self(evlp) => evlp.clear_exit())
-    }
-
-    pub(crate) fn exit(&self) {
-        x11_or_wayland!(match self; Self(evlp) => evlp.exit())
-    }
-
-    pub(crate) fn exiting(&self) -> bool {
-        x11_or_wayland!(match self; Self(evlp) => evlp.exiting())
-    }
-
-    pub(crate) fn owned_display_handle(&self) -> OwnedDisplayHandle {
-        match self {
-            #[cfg(x11_platform)]
-            Self::X(conn) => OwnedDisplayHandle::X(conn.x_connection().clone()),
-            #[cfg(wayland_platform)]
-            Self::Wayland(conn) => OwnedDisplayHandle::Wayland(conn.connection.clone()),
-        }
-    }
-
-    #[allow(dead_code)]
-    fn set_exit_code(&self, code: i32) {
-        x11_or_wayland!(match self; Self(evlp) => evlp.set_exit_code(code))
-    }
-
-    #[allow(dead_code)]
-    fn exit_code(&self) -> Option<i32> {
-        x11_or_wayland!(match self; Self(evlp) => evlp.exit_code())
+impl EventLoopProxy {
+    pub fn wake_up(&self) {
+        x11_or_wayland!(match self; EventLoopProxy(proxy) => proxy.wake_up())
     }
 }
 
@@ -945,29 +818,6 @@ pub(crate) enum OwnedDisplayHandle {
 }
 
 impl OwnedDisplayHandle {
-    #[cfg(feature = "rwh_05")]
-    #[inline]
-    pub fn raw_display_handle_rwh_05(&self) -> rwh_05::RawDisplayHandle {
-        match self {
-            #[cfg(x11_platform)]
-            Self::X(xconn) => {
-                let mut xlib_handle = rwh_05::XlibDisplayHandle::empty();
-                xlib_handle.display = xconn.display.cast();
-                xlib_handle.screen = xconn.default_screen_index() as _;
-                xlib_handle.into()
-            },
-
-            #[cfg(wayland_platform)]
-            Self::Wayland(conn) => {
-                use sctk::reexports::client::Proxy;
-
-                let mut wayland_handle = rwh_05::WaylandDisplayHandle::empty();
-                wayland_handle.display = conn.display().id().as_ptr() as *mut _;
-                wayland_handle.into()
-            },
-        }
-    }
-
     #[cfg(feature = "rwh_06")]
     #[inline]
     pub fn raw_display_handle_rwh_06(
@@ -996,6 +846,21 @@ impl OwnedDisplayHandle {
     }
 }
 
+impl PartialEq for OwnedDisplayHandle {
+    fn eq(&self, other: &Self) -> bool {
+        match (self, other) {
+            #[cfg(x11_platform)]
+            (Self::X(this), Self::X(other)) => Arc::as_ptr(this).eq(&Arc::as_ptr(other)),
+            #[cfg(wayland_platform)]
+            (Self::Wayland(this), Self::Wayland(other)) => this.eq(other),
+            #[cfg(all(x11_platform, wayland_platform))]
+            _ => false,
+        }
+    }
+}
+
+impl Eq for OwnedDisplayHandle {}
+
 /// Returns the minimum `Option<Duration>`, taking into account that `None`
 /// equates to an infinite timeout, not a zero timeout (so can't just use
 /// `Option::min`)

src/platform_impl/linux/wayland/event_loop/mod.rs

@@ -1,11 +1,10 @@
 //! The event-loop routines.
 
+use std::any::Any;
 use std::cell::{Cell, RefCell};
 use std::io::Result as IOResult;
-use std::marker::PhantomData;
 use std::mem;
 use std::os::unix::io::{AsFd, AsRawFd, BorrowedFd, RawFd};
-use std::rc::Rc;
 use std::sync::atomic::Ordering;
 use std::sync::{Arc, Mutex};
 use std::time::{Duration, Instant};
@@ -14,17 +13,16 @@ use sctk::reexports::calloop::Error as CalloopError;
 use sctk::reexports::calloop_wayland_source::WaylandSource;
 use sctk::reexports::client::{globals, Connection, QueueHandle};
 
+use crate::application::ApplicationHandler;
 use crate::cursor::OnlyCursorImage;
 use crate::dpi::LogicalSize;
-use crate::error::{EventLoopError, OsError as RootOsError};
+use crate::error::{EventLoopError, ExternalError, OsError as RootOsError};
 use crate::event::{Event, InnerSizeWriter, StartCause, WindowEvent};
 use crate::event_loop::{ActiveEventLoop as RootActiveEventLoop, ControlFlow, DeviceEvents};
 use crate::platform::pump_events::PumpStatus;
 use crate::platform_impl::platform::min_timeout;
-use crate::platform_impl::{
-    ActiveEventLoop as PlatformActiveEventLoop, OsError, PlatformCustomCursor,
-};
-use crate::window::{CustomCursor as RootCustomCursor, CustomCursorSource};
+use crate::platform_impl::{OsError, PlatformCustomCursor};
+use crate::window::{CustomCursor as RootCustomCursor, CustomCursorSource, Theme};
 
 mod proxy;
 pub mod sink;
@@ -39,7 +37,7 @@ use super::{logical_to_physical_rounded, DeviceId, WaylandError, WindowId};
 type WaylandDispatcher = calloop::Dispatcher<'static, WaylandSource<WinitState>, WinitState>;
 
 /// The Wayland event loop.
-pub struct EventLoop<T: 'static> {
+pub struct EventLoop {
     /// Has `run` or `run_on_demand` been called or a call to `pump_events` that starts the loop
     loop_running: bool,
 
@@ -47,14 +45,6 @@ pub struct EventLoop<T: 'static> {
     compositor_updates: Vec<WindowCompositorUpdate>,
     window_ids: Vec<WindowId>,
 
