Reduce the use of custom cfgs in examples

The `x11_platform`/`wayland_platform` cfgs remain (those are a lot more
involved, so it might still makes sense to use them for clarity).

.github/workflows/ci.yml

@@ -136,7 +136,7 @@ jobs:
 
     - name: Generate lockfile
       # Also updates the crates.io index
-      run: cargo generate-lockfile && cargo update -p smol_str --precise 0.3.2
+      run: cargo generate-lockfile && cargo update -p smol_str --precise 0.3.2 && cargo update -p unicode-segmentation --precise 1.12.0
 
     - name: Install GCC Multilib
       if: (matrix.platform.os == 'ubuntu-latest') && contains(matrix.platform.target, 'i686')

Cargo.toml

@@ -60,7 +60,6 @@ objc2-core-foundation = { version = "0.3.2", default-features = false }
 objc2-core-graphics = { version = "0.3.2", default-features = false }
 objc2-core-video = { version = "0.3.2", default-features = false }
 objc2-foundation = { version = "0.3.2", default-features = false }
-objc2-quartz-core = { version = "0.3.2", default-features = false }
 objc2-ui-kit = { version = "0.3.2", default-features = false }
 
 # Windows dependencies.

clippy.toml

@@ -1,4 +1,11 @@
 # Using allow-invalid because this is platform-specific code
+disallowed-macros = [
+    { path = "std::print", reason = "works badly on web", replacement = "tracing::info" },
+    { path = "std::println", reason = "works badly on web", replacement = "tracing::info" },
+    { path = "std::eprint", reason = "works badly on web", replacement = "tracing::error" },
+    { path = "std::eprintln", reason = "works badly on web", replacement = "tracing::error" },
+    { path = "std::dbg", reason = "leftover debugging aid, remove it or use tracing" },
+]
 disallowed-methods = [
     { allow-invalid = true, 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." },
     { allow-invalid = true, path = "objc2_app_kit::NSWindow::setFrameTopLeftPoint", reason = "Not sufficient when working with Winit's coordinate system, use `flip_window_screen_coordinates` instead" },

deny.toml

@@ -43,6 +43,9 @@ skip = [
     { crate = "bitflags@1", reason = "the ecosystem is in the process of migrating" },
     { crate = "rustix@0.38", reason = "the ecosystem is in the process of migrating" },
     { crate = "linux-raw-sys@0.4", reason = "the ecosystem is in the process of migrating" },
+    { crate = "jni-sys@0.3", reason = "uses the semver trick to depend on v0.4, but `ndk` hasn't been updated to v0.4 yet" },
+    { crate = "thiserror@1.0", reason = "dep of `ndk` crate, yet to be updated" },
+    { crate = "thiserror-impl@1.0", reason = "dep of `thiserror`" },
 ]
 wildcards = "allow" # at least until https://github.com/EmbarkStudios/cargo-deny/issues/241 is fixed
 
@@ -51,9 +54,7 @@ include-archives = true
 interpreted = "deny"
 
 [[bans.build.bypass]]
-allow = [
-    { path = "generate-bindings.sh", checksum = "268ec23248218d779e33853cdc60e2985e70214ff004716cd734270de1f6b561" },
-]
+allow-globs = ["android-games-sdk/import-games-sdk.sh"]
 crate = "android-activity"
 
 [[bans.build.bypass]]

winit-android/src/keycodes.rs

@@ -109,6 +109,7 @@ pub fn to_physical_key(keycode: Keycode) -> PhysicalKey {
         Keycode::MediaStop => KeyCode::MediaStop,
         Keycode::MediaNext => KeyCode::MediaTrackNext,
         Keycode::MediaPrevious => KeyCode::MediaTrackPrevious,
+        Keycode::MediaEject => KeyCode::Eject,
 
         Keycode::Plus => KeyCode::Equal,
         Keycode::Minus => KeyCode::Minus,
@@ -131,7 +132,11 @@ pub fn to_physical_key(keycode: Keycode) -> PhysicalKey {
         // These are exactly the same
         Keycode::ScrollLock => KeyCode::ScrollLock,
 
+        Keycode::Eisu => KeyCode::Lang2,
+        Keycode::Muhenkan => KeyCode::NonConvert,
+        Keycode::Henkan => KeyCode::Convert,
         Keycode::Yen => KeyCode::IntlYen,
+        Keycode::Ro => KeyCode::IntlRo,
         Keycode::Kana => KeyCode::Lang1,
         Keycode::KatakanaHiragana => KeyCode::KanaMode,
 
@@ -154,6 +159,14 @@ pub fn to_physical_key(keycode: Keycode) -> PhysicalKey {
         Keycode::Sleep => KeyCode::Sleep, // what about SoftSleep?
         Keycode::Wakeup => KeyCode::WakeUp,
 
+        Keycode::CapsLock => KeyCode::CapsLock,
+        Keycode::Help => KeyCode::Help,
+
+        Keycode::Back => KeyCode::BrowserBack,
+        Keycode::Forward => KeyCode::BrowserForward,
+        Keycode::Refresh => KeyCode::BrowserRefresh,
+        Keycode::Search => KeyCode::BrowserSearch,
+
         keycode => return PhysicalKey::Unidentified(NativeKeyCode::Android(keycode.into())),
     })
 }

winit-appkit/Cargo.toml

@@ -107,8 +107,7 @@ objc2-foundation = { workspace = true, features = [
     "NSThread",
     "NSValue",
 ] }
-objc2-quartz-core = { workspace = true, features = ["std", "CABase"] }
-winit-common = { workspace = true, features = ["core-foundation", "event-handler"] }
+winit-common = { workspace = true, features = ["core-foundation", "event-handler", "foundation"] }
 
 [dev-dependencies]
 winit.workspace = true

winit-appkit/src/app.rs

@@ -1,14 +1,15 @@
 #![allow(clippy::unnecessary_cast)]
 
 use std::cell::Cell;
-use std::mem;
 use std::rc::Rc;
+use std::{mem, ptr};
 
 use dispatch2::MainThreadBound;
 use objc2::runtime::{Imp, Sel};
 use objc2::sel;
 use objc2_app_kit::{NSApplication, NSEvent, NSEventModifierFlags, NSEventType};
 use objc2_foundation::MainThreadMarker;
+use tracing::trace_span;
 use winit_core::event::{DeviceEvent, ElementState};
 
 use super::app_state::AppState;
@@ -21,6 +22,10 @@ static ORIGINAL: MainThreadBound<Cell<Option<SendEvent>>> = {
 };
 
 extern "C-unwind" fn send_event(app: &NSApplication, sel: Sel, event: &NSEvent) {
+    // This can be a bit noisy, since `event` is fairly large. Note that you can use
+    // `RUST_LOG='trace,winit_appkit::app=warn'` if you're debugging and want TRACE-level logs but
+    // not this.
+    let _entered = trace_span!("sendEvent:", ?event).entered();
     let mtm = MainThreadMarker::from(app);
 
     // Normally, holding Cmd + any key never sends us a `keyUp` event for that key.
@@ -75,9 +80,7 @@ pub(crate) fn override_send_event(global_app: &NSApplication) {
     let overridden = unsafe { mem::transmute::<SendEvent, Imp>(send_event) };
 
     // If we've already overridden the method, don't do anything.
-    // FIXME(madsmtm): Use `std::ptr::fn_addr_eq` (Rust 1.85) once available in MSRV.
-    #[allow(unknown_lints, unpredictable_function_pointer_comparisons)]
-    if overridden == method.implementation() {
+    if ptr::fn_addr_eq(overridden, method.implementation()) {
         return;
     }
 
@@ -98,7 +101,6 @@ pub(crate) fn override_send_event(global_app: &NSApplication) {
 }
 
 fn maybe_dispatch_device_event(app_state: &Rc<AppState>, event: &NSEvent) {
-    let time = app_state.event_time(event);
     let event_type = event.r#type();
     #[allow(non_upper_case_globals)]
     match event_type {
@@ -111,7 +113,7 @@ fn maybe_dispatch_device_event(app_state: &Rc<AppState>, event: &NSEvent) {
 
             if delta_x != 0.0 || delta_y != 0.0 {
                 app_state.maybe_queue_with_handler(move |app, event_loop| {
-                    app.device_event(event_loop, None, time, DeviceEvent::PointerMotion {
+                    app.device_event(event_loop, None, DeviceEvent::PointerMotion {
                         delta: (delta_x, delta_y),
                     });
                 });
@@ -120,7 +122,7 @@ fn maybe_dispatch_device_event(app_state: &Rc<AppState>, event: &NSEvent) {
         NSEventType::LeftMouseDown | NSEventType::RightMouseDown | NSEventType::OtherMouseDown => {
             let button = event.buttonNumber() as u32;
             app_state.maybe_queue_with_handler(move |app, event_loop| {
-                app.device_event(event_loop, None, time, DeviceEvent::Button {
+                app.device_event(event_loop, None, DeviceEvent::Button {
                     button,
                     state: ElementState::Pressed,
                 });
@@ -129,7 +131,7 @@ fn maybe_dispatch_device_event(app_state: &Rc<AppState>, event: &NSEvent) {
         NSEventType::LeftMouseUp | NSEventType::RightMouseUp | NSEventType::OtherMouseUp => {
             let button = event.buttonNumber() as u32;
             app_state.maybe_queue_with_handler(move |app, event_loop| {
-                app.device_event(event_loop, None, time, DeviceEvent::Button {
+                app.device_event(event_loop, None, DeviceEvent::Button {
                     button,
                     state: ElementState::Released,
                 });

winit-appkit/src/app_state.rs

@@ -2,14 +2,12 @@ use std::cell::{Cell, OnceCell, RefCell};
 use std::mem;
 use std::rc::Rc;
 use std::sync::Arc;
-use std::time::{Duration, Instant};
+use std::time::Instant;
 
 use dispatch2::MainThreadBound;
 use objc2::MainThreadMarker;
-use objc2_app_kit::{NSApplication, NSApplicationActivationPolicy, NSEvent, NSRunningApplication};
-use objc2_foundation::{NSNotification, NSTimeInterval};
-use objc2_quartz_core::CACurrentMediaTime;
-use tracing::warn;
+use objc2_app_kit::{NSApplication, NSApplicationActivationPolicy, NSRunningApplication};
+use objc2_foundation::NSNotification;
 use winit_common::core_foundation::{EventLoopProxy, MainRunLoop};
 use winit_common::event_handler::EventHandler;
 use winit_core::application::ApplicationHandler;
@@ -45,8 +43,6 @@ pub(super) struct AppState {
     start_time: Cell<Option<Instant>>,
     wait_timeout: Cell<Option<Instant>>,
     pending_redraw: RefCell<Vec<WindowId>>,
-    startup_instant: Instant,
-    startup_timestamp: NSTimeInterval,
     // 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.
 }
@@ -67,17 +63,6 @@ impl AppState {
             Self::get(mtm).with_handler(|app, event_loop| app.proxy_wake_up(event_loop));
         }));
 
-        // Prime dylib caches etc.
-        let _ = CACurrentMediaTime();
-
-        // Find the current Rust timestamp.
-        let startup_instant = Instant::now();
-        // Find the timestamp
-        //
-        // `NSProcessInfo::processInfo().systemUptime()` needs the required reason manifest,
-        // `CACurrentMediaTime` (currently) doesn't, so we use that instead.
-        let startup_timestamp = CACurrentMediaTime();
-
         let this = Rc::new(Self {
             mtm,
             activation_policy,
@@ -98,8 +83,6 @@ impl AppState {
             start_time: Cell::new(None),
             wait_timeout: Cell::new(None),
             pending_redraw: RefCell::new(vec![]),
-            startup_instant,
-            startup_timestamp,
         });
 
         GLOBAL.get(mtm).set(this.clone()).ok().and(Some(this))
@@ -113,20 +96,9 @@ impl AppState {
             .clone()
     }
 
-    pub(crate) fn event_time(&self, event: &NSEvent) -> Instant {
-        if event.timestamp() == 0.0 {
-            warn!(?event, "got zero timestamp");
-            return Instant::now();
-        }
-        let duration_since_startup = event.timestamp() - self.startup_timestamp;
-        let duration_since_startup = Duration::from_secs_f64(duration_since_startup as f64);
-        self.startup_instant + duration_since_startup
-    }
-
     // NOTE: This notification will, globally, only be emitted once,
     // no matter how many `EventLoop`s the user creates.
     pub fn did_finish_launching(self: &Rc<Self>, _notification: &NSNotification) {
-        trace_scope!("NSApplicationDidFinishLaunchingNotification");
         self.is_launched.set(true);
 
         let app = NSApplication::sharedApplication(self.mtm);
@@ -181,7 +153,6 @@ impl AppState {
     }
 
     pub fn will_terminate(self: &Rc<Self>, _notification: &NSNotification) {
-        trace_scope!("NSApplicationWillTerminateNotification");
         let app = NSApplication::sharedApplication(self.mtm);
         notify_windows_of_exit(&app);
         self.event_handler.terminate();
@@ -274,12 +245,7 @@ impl AppState {
         // -> Don't go back into the event handler when our callstack originates from there
         if !self.event_handler.in_use() {
             self.with_handler(|app, event_loop| {
-                app.window_event(
-                    event_loop,
-                    window_id,
-                    Instant::now(),
-                    WindowEvent::RedrawRequested,
-                );
+                app.window_event(event_loop, window_id, WindowEvent::RedrawRequested);
             });
 
             // `pump_events` will request to stop immediately _after_ dispatching RedrawRequested
@@ -379,12 +345,7 @@ impl AppState {
         let redraw = mem::take(&mut *self.pending_redraw.borrow_mut());
         for window_id in redraw {
             self.with_handler(|app, event_loop| {
-                app.window_event(
-                    event_loop,
-                    window_id,
-                    Instant::now(),
-                    WindowEvent::RedrawRequested,
-                );
+                app.window_event(event_loop, window_id, WindowEvent::RedrawRequested);
             });
         }
         self.with_handler(|app, event_loop| {