-    /// Sender of user events.
-    user_events_sender: calloop::channel::Sender<T>,
-
-    // XXX can't remove RefCell out of here, unless we can plumb generics into the `Window`, which
-    // we don't really want, since it'll break public API by a lot.
-    /// Pending events from the user.
-    pending_user_events: Rc<RefCell<Vec<T>>>,
-
     /// The Wayland dispatcher to has raw access to the queue when needed, such as
     /// when creating a new window.
     wayland_dispatcher: WaylandDispatcher,
@@ -63,15 +53,15 @@ pub struct EventLoop<T: 'static> {
     connection: Connection,
 
     /// Event loop window target.
-    window_target: RootActiveEventLoop,
+    pub(crate) active_event_loop: ActiveEventLoop,
 
     // XXX drop after everything else, just to be safe.
     /// Calloop's event loop.
     event_loop: calloop::EventLoop<'static, WinitState>,
 }
 
-impl<T: 'static> EventLoop<T> {
-    pub fn new() -> Result<EventLoop<T>, EventLoopError> {
+impl EventLoop {
+    pub fn new() -> Result<EventLoop, EventLoopError> {
         macro_rules! map_err {
             ($e:expr, $err:expr) => {
                 $e.map_err(|error| os_error!($err(error).into()))
@@ -114,16 +104,12 @@ impl<T: 'static> EventLoop<T> {
         )?;
 
         // Setup the user proxy.
-        let pending_user_events = Rc::new(RefCell::new(Vec::new()));
-        let pending_user_events_clone = pending_user_events.clone();
-        let (user_events_sender, user_events_channel) = calloop::channel::channel();
+        let (ping, ping_source) = calloop::ping::make_ping().unwrap();
         let result = event_loop
             .handle()
-            .insert_source(user_events_channel, move |event, _, winit_state: &mut WinitState| {
-                if let calloop::channel::Event::Msg(msg) = event {
-                    winit_state.dispatched_events = true;
-                    pending_user_events_clone.borrow_mut().push(msg);
-                }
+            .insert_source(ping_source, move |_, _, winit_state: &mut WinitState| {
+                winit_state.dispatched_events = true;
+                winit_state.proxy_wake_up = true;
             })
             .map_err(|error| error.error);
         map_err!(result, WaylandError::Calloop)?;
@@ -144,14 +130,16 @@ impl<T: 'static> EventLoop<T> {
             .map_err(|error| error.error);
         map_err!(result, WaylandError::Calloop)?;
 
-        let window_target = ActiveEventLoop {
+        let active_event_loop = ActiveEventLoop {
             connection: connection.clone(),
             wayland_dispatcher: wayland_dispatcher.clone(),
             event_loop_awakener,
+            event_loop_proxy: EventLoopProxy::new(ping),
             queue_handle,
             control_flow: Cell::new(ControlFlow::default()),
             exit: Cell::new(None),
             state: RefCell::new(winit_state),
+            wayland_callback: Default::default(),
         };
 
         let event_loop = Self {
@@ -161,24 +149,24 @@ impl<T: 'static> EventLoop<T> {
             window_ids: Vec::new(),
             connection,
             wayland_dispatcher,
-            user_events_sender,
-            pending_user_events,
             event_loop,
-            window_target: RootActiveEventLoop {
-                p: PlatformActiveEventLoop::Wayland(window_target),
-                _marker: PhantomData,
-            },
+            active_event_loop,
         };
 
         Ok(event_loop)
     }
 
-    pub fn run_on_demand<F>(&mut self, mut event_handler: F) -> Result<(), EventLoopError>
-    where
-        F: FnMut(Event<T>, &RootActiveEventLoop),
-    {
+    pub fn run_app<A: ApplicationHandler>(mut self, app: A) -> Result<(), EventLoopError> {
+        self.run_app_on_demand(app)
+    }
+
+    pub fn run_app_on_demand<A: ApplicationHandler>(
+        &mut self,
+        mut app: A,
+    ) -> Result<(), EventLoopError> {
+        self.active_event_loop.clear_exit();
         let exit = loop {
-            match self.pump_events(None, &mut event_handler) {
+            match self.pump_app_events(None, &mut app) {
                 PumpStatus::Exit(0) => {
                     break Ok(());
                 },
@@ -200,26 +188,27 @@ impl<T: 'static> EventLoop<T> {
         exit
     }
 
-    pub fn pump_events<F>(&mut self, timeout: Option<Duration>, mut callback: F) -> PumpStatus
-    where
-        F: FnMut(Event<T>, &RootActiveEventLoop),
-    {
+    pub fn pump_app_events<A: ApplicationHandler>(
+        &mut self,
+        timeout: Option<Duration>,
+        mut app: A,
+    ) -> PumpStatus {
         if !self.loop_running {
             self.loop_running = true;
 
             // Run the initial loop iteration.
-            self.single_iteration(&mut callback, StartCause::Init);
+            self.single_iteration(&mut app, StartCause::Init);
         }
 
         // Consider the possibility that the `StartCause::Init` iteration could
         // request to Exit.
         if !self.exiting() {
-            self.poll_events_with_timeout(timeout, &mut callback);
+            self.poll_events_with_timeout(timeout, &mut app);
         }
         if let Some(code) = self.exit_code() {
             self.loop_running = false;
 
-            callback(Event::LoopExiting, self.window_target());
+            app.exiting(&self.active_event_loop);
 
             PumpStatus::Exit(code)
         } else {
@@ -227,10 +216,11 @@ impl<T: 'static> EventLoop<T> {
         }
     }
 
-    pub fn poll_events_with_timeout<F>(&mut self, mut timeout: Option<Duration>, mut callback: F)
-    where
-        F: FnMut(Event<T>, &RootActiveEventLoop),
-    {
+    fn poll_events_with_timeout<A: ApplicationHandler>(
+        &mut self,
+        mut timeout: Option<Duration>,
+        app: &mut A,
+    ) {
         let cause = loop {
             let start = Instant::now();
 
@@ -292,13 +282,10 @@ impl<T: 'static> EventLoop<T> {
             break cause;
         };
 
-        self.single_iteration(&mut callback, cause);
+        self.single_iteration(app, cause);
     }
 