winit-appkit/src/cursor.rs

@@ -5,7 +5,10 @@ use std::sync::OnceLock;
 use objc2::rc::Retained;
 use objc2::runtime::Sel;
 use objc2::{AllocAnyThread, ClassType, available, msg_send, sel};
-use objc2_app_kit::{NSBitmapImageRep, NSCursor, NSDeviceRGBColorSpace, NSImage};
+use objc2_app_kit::{
+    NSBitmapImageRep, NSCursor, NSCursorFrameResizeDirections, NSCursorFrameResizePosition,
+    NSDeviceRGBColorSpace, NSImage,
+};
 use objc2_foundation::{
     NSData, NSDictionary, NSNumber, NSObject, NSPoint, NSSize, NSString, ns_string,
 };
@@ -204,23 +207,155 @@ pub(crate) fn cursor_from_icon(icon: CursorIcon) -> Retained<NSCursor> {
         CursorIcon::NotAllowed | CursorIcon::NoDrop => NSCursor::operationNotAllowedCursor(),
         CursorIcon::ContextMenu => NSCursor::contextualMenuCursor(),
         CursorIcon::Crosshair => NSCursor::crosshairCursor(),
-        CursorIcon::EResize => NSCursor::resizeRightCursor(),
-        CursorIcon::NResize => NSCursor::resizeUpCursor(),
-        CursorIcon::WResize => NSCursor::resizeLeftCursor(),
-        CursorIcon::SResize => NSCursor::resizeDownCursor(),
-        CursorIcon::EwResize | CursorIcon::ColResize => NSCursor::resizeLeftRightCursor(),
-        CursorIcon::NsResize | CursorIcon::RowResize => NSCursor::resizeUpDownCursor(),
+        CursorIcon::EResize => {
+            if available!(macos = 15.0) {
+                NSCursor::frameResizeCursorFromPosition_inDirections(
+                    NSCursorFrameResizePosition::Right,
+                    NSCursorFrameResizeDirections::Outward,
+                )
+            } else {
+                NSCursor::resizeRightCursor()
+            }
+        },
+        CursorIcon::NResize => {
+            if available!(macos = 15.0) {
+                NSCursor::frameResizeCursorFromPosition_inDirections(
+                    NSCursorFrameResizePosition::Top,
+                    NSCursorFrameResizeDirections::Outward,
+                )
+            } else {
+                NSCursor::resizeUpCursor()
+            }
+        },
+        CursorIcon::WResize => {
+            if available!(macos = 15.0) {
+                NSCursor::frameResizeCursorFromPosition_inDirections(
+                    NSCursorFrameResizePosition::Left,
+                    NSCursorFrameResizeDirections::Outward,
+                )
+            } else {
+                NSCursor::resizeLeftCursor()
+            }
+        },
+        CursorIcon::SResize => {
+            if available!(macos = 15.0) {
+                NSCursor::frameResizeCursorFromPosition_inDirections(
+                    NSCursorFrameResizePosition::Bottom,
+                    NSCursorFrameResizeDirections::Outward,
+                )
+            } else {
+                NSCursor::resizeDownCursor()
+            }
+        },
+        CursorIcon::EwResize => {
+            if available!(macos = 15.0) {
+                NSCursor::frameResizeCursorFromPosition_inDirections(
+                    NSCursorFrameResizePosition::Right,
+                    NSCursorFrameResizeDirections::All,
+                )
+            } else {
+                NSCursor::resizeLeftRightCursor()
+            }
+        },
+        CursorIcon::NsResize => {
+            if available!(macos = 15.0) {
+                NSCursor::frameResizeCursorFromPosition_inDirections(
+                    NSCursorFrameResizePosition::Top,
+                    NSCursorFrameResizeDirections::All,
+                )
+            } else {
+                NSCursor::resizeUpDownCursor()
+            }
+        },
+        CursorIcon::NeResize => {
+            if available!(macos = 15.0) {
+                NSCursor::frameResizeCursorFromPosition_inDirections(
+                    NSCursorFrameResizePosition::TopRight,
+                    NSCursorFrameResizeDirections::Outward,
+                )
+            } else {
+                _windowResizeNorthEastCursor()
+            }
+        },
+        CursorIcon::NwResize => {
+            if available!(macos = 15.0) {
+                NSCursor::frameResizeCursorFromPosition_inDirections(
+                    NSCursorFrameResizePosition::TopLeft,
+                    NSCursorFrameResizeDirections::Outward,
+                )
+            } else {
+                _windowResizeNorthWestCursor()
+            }
+        },
+        CursorIcon::SeResize => {
+            if available!(macos = 15.0) {
+                NSCursor::frameResizeCursorFromPosition_inDirections(
+                    NSCursorFrameResizePosition::BottomRight,
+                    NSCursorFrameResizeDirections::Outward,
+                )
+            } else {
+                _windowResizeSouthEastCursor()
+            }
+        },
+        CursorIcon::SwResize => {
+            if available!(macos = 15.0) {
+                NSCursor::frameResizeCursorFromPosition_inDirections(
+                    NSCursorFrameResizePosition::BottomLeft,
+                    NSCursorFrameResizeDirections::Outward,
+                )
+            } else {
+                _windowResizeSouthWestCursor()
+            }
+        },
+        CursorIcon::NeswResize => {
+            if available!(macos = 15.0) {
+                NSCursor::frameResizeCursorFromPosition_inDirections(
+                    NSCursorFrameResizePosition::TopRight,
+                    NSCursorFrameResizeDirections::All,
+                )
+            } else {
+                _windowResizeNorthEastSouthWestCursor()
+            }
+        },
+        CursorIcon::NwseResize => {
+            if available!(macos = 15.0) {
+                NSCursor::frameResizeCursorFromPosition_inDirections(
+                    NSCursorFrameResizePosition::TopLeft,
+                    NSCursorFrameResizeDirections::All,
+                )
+            } else {
+                _windowResizeNorthWestSouthEastCursor()
+            }
+        },
+        CursorIcon::ColResize => {
+            if available!(macos = 15.0) {
+                NSCursor::columnResizeCursor()
+            } else {
+                NSCursor::resizeLeftRightCursor()
+            }
+        },
+        CursorIcon::RowResize => {
+            if available!(macos = 15.0) {
+                NSCursor::rowResizeCursor()
+            } else {
+                NSCursor::resizeUpDownCursor()
+            }
+        },
+        CursorIcon::ZoomIn => {
+            if available!(macos = 15.0) {
+                NSCursor::zoomInCursor()
+            } else {
+                _zoomInCursor()
+            }
+        },
+        CursorIcon::ZoomOut => {
+            if available!(macos = 15.0) {
+                NSCursor::zoomOutCursor()
+            } else {
+                _zoomOutCursor()
+            }
+        },
         CursorIcon::Help => _helpCursor(),
-        CursorIcon::ZoomIn if available!(macos = 15.0) => NSCursor::zoomInCursor(),
-        CursorIcon::ZoomIn => _zoomInCursor(),
-        CursorIcon::ZoomOut if available!(macos = 15.0) => NSCursor::zoomOutCursor(),
-        CursorIcon::ZoomOut => _zoomOutCursor(),
-        CursorIcon::NeResize => _windowResizeNorthEastCursor(),
-        CursorIcon::NwResize => _windowResizeNorthWestCursor(),
-        CursorIcon::SeResize => _windowResizeSouthEastCursor(),
-        CursorIcon::SwResize => _windowResizeSouthWestCursor(),
-        CursorIcon::NeswResize => _windowResizeNorthEastSouthWestCursor(),
-        CursorIcon::NwseResize => _windowResizeNorthWestSouthEastCursor(),
         // This is the wrong semantics for `Wait`, but it's the same as
         // what's used in Safari and Chrome.
         CursorIcon::Wait | CursorIcon::Progress => busyButClickableCursor(),

winit-appkit/src/event_loop.rs

@@ -12,7 +12,9 @@ use objc2_app_kit::{
 use objc2_core_foundation::{CFIndex, CFRunLoopActivity, kCFRunLoopCommonModes};
 use objc2_foundation::{NSNotificationCenter, NSObjectProtocol};
 use rwh_06::HasDisplayHandle;
-use winit_common::core_foundation::{MainRunLoop, MainRunLoopObserver};
+use tracing::debug_span;
+use winit_common::core_foundation::{MainRunLoop, MainRunLoopObserver, tracing_observers};
+use winit_common::foundation::create_observer;
 use winit_core::application::ApplicationHandler;
 use winit_core::cursor::{CustomCursor as CoreCustomCursor, CustomCursorSource};
 use winit_core::error::{EventLoopError, RequestError};
@@ -29,7 +31,6 @@ use super::app_state::AppState;
 use super::cursor::CustomCursor;
 use super::event::dummy_event;
 use super::monitor;
-use super::notification_center::create_observer;
 use crate::ActivationPolicy;
 use crate::window::Window;
 
@@ -152,6 +153,7 @@ pub struct EventLoop {
     _did_finish_launching_observer: Retained<ProtocolObject<dyn NSObjectProtocol>>,
     _will_terminate_observer: Retained<ProtocolObject<dyn NSObjectProtocol>>,
 
+    _tracing_observers: Option<(MainRunLoopObserver, MainRunLoopObserver)>,
     _before_waiting_observer: MainRunLoopObserver,
     _after_waiting_observer: MainRunLoopObserver,
 }
@@ -203,6 +205,7 @@ impl EventLoop {
             // `applicationDidFinishLaunching:`
             unsafe { NSApplicationDidFinishLaunchingNotification },
             move |notification| {
+                let _entered = debug_span!("NSApplicationDidFinishLaunchingNotification").entered();
                 if let Some(app_state) = weak_app_state.upgrade() {
                     app_state.did_finish_launching(notification);
                 }
@@ -215,6 +218,7 @@ impl EventLoop {
             // `applicationWillTerminate:`
             unsafe { NSApplicationWillTerminateNotification },
             move |notification| {
+                let _entered = debug_span!("NSApplicationWillTerminateNotification").entered();
                 if let Some(app_state) = weak_app_state.upgrade() {
                     app_state.will_terminate(notification);
                 }
@@ -224,14 +228,20 @@ impl EventLoop {
         let main_loop = MainRunLoop::get(mtm);
         let mode = unsafe { kCFRunLoopCommonModes }.unwrap();
 
+        // Tracing observers have the lowest and highest orderings.
+        let _tracing_observers = tracing_observers(mtm).inspect(|(start, end)| {
+            main_loop.add_observer(start, mode);
+            main_loop.add_observer(end, mode);
+        });
+
         let app_state_clone = Rc::clone(&app_state);
         let _before_waiting_observer = MainRunLoopObserver::new(
             mtm,
             CFRunLoopActivity::BeforeWaiting,
             true,
-            // Queued with the lowest priority to ensure it is processed after other observers.
-            // Without that, we'd get a `LoopExiting` after `AboutToWait`.
-            CFIndex::MAX,
+            // Queued with the second-lowest priority (tracing observers use the lowest) to ensure
+            // it is processed after other observers.
+            CFIndex::MAX - 1,
             move |_| app_state_clone.cleared(),
         );
         main_loop.add_observer(&_before_waiting_observer, mode);
@@ -241,8 +251,9 @@ impl EventLoop {
             mtm,
             CFRunLoopActivity::AfterWaiting,
             true,
-            // Queued with the highest priority to ensure it is processed before other observers.
-            CFIndex::MIN,
+            // Queued with the second-highest priority (tracing observers use the highest) to
+            // ensure it is processed before other observers.
+            CFIndex::MIN + 1,
             move |_| app_state_clone.wakeup(),
         );
         main_loop.add_observer(&_after_waiting_observer, mode);
@@ -253,6 +264,7 @@ impl EventLoop {
             window_target: ActiveEventLoop { app_state, mtm },
             _did_finish_launching_observer,
             _will_terminate_observer,
+            _tracing_observers,
             _before_waiting_observer,
             _after_waiting_observer,
         })

winit-appkit/src/lib.rs

@@ -76,7 +76,6 @@ mod event_loop;
 mod ffi;
 mod menu;
 mod monitor;
-mod notification_center;
 mod observer;
 mod view;
 mod window;

winit-appkit/src/util.rs

@@ -1,37 +1,10 @@
 use objc2_core_graphics::CGError;
-use tracing::trace;
 use winit_core::error::OsError;
 
 macro_rules! os_error {
     ($error:expr) => {{ winit_core::error::OsError::new(line!(), file!(), $error) }};
 }
 
-macro_rules! trace_scope {
-    ($s:literal) => {
-        let _crate = $crate::util::TraceGuard::new(module_path!(), $s);
-    };
-}
-
-pub(crate) struct TraceGuard {
-    module_path: &'static str,
-    called_from_fn: &'static str,
-}
-
-impl TraceGuard {
-    #[inline]
-    pub(crate) fn new(module_path: &'static str, called_from_fn: &'static str) -> Self {
-        trace!(target = module_path, "Triggered `{}`", called_from_fn);
-        Self { module_path, called_from_fn }
-    }
-}
-
-impl Drop for TraceGuard {
-    #[inline]
-    fn drop(&mut self) {
-        trace!(target = self.module_path, "Completed `{}`", self.called_from_fn);
-    }
-}
-
 #[track_caller]
 pub(crate) fn cgerr(err: CGError) -> Result<(), OsError> {
     if err == CGError::Success { Ok(()) } else { Err(os_error!(format!("CGError {err:?}"))) }

winit-appkit/src/view.rs

@@ -2,12 +2,11 @@
 use std::cell::{Cell, RefCell};
 use std::collections::{HashMap, VecDeque};
 use std::rc::Rc;
-use std::time::Instant;
 
 use dpi::{LogicalPosition, LogicalSize};
 use objc2::rc::Retained;
 use objc2::runtime::{AnyObject, Sel};
-use objc2::{AnyThread, DefinedClass, MainThreadMarker, MainThreadOnly, define_class, msg_send};
+use objc2::{AnyThread, DefinedClass, MainThreadMarker, define_class, msg_send};
 use objc2_app_kit::{
     NSApplication, NSCursor, NSEvent, NSEventPhase, NSResponder, NSTextInputClient, NSTrackingArea,
     NSTrackingAreaOptions, NSView, NSWindow,
@@ -17,7 +16,7 @@ use objc2_foundation::{
     NSArray, NSAttributedString, NSAttributedStringKey, NSCopying, NSMutableAttributedString,
     NSNotFound, NSObject, NSPoint, NSRange, NSRect, NSSize, NSString, NSUInteger,
 };
-use tracing::warn;
+use tracing::{debug_span, trace_span};
 use winit_core::event::{
     DeviceEvent, ElementState, Ime, KeyEvent, Modifiers, MouseButton, MouseScrollDelta,
     PointerKind, PointerSource, TouchPhase, WindowEvent,
@@ -155,7 +154,7 @@ define_class!(
         // Not a normal method on `NSView`, it's triggered by `NSViewFrameDidChangeNotification`.
         #[unsafe(method(viewFrameDidChangeNotification:))]
         fn frame_did_change(&self, _notification: Option<&AnyObject>) {
-            trace_scope!("NSViewFrameDidChangeNotification");
+            let _entered = debug_span!("NSViewFrameDidChangeNotification").entered();
 
             // Emit resize event here rather than from windowDidResize because:
             // 1. When a new window is created as a tab, the frame size may change without a window
@@ -170,7 +169,7 @@ define_class!(
 
         #[unsafe(method(drawRect:))]
         fn draw_rect(&self, _rect: NSRect) {
-            trace_scope!("drawRect:");
+            let _entered = debug_span!("drawRect:").entered();
 
             self.ivars().app_state.handle_redraw(window_id(&self.window()));
 
@@ -179,7 +178,7 @@ define_class!(
 
         #[unsafe(method(acceptsFirstResponder))]
         fn accepts_first_responder(&self) -> bool {
-            trace_scope!("acceptsFirstResponder");
+            let _entered = trace_span!("acceptsFirstResponder").entered();
             true
         }
 
@@ -193,13 +192,13 @@ define_class!(
         // extension for using `NSTouchBar`
         #[unsafe(method_id(touchBar))]
         fn touch_bar(&self) -> Option<Retained<NSObject>> {
-            trace_scope!("touchBar");
+            let _entered = debug_span!("touchBar").entered();
             None
         }
 
         #[unsafe(method(resetCursorRects))]
         fn reset_cursor_rects(&self) {
-            trace_scope!("resetCursorRects");
+            let _entered = debug_span!("resetCursorRects").entered();
             let bounds = self.bounds();
             let cursor_state = self.ivars().cursor_state.borrow();
             // We correctly invoke `addCursorRect` only from inside `resetCursorRects`
@@ -214,13 +213,13 @@ define_class!(
     unsafe impl NSTextInputClient for WinitView {
         #[unsafe(method(hasMarkedText))]
         fn has_marked_text(&self) -> bool {
-            trace_scope!("hasMarkedText");
+            let _entered = debug_span!("hasMarkedText").entered();
             self.ivars().marked_text.borrow().length() > 0
         }
 
         #[unsafe(method(markedRange))]
         fn marked_range(&self) -> NSRange {
-            trace_scope!("markedRange");
+            let _entered = debug_span!("markedRange").entered();
             let length = self.ivars().marked_text.borrow().length();
             if length > 0 {
                 NSRange::new(0, length)
@@ -232,7 +231,7 @@ define_class!(
 
         #[unsafe(method(selectedRange))]
         fn selected_range(&self) -> NSRange {
-            trace_scope!("selectedRange");
+            let _entered = debug_span!("selectedRange").entered();
             // Documented to return `{NSNotFound, 0}` if there is no selection.
             NSRange::new(NSNotFound as NSUInteger, 0)
         }
@@ -245,7 +244,7 @@ define_class!(
             _replacement_range: NSRange,
         ) {
             // TODO: Use _replacement_range, requires changing the event to report surrounding text.
-            trace_scope!("setMarkedText:selectedRange:replacementRange:");
+            let _entered = debug_span!("setMarkedText:selectedRange:replacementRange:").entered();
 
             let (marked_text, string) = if let Some(string) =
                 string.downcast_ref::<NSAttributedString>()
@@ -299,7 +298,7 @@ define_class!(
 
         #[unsafe(method(unmarkText))]
         fn unmark_text(&self) {
-            trace_scope!("unmarkText");
+            let _entered = debug_span!("unmarkText").entered();
             *self.ivars().marked_text.borrow_mut() = NSMutableAttributedString::new();
 
             let input_context = self.inputContext().expect("input context");
@@ -316,7 +315,7 @@ define_class!(
 
         #[unsafe(method_id(validAttributesForMarkedText))]
         fn valid_attributes_for_marked_text(&self) -> Retained<NSArray<NSAttributedStringKey>> {
-            trace_scope!("validAttributesForMarkedText");
+            let _entered = trace_span!("validAttributesForMarkedText").entered();
             NSArray::new()
         }
 
@@ -326,13 +325,14 @@ define_class!(
             _range: NSRange,
             _actual_range: *mut NSRange,
         ) -> Option<Retained<NSAttributedString>> {
-            trace_scope!("attributedSubstringForProposedRange:actualRange:");
+            let _entered =
+                trace_span!("attributedSubstringForProposedRange:actualRange:").entered();
             None
         }
 
         #[unsafe(method(characterIndexForPoint:))]
         fn character_index_for_point(&self, _point: NSPoint) -> NSUInteger {
-            trace_scope!("characterIndexForPoint:");
+            let _entered = debug_span!("characterIndexForPoint:").entered();
             0
         }
 
@@ -342,7 +342,7 @@ define_class!(
             _range: NSRange,
             _actual_range: *mut NSRange,
         ) -> NSRect {
-            trace_scope!("firstRectForCharacterRange:actualRange:");
+            let _entered = debug_span!("firstRectForCharacterRange:actualRange:").entered();
 
             // Guard when the view is no longer in a window during teardown.
             let Some(window) = (**self).window() else {
@@ -358,7 +358,7 @@ define_class!(
         #[unsafe(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:");
+            let _entered = debug_span!("insertText:replacementRange:").entered();
 
             let string = if let Some(string) = string.downcast_ref::<NSAttributedString>() {
                 string.string().to_string()
@@ -383,7 +383,7 @@ define_class!(
         // "human readable" character happens, i.e. newlines, tabs, and Ctrl+C.
         #[unsafe(method(doCommandBySelector:))]
         fn do_command_by_selector(&self, command: Sel) {
-            trace_scope!("doCommandBySelector:");
+            let _entered = debug_span!("doCommandBySelector:").entered();
 