-    fn single_iteration<F>(&mut self, callback: &mut F, cause: StartCause)
-    where
-        F: FnMut(Event<T>, &RootActiveEventLoop),
-    {
+    fn single_iteration<A: ApplicationHandler>(&mut self, app: &mut A, cause: StartCause) {
         // NOTE currently just indented to simplify the diff
 
         // We retain these grow-only scratch buffers as part of the EventLoop
@@ -309,18 +296,21 @@ impl<T: 'static> EventLoop<T> {
         let mut buffer_sink = std::mem::take(&mut self.buffer_sink);
         let mut window_ids = std::mem::take(&mut self.window_ids);
 
-        callback(Event::NewEvents(cause), &self.window_target);
+        app.new_events(&self.active_event_loop, cause);
 
-        // NB: For consistency all platforms must emit a 'resumed' event even though Wayland
-        // applications don't themselves have a formal suspend/resume lifecycle.
-        if cause == StartCause::Init {
-            callback(Event::Resumed, &self.window_target);
+        if let Some(callback) = self.active_event_loop.wayland_callback.get() {
+            callback(app);
         }
 
-        // Handle pending user events. We don't need back buffer, since we can't dispatch
-        // user events indirectly via callback to the user.
-        for user_event in self.pending_user_events.borrow_mut().drain(..) {
-            callback(Event::UserEvent(user_event), &self.window_target);
+        // NB: For consistency all platforms must call `can_create_surfaces` even though Wayland
+        // applications don't themselves have a formal surface destroy/create lifecycle.
+        if cause == StartCause::Init {
+            app.can_create_surfaces(&self.active_event_loop);
+        }
+
+        // Indicate user wake up.
+        if self.with_state(|state| mem::take(&mut state.proxy_wake_up)) {
+            app.proxy_wake_up(&self.active_event_loop);
         }
 
         // Drain the pending compositor updates.
@@ -341,18 +331,13 @@ impl<T: 'static> EventLoop<T> {
                 let old_physical_size = physical_size;
 
                 let new_inner_size = Arc::new(Mutex::new(physical_size));
-                callback(
-                    Event::WindowEvent {
-                        window_id: crate::window::WindowId(window_id),
-                        event: WindowEvent::ScaleFactorChanged {
-                            scale_factor,
-                            inner_size_writer: InnerSizeWriter::new(Arc::downgrade(
-                                &new_inner_size,
-                            )),
-                        },
-                    },
-                    &self.window_target,
-                );
+                let root_window_id = crate::window::WindowId(window_id);
+                let event = WindowEvent::ScaleFactorChanged {
+                    scale_factor,
+                    inner_size_writer: InnerSizeWriter::new(Arc::downgrade(&new_inner_size)),
+                };
+
+                app.window_event(&self.active_event_loop, root_window_id, event);
 
                 let physical_size = *new_inner_size.lock().unwrap();
                 drop(new_inner_size);
@@ -395,23 +380,14 @@ impl<T: 'static> EventLoop<T> {
                     size
                 });
 
-                callback(
-                    Event::WindowEvent {
-                        window_id: crate::window::WindowId(window_id),
-                        event: WindowEvent::Resized(physical_size),
-                    },
-                    &self.window_target,
-                );
+                let window_id = crate::window::WindowId(window_id);
+                let event = WindowEvent::Resized(physical_size);
+                app.window_event(&self.active_event_loop, window_id, event);
             }
 
             if compositor_update.close_window {
-                callback(
-                    Event::WindowEvent {
-                        window_id: crate::window::WindowId(window_id),
-                        event: WindowEvent::CloseRequested,
-                    },
-                    &self.window_target,
-                );
+                let window_id = crate::window::WindowId(window_id);
+                app.window_event(&self.active_event_loop, window_id, WindowEvent::CloseRequested);
             }
         }
 
@@ -420,8 +396,15 @@ impl<T: 'static> EventLoop<T> {
             buffer_sink.append(&mut state.window_events_sink.lock().unwrap());
         });
         for event in buffer_sink.drain() {
-            let event = event.map_nonuser_event().unwrap();
-            callback(event, &self.window_target);
+            match event {
+                Event::WindowEvent { window_id, event } => {
+                    app.window_event(&self.active_event_loop, window_id, event)
+                },
+                Event::DeviceEvent { device_id, event } => {
+                    app.device_event(&self.active_event_loop, device_id, event)
+                },
+                _ => unreachable!("event which is neither device nor window event."),
+            }
         }
 
         // Handle non-synthetic events.
@@ -429,8 +412,15 @@ impl<T: 'static> EventLoop<T> {
             buffer_sink.append(&mut state.events_sink);
         });
         for event in buffer_sink.drain() {
-            let event = event.map_nonuser_event().unwrap();
-            callback(event, &self.window_target);
+            match event {
+                Event::WindowEvent { window_id, event } => {
+                    app.window_event(&self.active_event_loop, window_id, event)
+                },
+                Event::DeviceEvent { device_id, event } => {
+                    app.device_event(&self.active_event_loop, device_id, event)
+                },
+                _ => unreachable!("event which is neither device nor window event."),
+            }
         }
 
         // Collect the window ids
@@ -466,10 +456,8 @@ impl<T: 'static> EventLoop<T> {
             });
 
             if let Some(event) = event {
-                callback(
-                    Event::WindowEvent { window_id: crate::window::WindowId(*window_id), event },
-                    &self.window_target,
-                );
+                let window_id = crate::window::WindowId(*window_id);
+                app.window_event(&self.active_event_loop, window_id, event);
             }
         }
 
@@ -479,7 +467,7 @@ impl<T: 'static> EventLoop<T> {
         });
 
         // This is always the last event we dispatch before poll again
-        callback(Event::AboutToWait, &self.window_target);
+        app.about_to_wait(&self.active_event_loop);
 