             // We shouldn't forward any character from just committed text, since we'll end up
             // sending it twice with some IMEs like Korean one. We'll also always send
@@ -422,7 +422,7 @@ define_class!(
     impl WinitView {
         #[unsafe(method(keyDown:))]
         fn key_down(&self, event: &NSEvent) {
-            trace_scope!("keyDown:");
+            let _entered = debug_span!("keyDown:").entered();
             {
                 let mut prev_input_source = self.ivars().input_source.borrow_mut();
                 let current_input_source = self.current_input_source();
@@ -481,7 +481,7 @@ define_class!(
 
         #[unsafe(method(keyUp:))]
         fn key_up(&self, event: &NSEvent) {
-            trace_scope!("keyUp:");
+            let _entered = debug_span!("keyUp:").entered();
 
             let event = replace_event(event, self.option_as_alt());
             self.update_modifiers(&event, false);
@@ -498,14 +498,14 @@ define_class!(
 
         #[unsafe(method(flagsChanged:))]
         fn flags_changed(&self, event: &NSEvent) {
-            trace_scope!("flagsChanged:");
+            let _entered = debug_span!("flagsChanged:").entered();
 
             self.update_modifiers(event, true);
         }
 
         #[unsafe(method(insertTab:))]
         fn insert_tab(&self, _sender: Option<&AnyObject>) {
-            trace_scope!("insertTab:");
+            let _entered = debug_span!("insertTab:").entered();
             let window = self.window();
             if let Some(first_responder) = window.firstResponder() {
                 if *first_responder == ***self {
@@ -516,7 +516,7 @@ define_class!(
 
         #[unsafe(method(insertBackTab:))]
         fn insert_back_tab(&self, _sender: Option<&AnyObject>) {
-            trace_scope!("insertBackTab:");
+            let _entered = debug_span!("insertBackTab:").entered();
             let window = self.window();
             if let Some(first_responder) = window.firstResponder() {
                 if *first_responder == ***self {
@@ -530,7 +530,7 @@ define_class!(
         #[unsafe(method(cancelOperation:))]
         fn cancel_operation(&self, _sender: Option<&AnyObject>) {
             let mtm = MainThreadMarker::from(self);
-            trace_scope!("cancelOperation:");
+            let _entered = debug_span!("cancelOperation:").entered();
 
             let event = NSApplication::sharedApplication(mtm)
                 .currentEvent()
@@ -559,71 +559,73 @@ define_class!(
 
         #[unsafe(method(mouseDown:))]
         fn mouse_down(&self, event: &NSEvent) {
-            trace_scope!("mouseDown:");
+            let _entered = debug_span!("mouseDown:").entered();
             self.mouse_motion(event);
             self.mouse_click(event, ElementState::Pressed);
         }
 
         #[unsafe(method(mouseUp:))]
         fn mouse_up(&self, event: &NSEvent) {
-            trace_scope!("mouseUp:");
+            let _entered = debug_span!("mouseUp:").entered();
             self.mouse_motion(event);
             self.mouse_click(event, ElementState::Released);
         }
 
         #[unsafe(method(rightMouseDown:))]
         fn right_mouse_down(&self, event: &NSEvent) {
-            trace_scope!("rightMouseDown:");
+            let _entered = debug_span!("rightMouseDown:").entered();
             self.mouse_motion(event);
             self.mouse_click(event, ElementState::Pressed);
         }
 
         #[unsafe(method(rightMouseUp:))]
         fn right_mouse_up(&self, event: &NSEvent) {
-            trace_scope!("rightMouseUp:");
+            let _entered = debug_span!("rightMouseUp:").entered();
             self.mouse_motion(event);
             self.mouse_click(event, ElementState::Released);
         }
 
         #[unsafe(method(otherMouseDown:))]
         fn other_mouse_down(&self, event: &NSEvent) {
-            trace_scope!("otherMouseDown:");
+            let _entered = debug_span!("otherMouseDown:").entered();
             self.mouse_motion(event);
             self.mouse_click(event, ElementState::Pressed);
         }
 
         #[unsafe(method(otherMouseUp:))]
         fn other_mouse_up(&self, event: &NSEvent) {
-            trace_scope!("otherMouseUp:");
+            let _entered = debug_span!("otherMouseUp:").entered();
             self.mouse_motion(event);
             self.mouse_click(event, ElementState::Released);
         }
 
-        // No tracing on these because that would be overly verbose
-
         #[unsafe(method(mouseMoved:))]
         fn mouse_moved(&self, event: &NSEvent) {
+            let _entered = debug_span!("mouseMoved:").entered();
             self.mouse_motion(event);
         }
 
         #[unsafe(method(mouseDragged:))]
         fn mouse_dragged(&self, event: &NSEvent) {
+            let _entered = debug_span!("mouseDragged:").entered();
             self.mouse_motion(event);
         }
 
         #[unsafe(method(rightMouseDragged:))]
         fn right_mouse_dragged(&self, event: &NSEvent) {
+            let _entered = debug_span!("rightMouseDragged:").entered();
             self.mouse_motion(event);
         }
 
         #[unsafe(method(otherMouseDragged:))]
         fn other_mouse_dragged(&self, event: &NSEvent) {
+            let _entered = debug_span!("otherMouseDragged:").entered();
             self.mouse_motion(event);
         }
 
         #[unsafe(method(mouseEntered:))]
         fn mouse_entered(&self, event: &NSEvent) {
-            trace_scope!("mouseEntered:");
+            let _entered = debug_span!("mouseEntered:").entered();
 
             let position = self.mouse_view_point(event).to_physical(self.scale_factor());
 
@@ -637,7 +639,7 @@ define_class!(
 
         #[unsafe(method(mouseExited:))]
         fn mouse_exited(&self, event: &NSEvent) {
-            trace_scope!("mouseExited:");
+            let _entered = debug_span!("mouseExited:").entered();
 
             let position = self.mouse_view_point(event).to_physical(self.scale_factor());
 
@@ -651,7 +653,7 @@ define_class!(
 
         #[unsafe(method(scrollWheel:))]
         fn scroll_wheel(&self, event: &NSEvent) {
-            trace_scope!("scrollWheel:");
+            let _entered = debug_span!("scrollWheel:").entered();
 
             self.mouse_motion(event);
 
@@ -682,16 +684,15 @@ define_class!(
 
             self.update_modifiers(event, false);
 
-            let time = self.ivars().app_state.event_time(event);
             self.ivars().app_state.maybe_queue_with_handler(move |app, event_loop| {
-                app.device_event(event_loop, None, time, DeviceEvent::MouseWheel { delta })
+                app.device_event(event_loop, None, DeviceEvent::MouseWheel { delta })
             });
             self.queue_event(WindowEvent::MouseWheel { device_id: None, delta, phase });
         }
 
         #[unsafe(method(magnifyWithEvent:))]
         fn magnify_with_event(&self, event: &NSEvent) {
-            trace_scope!("magnifyWithEvent:");
+            let _entered = debug_span!("magnifyWithEvent:").entered();
 
             self.mouse_motion(event);
 
@@ -713,7 +714,7 @@ define_class!(
 
         #[unsafe(method(smartMagnifyWithEvent:))]
         fn smart_magnify_with_event(&self, event: &NSEvent) {
-            trace_scope!("smartMagnifyWithEvent:");
+            let _entered = debug_span!("smartMagnifyWithEvent:").entered();
 
             self.mouse_motion(event);
 
@@ -722,7 +723,7 @@ define_class!(
 
         #[unsafe(method(rotateWithEvent:))]
         fn rotate_with_event(&self, event: &NSEvent) {
-            trace_scope!("rotateWithEvent:");
+            let _entered = debug_span!("rotateWithEvent:").entered();
 
             self.mouse_motion(event);
 
@@ -744,7 +745,7 @@ define_class!(
 
         #[unsafe(method(pressureChangeWithEvent:))]
         fn pressure_change_with_event(&self, event: &NSEvent) {
-            trace_scope!("pressureChangeWithEvent:");
+            let _entered = debug_span!("pressureChangeWithEvent:").entered();
 
             self.queue_event(WindowEvent::TouchpadPressure {
                 device_id: None,
@@ -758,13 +759,13 @@ define_class!(
         // https://github.com/chromium/chromium/blob/a86a8a6bcfa438fa3ac2eba6f02b3ad1f8e0756f/ui/views/cocoa/bridged_content_view.mm#L816
         #[unsafe(method(_wantsKeyDownForEvent:))]
         fn wants_key_down_for_event(&self, _event: &NSEvent) -> bool {
-            trace_scope!("_wantsKeyDownForEvent:");
+            let _entered = debug_span!("_wantsKeyDownForEvent:").entered();
             true
         }
 