         // Update the window frames and schedule redraws.
         let mut wake_up = false;
@@ -508,13 +496,7 @@ impl<T: 'static> EventLoop<T> {
         // If the user draws from the `AboutToWait` this is likely not required, however
         // we can't do much about it.
         if wake_up {
-            match &self.window_target.p {
-                PlatformActiveEventLoop::Wayland(window_target) => {
-                    window_target.event_loop_awakener.ping();
-                },
-                #[cfg(x11_platform)]
-                PlatformActiveEventLoop::X(_) => unreachable!(),
-            }
+            self.active_event_loop.event_loop_awakener.ping();
         }
 
         std::mem::swap(&mut self.compositor_updates, &mut compositor_updates);
@@ -523,31 +505,17 @@ impl<T: 'static> EventLoop<T> {
     }
 
     #[inline]
-    pub fn create_proxy(&self) -> EventLoopProxy<T> {
-        EventLoopProxy::new(self.user_events_sender.clone())
-    }
-
-    #[inline]
-    pub fn window_target(&self) -> &RootActiveEventLoop {
-        &self.window_target
+    pub fn window_target(&self) -> &dyn RootActiveEventLoop {
+        &self.active_event_loop
     }
 
     fn with_state<'a, U: 'a, F: FnOnce(&'a mut WinitState) -> U>(&'a mut self, callback: F) -> U {
-        let state = match &mut self.window_target.p {
-            PlatformActiveEventLoop::Wayland(window_target) => window_target.state.get_mut(),
-            #[cfg(x11_platform)]
-            _ => unreachable!(),
-        };
-
+        let state = self.active_event_loop.state.get_mut();
         callback(state)
     }
 
     fn loop_dispatch<D: Into<Option<std::time::Duration>>>(&mut self, timeout: D) -> IOResult<()> {
-        let state = match &mut self.window_target.p {
-            PlatformActiveEventLoop::Wayland(window_target) => window_target.state.get_mut(),
-            #[cfg(feature = "x11")]
-            _ => unreachable!(),
-        };
+        let state = &mut self.active_event_loop.state.get_mut();
 
         self.event_loop.dispatch(timeout, state).map_err(|error| {
             tracing::error!("Error dispatching event loop: {}", error);
@@ -556,11 +524,7 @@ impl<T: 'static> EventLoop<T> {
     }
 
     fn roundtrip(&mut self) -> Result<usize, RootOsError> {
-        let state = match &mut self.window_target.p {
-            PlatformActiveEventLoop::Wayland(window_target) => window_target.state.get_mut(),
-            #[cfg(feature = "x11")]
-            _ => unreachable!(),
-        };
+        let state = &mut self.active_event_loop.state.get_mut();
 
         let mut wayland_source = self.wayland_dispatcher.as_source_mut();
         let event_queue = wayland_source.queue();
@@ -570,35 +534,38 @@ impl<T: 'static> EventLoop<T> {
     }
 
     fn control_flow(&self) -> ControlFlow {
-        self.window_target.p.control_flow()
+        self.active_event_loop.control_flow()
     }
 
     fn exiting(&self) -> bool {
-        self.window_target.p.exiting()
+        self.active_event_loop.exiting()
     }
 
     fn set_exit_code(&self, code: i32) {
-        self.window_target.p.set_exit_code(code)
+        self.active_event_loop.set_exit_code(code)
     }
 
     fn exit_code(&self) -> Option<i32> {
-        self.window_target.p.exit_code()
+        self.active_event_loop.exit_code()
     }
 }
 
-impl<T> AsFd for EventLoop<T> {
+impl AsFd for EventLoop {
     fn as_fd(&self) -> BorrowedFd<'_> {
         self.event_loop.as_fd()
     }
 }
 
-impl<T> AsRawFd for EventLoop<T> {
+impl AsRawFd for EventLoop {
     fn as_raw_fd(&self) -> RawFd {
         self.event_loop.as_raw_fd()
     }
 }
 
 pub struct ActiveEventLoop {
+    /// Event loop proxy
+    event_loop_proxy: EventLoopProxy,
+
     /// The event loop wakeup source.
     pub event_loop_awakener: calloop::ping::Ping,
 
@@ -620,67 +587,119 @@ pub struct ActiveEventLoop {
 
     /// Connection to the wayland server.
     pub connection: Connection,
+
+    pub wayland_callback: Cell<Option<fn(&mut dyn ApplicationHandler)>>,
 }
 
-impl ActiveEventLoop {
-    pub(crate) fn set_control_flow(&self, control_flow: ControlFlow) {
-        self.control_flow.set(control_flow)
-    }
-
-    pub(crate) fn control_flow(&self) -> ControlFlow {
-        self.control_flow.get()
-    }
-
-    pub(crate) fn exit(&self) {
-        self.exit.set(Some(0))
-    }
-
-    pub(crate) fn clear_exit(&self) {
-        self.exit.set(None)
-    }
-
-    pub(crate) fn exiting(&self) -> bool {
-        self.exit.get().is_some()
-    }
-
-    pub(crate) fn set_exit_code(&self, code: i32) {
-        self.exit.set(Some(code))
-    }
-
-    pub(crate) fn exit_code(&self) -> Option<i32> {
-        self.exit.get()
-    }
-
-    #[inline]
-    pub fn listen_device_events(&self, _allowed: DeviceEvents) {}
-
-    pub(crate) fn create_custom_cursor(&self, cursor: CustomCursorSource) -> RootCustomCursor {
-        RootCustomCursor {
-            inner: PlatformCustomCursor::Wayland(OnlyCursorImage(Arc::from(cursor.inner.0))),
+impl RootActiveEventLoop for ActiveEventLoop {
+    fn create_proxy(&self) -> crate::event_loop::EventLoopProxy {
+        crate::event_loop::EventLoopProxy {
+            event_loop_proxy: crate::platform_impl::EventLoopProxy::Wayland(
+                self.event_loop_proxy.clone(),
+            ),
         }
     }
 
-    #[cfg(feature = "rwh_05")]
-    #[inline]
-    pub fn raw_display_handle_rwh_05(&self) -> rwh_05::RawDisplayHandle {
-        use sctk::reexports::client::Proxy;
+    fn set_control_flow(&self, control_flow: ControlFlow) {
+        self.control_flow.set(control_flow)
+    }
 