         #[unsafe(method(acceptsFirstMouse:))]
         fn accepts_first_mouse(&self, _event: &NSEvent) -> bool {
-            trace_scope!("acceptsFirstMouse:");
+            let _entered = debug_span!("acceptsFirstMouse:").entered();
             self.ivars().accepts_first_mouse
         }
     }
@@ -847,16 +848,9 @@ impl WinitView {
     }
 
     fn queue_event(&self, event: WindowEvent) {
-        let app = NSApplication::sharedApplication(self.mtm());
         let window_id = window_id(&self.window());
-        let time = if let Some(nsevent) = app.currentEvent() {
-            self.ivars().app_state.event_time(&nsevent)
-        } else {
-            warn!("queued event with wrong timestamp, no active NSEvent found");
-            Instant::now()
-        };
         self.ivars().app_state.maybe_queue_with_handler(move |app, event_loop| {
-            app.window_event(event_loop, window_id, time, event);
+            app.window_event(event_loop, window_id, event);
         });
     }
 

winit-appkit/src/window.rs

@@ -8,6 +8,7 @@ use objc2::rc::{Retained, autoreleasepool};
 use objc2::{MainThreadMarker, Message, define_class};
 use objc2_app_kit::{NSPanel, NSResponder, NSWindow};
 use objc2_foundation::NSObject;
+use tracing::trace_span;
 use winit_core::cursor::Cursor;
 use winit_core::error::RequestError;
 use winit_core::icon::Icon;
@@ -350,13 +351,13 @@ define_class!(
     impl WinitWindow {
         #[unsafe(method(canBecomeMainWindow))]
         fn can_become_main_window(&self) -> bool {
-            trace_scope!("canBecomeMainWindow");
+            let _entered = trace_span!("canBecomeMainWindow").entered();
             true
         }
 
         #[unsafe(method(canBecomeKeyWindow))]
         fn can_become_key_window(&self) -> bool {
-            trace_scope!("canBecomeKeyWindow");
+            let _entered = trace_span!("canBecomeKeyWindow").entered();
             true
         }
     }
@@ -374,7 +375,7 @@ define_class!(
         // it doesn't if window doesn't have NSWindowStyleMask::Titled
         #[unsafe(method(canBecomeKeyWindow))]
         fn can_become_key_window(&self) -> bool {
-            trace_scope!("canBecomeKeyWindow");
+            let _entered = trace_span!("canBecomeKeyWindow").entered();
             true
         }
     }

winit-appkit/src/window_delegate.rs

@@ -5,7 +5,6 @@ use std::ffi::c_void;
 use std::ptr;
 use std::rc::Rc;
 use std::sync::{Arc, Mutex};
-use std::time::Instant;
 
 use dpi::{
     LogicalInsets, LogicalPosition, LogicalSize, PhysicalInsets, PhysicalPosition, PhysicalSize,
@@ -42,7 +41,7 @@ use objc2_foundation::{
     NSObjectNSDelayedPerforming, NSObjectNSKeyValueObserverRegistration, NSObjectProtocol, NSPoint,
     NSRect, NSSize, NSString, ns_string,
 };
-use tracing::{trace, warn};
+use tracing::{debug_span, trace, warn};
 use winit_common::core_foundation::MainRunLoop;
 use winit_core::cursor::Cursor;
 use winit_core::error::{NotSupportedError, RequestError};
@@ -122,14 +121,14 @@ define_class!(
     unsafe impl NSWindowDelegate for WindowDelegate {
         #[unsafe(method(windowShouldClose:))]
         fn window_should_close(&self, _: Option<&AnyObject>) -> bool {
-            trace_scope!("windowShouldClose:");
+            let _entered = debug_span!("windowShouldClose:").entered();
             self.queue_event(WindowEvent::CloseRequested);
             false
         }
 
         #[unsafe(method(windowWillClose:))]
         fn window_will_close(&self, _: Option<&AnyObject>) {
-            trace_scope!("windowWillClose:");
+            let _entered = debug_span!("windowWillClose:").entered();
             // `setDelegate:` retains the previous value and then autoreleases it
             autoreleasepool(|_| {
                 // Since El Capitan, we need to be careful that delegate methods can't
@@ -141,14 +140,14 @@ define_class!(
 
         #[unsafe(method(windowDidResize:))]
         fn window_did_resize(&self, _: Option<&AnyObject>) {
-            trace_scope!("windowDidResize:");
+            let _entered = debug_span!("windowDidResize:").entered();
             // NOTE: WindowEvent::SurfaceResized is reported using NSViewFrameDidChangeNotification.
             self.emit_move_event();
         }
 
         #[unsafe(method(windowWillStartLiveResize:))]
         fn window_will_start_live_resize(&self, _: Option<&AnyObject>) {
-            trace_scope!("windowWillStartLiveResize:");
+            let _entered = debug_span!("windowWillStartLiveResize:").entered();
 
             let increments = self.ivars().surface_resize_increments.get();
             self.set_resize_increments_inner(increments);
@@ -156,20 +155,20 @@ define_class!(
 
         #[unsafe(method(windowDidEndLiveResize:))]
         fn window_did_end_live_resize(&self, _: Option<&AnyObject>) {
-            trace_scope!("windowDidEndLiveResize:");
+            let _entered = debug_span!("windowDidEndLiveResize:").entered();
             self.set_resize_increments_inner(NSSize::new(1., 1.));
         }
 
         // This won't be triggered if the move was part of a resize.
         #[unsafe(method(windowDidMove:))]
         fn window_did_move(&self, _: Option<&AnyObject>) {
-            trace_scope!("windowDidMove:");
+            let _entered = debug_span!("windowDidMove:").entered();
             self.emit_move_event();
         }
 
         #[unsafe(method(windowDidChangeBackingProperties:))]
         fn window_did_change_backing_properties(&self, _: Option<&AnyObject>) {
-            trace_scope!("windowDidChangeBackingProperties:");
+            let _entered = debug_span!("windowDidChangeBackingProperties:").entered();
             let scale_factor = self.scale_factor();
             if scale_factor == self.ivars().previous_scale_factor.get() {
                 return;
@@ -185,7 +184,7 @@ define_class!(
 
         #[unsafe(method(windowDidBecomeKey:))]
         fn window_did_become_key(&self, _: Option<&AnyObject>) {
-            trace_scope!("windowDidBecomeKey:");
+            let _entered = debug_span!("windowDidBecomeKey:").entered();
             // TODO: center the cursor if the window had mouse grab when it
             // lost focus
             self.queue_event(WindowEvent::Focused(true));
@@ -193,7 +192,7 @@ define_class!(
 
         #[unsafe(method(windowDidResignKey:))]
         fn window_did_resign_key(&self, _: Option<&AnyObject>) {
-            trace_scope!("windowDidResignKey:");
+            let _entered = debug_span!("windowDidResignKey:").entered();
             // It happens rather often, e.g. when the user is Cmd+Tabbing, that the
             // NSWindowDelegate will receive a didResignKey event despite no event
             // being received when the modifiers are released. This is because
@@ -209,7 +208,7 @@ define_class!(
         /// Invoked when before enter fullscreen
         #[unsafe(method(windowWillEnterFullScreen:))]
         fn window_will_enter_fullscreen(&self, _: Option<&AnyObject>) {
-            trace_scope!("windowWillEnterFullScreen:");
+            let _entered = debug_span!("windowWillEnterFullScreen:").entered();
 
             self.ivars().maximized.set(self.is_zoomed());
             let mut fullscreen = self.ivars().fullscreen.borrow_mut();
@@ -237,7 +236,7 @@ define_class!(
         /// Invoked when before exit fullscreen
         #[unsafe(method(windowWillExitFullScreen:))]
         fn window_will_exit_fullscreen(&self, _: Option<&AnyObject>) {
-            trace_scope!("windowWillExitFullScreen:");
+            let _entered = debug_span!("windowWillExitFullScreen:").entered();
 