-        let mut display_handle = rwh_05::WaylandDisplayHandle::empty();
-        display_handle.display = self.connection.display().id().as_ptr() as *mut _;
-        rwh_05::RawDisplayHandle::Wayland(display_handle)
+    fn control_flow(&self) -> ControlFlow {
+        self.control_flow.get()
+    }
+
+    fn exit(&self) {
+        self.exit.set(Some(0))
+    }
+
+    fn exiting(&self) -> bool {
+        self.exit.get().is_some()
+    }
+
+    #[inline]
+    fn listen_device_events(&self, _allowed: DeviceEvents) {}
+
+    fn create_custom_cursor(
+        &self,
+        cursor: CustomCursorSource,
+    ) -> Result<RootCustomCursor, ExternalError> {
+        Ok(RootCustomCursor {
+            inner: PlatformCustomCursor::Wayland(OnlyCursorImage(Arc::from(cursor.inner.0))),
+        })
+    }
+
+    #[inline]
+    fn system_theme(&self) -> Option<Theme> {
+        None
+    }
+
+    fn create_window(
+        &self,
+        window_attributes: crate::window::WindowAttributes,
+    ) -> Result<crate::window::Window, RootOsError> {
+        let window = crate::platform_impl::wayland::Window::new(self, window_attributes)?;
+        let window = crate::platform_impl::Window::Wayland(window);
+        Ok(crate::window::Window { window })
+    }
+
+    fn available_monitors(&self) -> Box<dyn Iterator<Item = crate::monitor::MonitorHandle>> {
+        Box::new(
+            self.state
+                .borrow()
+                .output_state
+                .outputs()
+                .map(crate::platform_impl::wayland::output::MonitorHandle::new)
+                .map(crate::platform_impl::MonitorHandle::Wayland)
+                .map(|inner| crate::monitor::MonitorHandle { inner }),
+        )
+    }
+
+    fn primary_monitor(&self) -> Option<crate::monitor::MonitorHandle> {
+        // There's no primary monitor on Wayland.
+        None
+    }
+
+    fn owned_display_handle(&self) -> crate::event_loop::OwnedDisplayHandle {
+        crate::event_loop::OwnedDisplayHandle {
+            platform: crate::platform_impl::OwnedDisplayHandle::Wayland(self.connection.clone()),
+        }
+    }
+
+    #[inline(always)]
+    fn as_any(&self) -> &dyn Any {
+        self
     }
 
     #[cfg(feature = "rwh_06")]
-    #[inline]
-    pub fn raw_display_handle_rwh_06(
-        &self,
-    ) -> Result<rwh_06::RawDisplayHandle, rwh_06::HandleError> {
-        use sctk::reexports::client::Proxy;
-
-        Ok(rwh_06::WaylandDisplayHandle::new({
-            let ptr = self.connection.display().id().as_ptr();
-            std::ptr::NonNull::new(ptr as *mut _).expect("wl_display should never be null")
-        })
-        .into())
+    fn rwh_06_handle(&self) -> &dyn rwh_06::HasDisplayHandle {
+        self
+    }
+}
+
+impl ActiveEventLoop {
+    fn clear_exit(&self) {
+        self.exit.set(None)
+    }
+
+    fn set_exit_code(&self, code: i32) {
+        self.exit.set(Some(code))
+    }
+
+    fn exit_code(&self) -> Option<i32> {
+        self.exit.get()
+    }
+}
+
+#[cfg(feature = "rwh_06")]
+impl rwh_06::HasDisplayHandle for ActiveEventLoop {
+    fn display_handle(&self) -> Result<rwh_06::DisplayHandle<'_>, rwh_06::HandleError> {
+        use sctk::reexports::client::Proxy;
+
+        let raw = rwh_06::WaylandDisplayHandle::new({
+            let ptr = self.connection.display().id().as_ptr();
+            std::ptr::NonNull::new(ptr as *mut _).expect("wl_display should never be null")
+        });
+
+        Ok(unsafe { rwh_06::DisplayHandle::borrow_raw(raw.into()) })
     }
 }

src/platform_impl/linux/wayland/event_loop/proxy.rs

@@ -1,28 +1,19 @@
 //! An event loop proxy.
 
-use std::sync::mpsc::SendError;
-
-use sctk::reexports::calloop::channel::Sender;
-
-use crate::event_loop::EventLoopClosed;
+use sctk::reexports::calloop::ping::Ping;
 
 /// A handle that can be sent across the threads and used to wake up the `EventLoop`.
-pub struct EventLoopProxy<T: 'static> {
-    user_events_sender: Sender<T>,
+#[derive(Clone)]
+pub struct EventLoopProxy {
+    ping: Ping,
 }
 
-impl<T: 'static> Clone for EventLoopProxy<T> {
-    fn clone(&self) -> Self {
-        EventLoopProxy { user_events_sender: self.user_events_sender.clone() }
-    }
-}
-
-impl<T: 'static> EventLoopProxy<T> {
-    pub fn new(user_events_sender: Sender<T>) -> Self {
-        Self { user_events_sender }
+impl EventLoopProxy {
+    pub fn new(ping: Ping) -> Self {
+        Self { ping }
     }
 
-    pub fn send_event(&self, event: T) -> Result<(), EventLoopClosed<T>> {
-        self.user_events_sender.send(event).map_err(|SendError(error)| EventLoopClosed(error))
+    pub fn wake_up(&self) {
+        self.ping.ping();
     }
 }

src/platform_impl/linux/wayland/event_loop/sink.rs

@@ -2,17 +2,16 @@
 
 use std::vec::Drain;
 
+use super::{DeviceId, WindowId};
 use crate::event::{DeviceEvent, DeviceId as RootDeviceId, Event, WindowEvent};
 use crate::platform_impl::platform::DeviceId as PlatformDeviceId;
 use crate::window::WindowId as RootWindowId;
 