             self.ivars().in_fullscreen_transition.set(true);
         }
@@ -248,7 +247,7 @@ define_class!(
             _: Option<&AnyObject>,
             proposed_options: NSApplicationPresentationOptions,
         ) -> NSApplicationPresentationOptions {
-            trace_scope!("window:willUseFullScreenPresentationOptions:");
+            let _entered = debug_span!("window:willUseFullScreenPresentationOptions:").entered();
             // Generally, games will want to disable the menu bar and the dock. Ideally,
             // this would be configurable by the user. Unfortunately because of our
             // `CGShieldingWindowLevel() + 1` hack (see `set_fullscreen`), our window is
@@ -271,7 +270,7 @@ define_class!(
         /// Invoked when entered fullscreen
         #[unsafe(method(windowDidEnterFullScreen:))]
         fn window_did_enter_fullscreen(&self, _: Option<&AnyObject>) {
-            trace_scope!("windowDidEnterFullScreen:");
+            let _entered = debug_span!("windowDidEnterFullScreen:").entered();
             self.ivars().initial_fullscreen.set(false);
             self.ivars().in_fullscreen_transition.set(false);
             if let Some(target_fullscreen) = self.ivars().target_fullscreen.take() {
@@ -282,7 +281,7 @@ define_class!(
         /// Invoked when exited fullscreen
         #[unsafe(method(windowDidExitFullScreen:))]
         fn window_did_exit_fullscreen(&self, _: Option<&AnyObject>) {
-            trace_scope!("windowDidExitFullScreen:");
+            let _entered = debug_span!("windowDidExitFullScreen:").entered();
 
             self.restore_state_from_fullscreen();
             self.ivars().in_fullscreen_transition.set(false);
@@ -309,7 +308,7 @@ define_class!(
         /// work you may have done to prepare to enter full-screen mode.
         #[unsafe(method(windowDidFailToEnterFullScreen:))]
         fn window_did_fail_to_enter_fullscreen(&self, _: Option<&AnyObject>) {
-            trace_scope!("windowDidFailToEnterFullScreen:");
+            let _entered = debug_span!("windowDidFailToEnterFullScreen:").entered();
             self.ivars().in_fullscreen_transition.set(false);
             self.ivars().target_fullscreen.replace(None);
             if self.ivars().initial_fullscreen.get() {
@@ -328,7 +327,7 @@ define_class!(
         // Invoked when the occlusion state of the window changes
         #[unsafe(method(windowDidChangeOcclusionState:))]
         fn window_did_change_occlusion_state(&self, _: Option<&AnyObject>) {
-            trace_scope!("windowDidChangeOcclusionState:");
+            let _entered = debug_span!("windowDidChangeOcclusionState:").entered();
             let visible = self.window().occlusionState().contains(NSWindowOcclusionState::Visible);
             self.queue_event(WindowEvent::Occluded(!visible));
 
@@ -349,7 +348,7 @@ define_class!(
 
         #[unsafe(method(windowDidChangeScreen:))]
         fn window_did_change_screen(&self, _: Option<&AnyObject>) {
-            trace_scope!("windowDidChangeScreen:");
+            let _entered = debug_span!("windowDidChangeScreen:").entered();
             let is_simple_fullscreen = self.ivars().is_simple_fullscreen.get();
             if is_simple_fullscreen {
                 if let Some(screen) = self.window().screen() {
@@ -363,7 +362,7 @@ define_class!(
         /// Invoked when the dragged image enters destination bounds or frame
         #[unsafe(method(draggingEntered:))]
         fn dragging_entered(&self, sender: &ProtocolObject<dyn NSDraggingInfo>) -> bool {
-            trace_scope!("draggingEntered:");
+            let _entered = debug_span!("draggingEntered:").entered();
 
             use std::path::PathBuf;
 
@@ -394,7 +393,7 @@ define_class!(
 
         #[unsafe(method(wantsPeriodicDraggingUpdates))]
         fn wants_periodic_dragging_updates(&self) -> bool {
-            trace_scope!("wantsPeriodicDraggingUpdates:");
+            let _entered = debug_span!("wantsPeriodicDraggingUpdates:").entered();
             true
         }
 
@@ -402,7 +401,7 @@ define_class!(
         /// modification of the dragging operation or mouse-pointer position.
         #[unsafe(method(draggingUpdated:))]
         fn dragging_updated(&self, sender: &ProtocolObject<dyn NSDraggingInfo>) -> bool {
-            trace_scope!("draggingUpdated:");
+            let _entered = debug_span!("draggingUpdated:").entered();
 
             let dl = sender.draggingLocation();
             let dl = self.view().convertPoint_fromView(dl, None);
@@ -417,14 +416,14 @@ define_class!(
         /// Invoked when the image is released
         #[unsafe(method(prepareForDragOperation:))]
         fn prepare_for_drag_operation(&self, _sender: &NSObject) -> bool {
-            trace_scope!("prepareForDragOperation:");
+            let _entered = debug_span!("prepareForDragOperation:").entered();
             true
         }
 
         /// Invoked after the released image has been removed from the screen
         #[unsafe(method(performDragOperation:))]
         fn perform_drag_operation(&self, sender: &ProtocolObject<dyn NSDraggingInfo>) -> bool {
-            trace_scope!("performDragOperation:");
+            let _entered = debug_span!("performDragOperation:").entered();
 
             use std::path::PathBuf;
 
@@ -456,13 +455,13 @@ define_class!(
         /// Invoked when the dragging operation is complete
         #[unsafe(method(concludeDragOperation:))]
         fn conclude_drag_operation(&self, _sender: Option<&NSObject>) {
-            trace_scope!("concludeDragOperation:");
+            let _entered = debug_span!("concludeDragOperation:").entered();
         }
 
         /// Invoked when the dragging operation is cancelled
         #[unsafe(method(draggingExited:))]
         fn dragging_exited(&self, sender: Option<&ProtocolObject<dyn NSDraggingInfo>>) {
-            trace_scope!("draggingExited:");
+            let _entered = debug_span!("draggingExited:").entered();
 
             let position = sender.map(|sender| {
                 let dl = sender.draggingLocation();
@@ -484,7 +483,7 @@ define_class!(
             change: Option<&NSDictionary<NSKeyValueChangeKey, AnyObject>>,
             _context: *mut c_void,
         ) {
-            trace_scope!("observeValueForKeyPath:ofObject:change:context:");
+            let _entered = debug_span!("observeValueForKeyPath:ofObject:change:context:").entered();
             // 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")) {
@@ -904,16 +903,9 @@ impl WindowDelegate {
     }
 
     pub(crate) fn queue_event(&self, event: WindowEvent) {
-        let app = NSApplication::sharedApplication(self.mtm());
         let window_id = window_id(self.window());
-        let time = if let Some(nsevent) = app.currentEvent() {
-            self.ivars().app_state.event_time(&nsevent)
-        } else {
-            warn!("queued event with wrong timestamp, no active NSEvent found");
-            Instant::now()
-        };
         self.ivars().app_state.maybe_queue_with_handler(move |app, event_loop| {
-            app.window_event(event_loop, window_id, time, event);
+            app.window_event(event_loop, window_id, event);
         });
     }
 

winit-common/Cargo.toml

@@ -20,6 +20,9 @@ xkb = ["dep:xkbcommon-dl", "dep:smol_str"]
 # CoreFoundation
 core-foundation = ["dep:block2", "dep:objc2", "dep:objc2-core-foundation"]
 
+# Foundation
+foundation = ["dep:block2", "dep:objc2", "dep:objc2-foundation"]
+
 [dependencies]
 smol_str = { workspace = true, optional = true }
 tracing.workspace = true
@@ -30,7 +33,7 @@ memmap2 = { workspace = true, optional = true }
 x11-dl = { workspace = true, optional = true }
 xkbcommon-dl = { workspace = true, optional = true }
 
-# CoreFoundation
+# Foundation / CoreFoundation
 block2 = { workspace = true, optional = true }
 objc2 = { workspace = true, optional = true }
 objc2-core-foundation = { workspace = true, optional = true, features = [
@@ -40,6 +43,13 @@ objc2-core-foundation = { workspace = true, optional = true, features = [
     "CFRunLoop",
     "CFString",
 ] }
+objc2-foundation = { workspace = true, optional = true, features = [
+    "std",
+    "block2",
+    "NSNotification",
+    "NSString",
+    "NSOperation",
+] }
 
 [package.metadata.docs.rs]
 all-features = true

winit-common/src/core_foundation/main_run_loop.rs

@@ -9,7 +9,7 @@ use std::cell::Cell;
 
 use objc2::MainThreadMarker;
 use objc2_core_foundation::{CFRetained, CFRunLoop, CFRunLoopMode, kCFRunLoopDefaultMode};
-use tracing::error;
+use tracing::{Span, error};
 
 use super::MainRunLoopObserver;
 