-use super::{DeviceId, WindowId};
-
 /// An event loop's sink to deliver events from the Wayland event callbacks
 /// to the winit's user.
 #[derive(Default)]
 pub struct EventSink {
-    pub window_events: Vec<Event<()>>,
+    pub(crate) window_events: Vec<Event>,
 }
 
 impl EventSink {
@@ -47,7 +46,7 @@ impl EventSink {
     }
 
     #[inline]
-    pub fn drain(&mut self) -> Drain<'_, Event<()>> {
+    pub(crate) fn drain(&mut self) -> Drain<'_, Event> {
         self.window_events.drain(..)
     }
 }

src/platform_impl/linux/wayland/mod.rs

@@ -1,20 +1,18 @@
-#![cfg(wayland_platform)]
-
 //! Winit's Wayland backend.
 
 use std::fmt::Display;
 use std::sync::Arc;
 
+pub use event_loop::{ActiveEventLoop, EventLoop, EventLoopProxy};
+pub use output::{MonitorHandle, VideoModeHandle};
 use sctk::reexports::client::globals::{BindError, GlobalError};
 use sctk::reexports::client::protocol::wl_surface::WlSurface;
 use sctk::reexports::client::{self, ConnectError, DispatchError, Proxy};
+pub use window::Window;
 
 pub(super) use crate::cursor::OnlyCursorImage as CustomCursor;
 use crate::dpi::{LogicalSize, PhysicalSize};
 pub use crate::platform_impl::platform::{OsError, WindowId};
-pub use event_loop::{ActiveEventLoop, EventLoop, EventLoopProxy};
-pub use output::{MonitorHandle, VideoModeHandle};
-pub use window::Window;
 
 mod event_loop;
 mod output;
@@ -68,11 +66,20 @@ impl From<WaylandError> for OsError {
 pub struct DeviceId;
 
 impl DeviceId {
-    pub const unsafe fn dummy() -> Self {
+    pub const fn dummy() -> Self {
         DeviceId
     }
 }
 
+#[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub struct FingerId(i32);
+
+impl FingerId {
+    pub const fn dummy() -> Self {
+        FingerId(0)
+    }
+}
+
 /// Get the WindowId out of the surface.
 #[inline]
 fn make_wid(surface: &WlSurface) -> WindowId {

src/platform_impl/linux/wayland/output.rs

@@ -1,26 +1,12 @@
+use std::num::{NonZeroU16, NonZeroU32};
+
+use sctk::output::{Mode, OutputData};
 use sctk::reexports::client::protocol::wl_output::WlOutput;
 use sctk::reexports::client::Proxy;
 
-use sctk::output::OutputData;
-
 use crate::dpi::{LogicalPosition, PhysicalPosition, PhysicalSize};
 use crate::platform_impl::platform::VideoModeHandle as PlatformVideoModeHandle;
 
-use super::event_loop::ActiveEventLoop;
-
-impl ActiveEventLoop {
-    #[inline]
-    pub fn available_monitors(&self) -> impl Iterator<Item = MonitorHandle> {
-        self.state.borrow().output_state.outputs().map(MonitorHandle::new)
-    }
-
-    #[inline]
-    pub fn primary_monitor(&self) -> Option<MonitorHandle> {
-        // There's no primary monitor on Wayland.
-        None
-    }
-}
-
 #[derive(Clone, Debug)]
 pub struct MonitorHandle {
     pub(crate) proxy: WlOutput,
@@ -45,23 +31,9 @@ impl MonitorHandle {
     }
 
     #[inline]
-    pub fn size(&self) -> PhysicalSize<u32> {
+    pub fn position(&self) -> Option<PhysicalPosition<i32>> {
         let output_data = self.proxy.data::<OutputData>().unwrap();
-        let dimensions = output_data.with_output_info(|info| {
-            info.modes.iter().find_map(|mode| mode.current.then_some(mode.dimensions))
-        });
-
-        match dimensions {
-            Some((width, height)) => (width as u32, height as u32),
-            _ => (0, 0),
-        }
-        .into()
-    }
-
-    #[inline]
-    pub fn position(&self) -> PhysicalPosition<i32> {
-        let output_data = self.proxy.data::<OutputData>().unwrap();
-        output_data.with_output_info(|info| {
+        Some(output_data.with_output_info(|info| {
             info.logical_position.map_or_else(
                 || {
                     LogicalPosition::<i32>::from(info.location)
@@ -72,15 +44,7 @@ impl MonitorHandle {
                         .to_physical(info.scale_factor as f64)
                 },
             )
-        })
-    }
-
-    #[inline]
-    pub fn refresh_rate_millihertz(&self) -> Option<u32> {
-        let output_data = self.proxy.data::<OutputData>().unwrap();
-        output_data.with_output_info(|info| {
-            info.modes.iter().find_map(|mode| mode.current.then_some(mode.refresh_rate as u32))
-        })
+        }))
     }
 
     #[inline]
@@ -89,6 +53,18 @@ impl MonitorHandle {
         output_data.scale_factor()
     }
 
+    #[inline]
+    pub fn current_video_mode(&self) -> Option<PlatformVideoModeHandle> {
+        let output_data = self.proxy.data::<OutputData>().unwrap();
+        output_data.with_output_info(|info| {
+            let mode = info.modes.iter().find(|mode| mode.current).cloned();
+
+            mode.map(|mode| {
+                PlatformVideoModeHandle::Wayland(VideoModeHandle::new(self.clone(), mode))
+            })
+        })
+    }
+
     #[inline]
     pub fn video_modes(&self) -> impl Iterator<Item = PlatformVideoModeHandle> {
         let output_data = self.proxy.data::<OutputData>().unwrap();
@@ -97,12 +73,7 @@ impl MonitorHandle {
         let monitor = self.clone();
 
         modes.into_iter().map(move |mode| {
-            PlatformVideoModeHandle::Wayland(VideoModeHandle {
-                size: (mode.dimensions.0 as u32, mode.dimensions.1 as u32).into(),
-                refresh_rate_millihertz: mode.refresh_rate as u32,
-                bit_depth: 32,
-                monitor: monitor.clone(),
-            })
+            PlatformVideoModeHandle::Wayland(VideoModeHandle::new(monitor.clone(), mode))
         })
     }
 }
@@ -136,24 +107,31 @@ impl std::hash::Hash for MonitorHandle {
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub struct VideoModeHandle {
     pub(crate) size: PhysicalSize<u32>,
-    pub(crate) bit_depth: u16,
-    pub(crate) refresh_rate_millihertz: u32,
+    pub(crate) refresh_rate_millihertz: Option<NonZeroU32>,
     pub(crate) monitor: MonitorHandle,
 }
 
 impl VideoModeHandle {
+    fn new(monitor: MonitorHandle, mode: Mode) -> Self {
+        VideoModeHandle {
+            size: (mode.dimensions.0 as u32, mode.dimensions.1 as u32).into(),
+            refresh_rate_millihertz: NonZeroU32::new(mode.refresh_rate as u32),
+            monitor: monitor.clone(),
+        }
+    }
+
     #[inline]
     pub fn size(&self) -> PhysicalSize<u32> {
         self.size
     }
 
     #[inline]
-    pub fn bit_depth(&self) -> u16 {
-        self.bit_depth
+    pub fn bit_depth(&self) -> Option<NonZeroU16> {
+        None
     }
 
     #[inline]
-    pub fn refresh_rate_millihertz(&self) -> u32 {
+    pub fn refresh_rate_millihertz(&self) -> Option<NonZeroU32> {
         self.refresh_rate_millihertz
     }
 

src/platform_impl/linux/wayland/seat/keyboard/mod.rs

@@ -5,20 +5,17 @@ use std::time::Duration;
 
 use calloop::timer::{TimeoutAction, Timer};
 use calloop::{LoopHandle, RegistrationToken};
-use tracing::warn;
-
 use sctk::reexports::client::protocol::wl_keyboard::{
     Event as WlKeyboardEvent, KeyState as WlKeyState, KeymapFormat as WlKeymapFormat, WlKeyboard,
 };
 use sctk::reexports::client::protocol::wl_seat::WlSeat;
 use sctk::reexports::client::{Connection, Dispatch, Proxy, QueueHandle, WEnum};
+use tracing::warn;
 
 use crate::event::{ElementState, WindowEvent};
 use crate::keyboard::ModifiersState;
-
 use crate::platform_impl::common::xkb::Context;
 use crate::platform_impl::wayland::event_loop::sink::EventSink;
-use crate::platform_impl::wayland::seat::WinitSeatState;
 use crate::platform_impl::wayland::state::WinitState;
 use crate::platform_impl::wayland::{self, DeviceId, WindowId};
 
@@ -33,7 +30,17 @@ impl Dispatch<WlKeyboard, KeyboardData, WinitState> for WinitState {
     ) {
         let seat_state = match state.seats.get_mut(&data.seat.id()) {
             Some(seat_state) => seat_state,
-            None => return,
+            None => {
+                warn!("Received keyboard event {event:?} without seat");
+                return;
+            },
+        };
+        let keyboard_state = match seat_state.keyboard_state.as_mut() {
+            Some(keyboard_state) => keyboard_state,
+            None => {
+                warn!("Received keyboard event {event:?} without keyboard");
+                return;
+            },
         };
 
         match event {
@@ -43,7 +50,7 @@ impl Dispatch<WlKeyboard, KeyboardData, WinitState> for WinitState {
                         warn!("non-xkb compatible keymap")
                     },
                     WlKeymapFormat::XkbV1 => {
-                        let context = &mut seat_state.keyboard_state.as_mut().unwrap().xkb_context;
+                        let context = &mut keyboard_state.xkb_context;
                         context.set_keymap_from_fd(fd, size as usize);
                     },
                     _ => unreachable!(),
@@ -67,7 +74,6 @@ impl Dispatch<WlKeyboard, KeyboardData, WinitState> for WinitState {
                 };
 
                 // Drop the repeat, if there were any.
-                let keyboard_state = seat_state.keyboard_state.as_mut().unwrap();
                 keyboard_state.current_repeat = None;
                 if let Some(token) = keyboard_state.repeat_token.take() {
                     keyboard_state.loop_handle.remove(token);
@@ -93,7 +99,6 @@ impl Dispatch<WlKeyboard, KeyboardData, WinitState> for WinitState {
 
                 // NOTE: we should drop the repeat regardless whethere it was for the present
                 // window of for the window which just went gone.
-                let keyboard_state = seat_state.keyboard_state.as_mut().unwrap();
                 keyboard_state.current_repeat = None;
                 if let Some(token) = keyboard_state.repeat_token.take() {
                     keyboard_state.loop_handle.remove(token);
@@ -128,7 +133,7 @@ impl Dispatch<WlKeyboard, KeyboardData, WinitState> for WinitState {
                 let key = key + 8;
 
                 key_input(
-                    seat_state,
+                    keyboard_state,
                     &mut state.events_sink,
                     data,
                     key,
@@ -136,7 +141,6 @@ impl Dispatch<WlKeyboard, KeyboardData, WinitState> for WinitState {
                     false,
                 );
 
-                let keyboard_state = seat_state.keyboard_state.as_mut().unwrap();
                 let delay = match keyboard_state.repeat_info {
                     RepeatInfo::Repeat { delay, .. } => delay,
                     RepeatInfo::Disable => return,
@@ -163,18 +167,25 @@ impl Dispatch<WlKeyboard, KeyboardData, WinitState> for WinitState {
                         state.dispatched_events = true;
 
                         let data = wl_keyboard.data::<KeyboardData>().unwrap();
-                        let seat_state = state.seats.get_mut(&data.seat.id()).unwrap();
+                        let seat_state = match state.seats.get_mut(&data.seat.id()) {
+                            Some(seat_state) => seat_state,
+                            None => return TimeoutAction::Drop,
+                        };
 
-                        // NOTE: The removed on event source is batched, but key change to
-                        // `None` is instant.
-                        let repeat_keycode =
-                            match seat_state.keyboard_state.as_ref().unwrap().current_repeat {
-                                Some(repeat_keycode) => repeat_keycode,
-                                None => return TimeoutAction::Drop,
-                            };
+                        let keyboard_state = match seat_state.keyboard_state.as_mut() {
+                            Some(keyboard_state) => keyboard_state,
+                            None => return TimeoutAction::Drop,
+                        };
+
+                        // NOTE: The removed on event source is batched, but key change to `None`
+                        // is instant.
+                        let repeat_keycode = match keyboard_state.current_repeat {
+                            Some(repeat_keycode) => repeat_keycode,
+                            None => return TimeoutAction::Drop,
+                        };
 
                         key_input(
-                            seat_state,
+                            keyboard_state,
                             &mut state.events_sink,
                             data,
                             repeat_keycode,
@@ -183,7 +194,7 @@ impl Dispatch<WlKeyboard, KeyboardData, WinitState> for WinitState {
                         );
 
                         // NOTE: the gap could change dynamically while repeat is going.
-                        match seat_state.keyboard_state.as_ref().unwrap().repeat_info {
+                        match keyboard_state.repeat_info {
                             RepeatInfo::Repeat { gap, .. } => TimeoutAction::ToDuration(gap),
                             RepeatInfo::Disable => TimeoutAction::Drop,
                         }
@@ -194,7 +205,7 @@ impl Dispatch<WlKeyboard, KeyboardData, WinitState> for WinitState {
                 let key = key + 8;
 
                 key_input(
-                    seat_state,
+                    keyboard_state,
                     &mut state.events_sink,
                     data,
                     key,
@@ -202,7 +213,6 @@ impl Dispatch<WlKeyboard, KeyboardData, WinitState> for WinitState {
                     false,
                 );
 
-                let keyboard_state = seat_state.keyboard_state.as_mut().unwrap();
                 if keyboard_state.repeat_info != RepeatInfo::Disable
                     && keyboard_state.xkb_context.keymap_mut().unwrap().key_repeats(key)
                     && Some(key) == keyboard_state.current_repeat
@@ -216,7 +226,7 @@ impl Dispatch<WlKeyboard, KeyboardData, WinitState> for WinitState {
             WlKeyboardEvent::Modifiers {
                 mods_depressed, mods_latched, mods_locked, group, ..
             } => {
-                let xkb_context = &mut seat_state.keyboard_state.as_mut().unwrap().xkb_context;
+                let xkb_context = &mut keyboard_state.xkb_context;
                 let xkb_state = match xkb_context.state_mut() {
                     Some(state) => state,
                     None => return,
@@ -240,7 +250,6 @@ impl Dispatch<WlKeyboard, KeyboardData, WinitState> for WinitState {
                 );
             },
             WlKeyboardEvent::RepeatInfo { rate, delay } => {
-                let keyboard_state = seat_state.keyboard_state.as_mut().unwrap();
                 keyboard_state.repeat_info = if rate == 0 {
                     // Stop the repeat once we get a disable event.
                     keyboard_state.current_repeat = None;
@@ -348,7 +357,7 @@ impl KeyboardData {
 }
 
 fn key_input(
-    seat_state: &mut WinitSeatState,
+    keyboard_state: &mut KeyboardState,
     event_sink: &mut EventSink,
     data: &KeyboardData,
     keycode: u32,
@@ -360,8 +369,6 @@ fn key_input(
         None => return,
     };
 
-    let keyboard_state = seat_state.keyboard_state.as_mut().unwrap();
-
     let device_id = crate::event::DeviceId(crate::platform_impl::DeviceId::Wayland(DeviceId));
     if let Some(mut key_context) = keyboard_state.xkb_context.key_context() {
         let event = key_context.process_key_event(keycode, state, repeat);

src/platform_impl/linux/wayland/seat/mod.rs

@@ -3,16 +3,15 @@
 use std::sync::Arc;
 
 use ahash::AHashMap;
-
 use sctk::reexports::client::backend::ObjectId;
 use sctk::reexports::client::protocol::wl_seat::WlSeat;
 use sctk::reexports::client::protocol::wl_touch::WlTouch;
 use sctk::reexports::client::{Connection, Proxy, QueueHandle};
 use sctk::reexports::protocols::wp::relative_pointer::zv1::client::zwp_relative_pointer_v1::ZwpRelativePointerV1;
 use sctk::reexports::protocols::wp::text_input::zv3::client::zwp_text_input_v3::ZwpTextInputV3;
-
 use sctk::seat::pointer::{ThemeSpec, ThemedPointer};
 use sctk::seat::{Capability as SeatCapability, SeatHandler, SeatState};
+use tracing::warn;
 
 use crate::event::WindowEvent;
 use crate::keyboard::ModifiersState;
@@ -23,12 +22,11 @@ mod pointer;
 mod text_input;
 mod touch;
 
+use keyboard::{KeyboardData, KeyboardState};
 pub use pointer::relative_pointer::RelativePointerState;
 pub use pointer::{PointerConstraintsState, WinitPointerData, WinitPointerDataExt};
-pub use text_input::{TextInputState, ZwpTextInputV3Ext};
-
-use keyboard::{KeyboardData, KeyboardState};
 use text_input::TextInputData;
+pub use text_input::{TextInputState, ZwpTextInputV3Ext};
 use touch::TouchPoint;
 
 #[derive(Debug, Default)]
@@ -76,7 +74,13 @@ impl SeatHandler for WinitState {
         seat: WlSeat,
         capability: SeatCapability,
     ) {
-        let seat_state = self.seats.get_mut(&seat.id()).unwrap();
+        let seat_state = match self.seats.get_mut(&seat.id()) {
+            Some(seat_state) => seat_state,
+            None => {
+                warn!("Received wl_seat::new_capability for unknown seat");
+                return;
+            },
+        };
 
         match capability {
             SeatCapability::Touch if seat_state.touch.is_none() => {
@@ -139,7 +143,13 @@ impl SeatHandler for WinitState {
         seat: WlSeat,
         capability: SeatCapability,
     ) {
-        let seat_state = self.seats.get_mut(&seat.id()).unwrap();
+        let seat_state = match self.seats.get_mut(&seat.id()) {
+            Some(seat_state) => seat_state,
+            None => {
+                warn!("Received wl_seat::remove_capability for unknown seat");
+                return;
+            },
+        };
 
         if let Some(text_input) = seat_state.text_input.take() {
             text_input.destroy();