@@ -49,7 +49,8 @@ impl MainRunLoop {
     /// 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:]`.
+    /// 1. Using `CFRunLoopPerformBlock` or `-[NSRunLoop performBlock:]` to queue a closure to run
+    ///    the next time runloop sources are processed.
     ///
     /// 2. Using `-[NSObject performSelectorOnMainThread:withObject:waitUntilDone:]` or wrapping the
     ///    event in `NSEvent` and posting that to `-[NSApplication postEvent:atStart:]` (both
@@ -73,9 +74,17 @@ impl MainRunLoop {
     /// 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) {
+        // We use this to run a closure asynchronously at a later point, so it also makes sense to
+        // re-enter the current span when running the queued closure.
+        let span = Span::current();
+
         // Convert `FnOnce()` to `Block<dyn Fn()>`.
         let closure = Cell::new(Some(closure));
         let block = block2::RcBlock::new(move || {
+            // Running this block happens inside a `CFRunLoopSource`, but the spans that we emit for
+            // that are (intentionally) overwritten by entering the span from before.
+            let _enter = span.enter();
+
             debug_assert!(MainThreadMarker::new().is_some());
             if let Some(closure) = closure.take() {
                 closure()

winit-common/src/core_foundation/mod.rs

@@ -6,7 +6,9 @@
 mod event_loop_proxy;
 mod main_run_loop;
 mod main_run_loop_observer;
+mod tracing_observers;
 
 pub use self::event_loop_proxy::*;
 pub use self::main_run_loop::*;
 pub use self::main_run_loop_observer::*;
+pub use self::tracing_observers::*;

winit-common/src/core_foundation/tracing_observers.rs

@@ -0,0 +1,146 @@
+use std::cell::RefCell;
+use std::rc::Rc;
+
+use objc2::MainThreadMarker;
+use objc2_core_foundation::{CFIndex, CFRunLoop, CFRunLoopActivity, kCFRunLoopDefaultMode};
+use tracing::span::EnteredSpan;
+use tracing::{Level, error, field, span_enabled, trace_span};
+
+use crate::core_foundation::MainRunLoopObserver;
+
+/// Create two run loop observers that add TRACE-level [spans][tracing::span].
+///
+/// This is useful when debugging run loops, it makes it easier to see in which run loop activity an
+/// event is triggered inside (if any).
+///
+/// When debugging these interactions, it can also be useful to configure your tracing subscriber
+/// with `.with_span_events(tracing_subscriber::fmt::format::FmtSpan::ACTIVE)` to emit events upon
+/// entering and exiting these stages.
+pub fn tracing_observers(
+    mtm: MainThreadMarker,
+) -> Option<(MainRunLoopObserver, MainRunLoopObserver)> {
+    // Observers are a bit costly, so don't create them if the tracing-level for this module is
+    // configured to disable them.
+    if !span_enabled!(Level::TRACE) {
+        return None;
+    }
+
+    /// The state that we think the runloop is currently in.
+    ///
+    /// The order of activities we observe if waiting twice looks something like:
+    /// - CFRunLoopActivity::Entry
+    /// - CFRunLoopActivity::BeforeTimers
+    /// - CFRunLoopActivity::BeforeSources
+    /// - CFRunLoopActivity::BeforeWaiting
+    /// - CFRunLoopActivity::AfterWaiting
+    /// - CFRunLoopActivity::BeforeTimers
+    /// - CFRunLoopActivity::BeforeSources
+    /// - CFRunLoopActivity::BeforeWaiting
+    /// - CFRunLoopActivity::AfterWaiting
+    /// - CFRunLoopActivity::Exit
+    ///
+    /// And if not waiting, it looks something like:
+    /// - CFRunLoopActivity::Entry
+    /// - CFRunLoopActivity::BeforeTimers
+    /// - CFRunLoopActivity::BeforeSources
+    /// - CFRunLoopActivity::Exit
+    #[derive(Default)]
+    #[allow(unused)] // EnteredSpans are kept around
+    enum RunLoopState {
+        /// Currently processing `Entry`/`Exit` observers.
+        #[default]
+        Entered,
+        /// Currently processing timers or `BeforeTimers` observers.
+        Timers(EnteredSpan),
+        /// Currently processing sources or `BeforeSources` observers.
+        Sources(EnteredSpan),
+        /// Currently waiting or processing `BeforeWaiting`/`AfterWaiting` observers.
+        Waiting(EnteredSpan),
+    }
+
+    // A list of currently entered (outer) spans and their state.
+    //
+    // This is a list because runloops can be run recursively.
+    let spans: Rc<RefCell<Vec<(EnteredSpan, RunLoopState)>>> = Rc::new(RefCell::new(Vec::new()));
+    let spans_clone = Rc::clone(&spans);
+
+    // An observer at the start of run loop activities.
+    let activities = CFRunLoopActivity::Entry
+        | CFRunLoopActivity::BeforeTimers
+        | CFRunLoopActivity::BeforeSources
+        | CFRunLoopActivity::BeforeWaiting;
+    let start = MainRunLoopObserver::new(mtm, activities, true, CFIndex::MIN, move |activity| {
+        match activity {
+            // Add an outer span for each runloop iteration.
+            CFRunLoopActivity::Entry => {
+                let span = trace_span!("inside runloop", mode = field::Empty);
+
+                // Get the mode dynamically, the observer may added to multiple different modes.
+                let mode = CFRunLoop::current().unwrap().current_mode().unwrap();
+                // Mode isn't interesting if it's the default mode.
+                if &*mode != unsafe { kCFRunLoopDefaultMode }.unwrap() {
+                    span.record("mode", field::display(mode));
+                }
+
+                let entered = span.entered();
+                spans.borrow_mut().push((entered, RunLoopState::Entered));
+            },
+
+            // Add inner spans that help inspecting the state the runloop is in.
+            CFRunLoopActivity::BeforeTimers => {
+                if let Some((_, state)) = spans.borrow_mut().last_mut() {
+                    *state = RunLoopState::Entered; // Drop any previous spans.
+                    *state = RunLoopState::Timers(trace_span!("processing timers").entered());
+                } else {
+                    error!("unbalanced observer invocations");
+                }
+            },
+            CFRunLoopActivity::BeforeSources => {
+                if let Some((_, state)) = spans.borrow_mut().last_mut() {
+                    *state = RunLoopState::Entered; // Drop any previous spans.
+                    *state = RunLoopState::Sources(trace_span!("processing sources").entered());
+                } else {
+                    error!("unbalanced observer invocations");
+                }
+            },
+            CFRunLoopActivity::BeforeWaiting => {
+                if let Some((_, state)) = spans.borrow_mut().last_mut() {
+                    *state = RunLoopState::Entered; // Drop any previous spans.
+                    *state = RunLoopState::Waiting(trace_span!("waiting").entered());
+                } else {
+                    error!("unbalanced observer invocations");
+                }
+            },
+
+            activity => unreachable!("unexpected activity: {activity:?}"),
+        }
+    });
+
+    // An observer at the end of run loop activities.
+    let activities = CFRunLoopActivity::AfterWaiting | CFRunLoopActivity::Exit;
+    let end = MainRunLoopObserver::new(mtm, activities, true, CFIndex::MAX, move |activity| {
+        match activity {
+            CFRunLoopActivity::AfterWaiting => {
+                if let Some((_, state)) = spans_clone.borrow_mut().last_mut() {
+                    // Transition from the waiting state to the initial state.
+                    *state = RunLoopState::Entered;
+                } else {
+                    error!("unbalanced observer invocations");
+                }
+            },
+
+            CFRunLoopActivity::Exit => {
+                if let Some((span, state)) = spans_clone.borrow_mut().pop() {
+                    drop(state); // Explicitly exit and drop inner span.
+                    drop(span); // Explicitly exit and drop outer span.
+                } else {
+                    error!("unbalanced observer invocations");
+                }
+            },
+
+            activity => unreachable!("unexpected activity: {activity:?}"),
+        }
+    });
+
+    Some((start, end))
+}

winit-common/src/event_handler.rs

@@ -79,6 +79,10 @@ impl EventHandler {
                         // Allowed, happens if the handler was cleared manually
                         // elsewhere (such as in `applicationWillTerminate:`).
                     },
+                    // We use `eprintln!` here over `tracing::error!`, since we're going to abort
+                    // immediately after this, and it'd be annoying for the user if they didn't get
+                    // any feedback on that if they don't have a tracing subscriber.
+                    #[allow(clippy::disallowed_macros)]
                     Err(_) => {
                         // Note: This is not expected to ever happen, this
                         // module generally controls the `RefCell`, and

winit-common/src/foundation/mod.rs

@@ -0,0 +1,3 @@
+mod notification_center;
+
+pub use self::notification_center::*;

winit-common/src/foundation/notification_center.rs

@@ -1,4 +1,3 @@
-// NOTE: This is symlinked to be contained in both the AppKit and UIKit implementations.
 use std::ptr::NonNull;
 
 use block2::RcBlock;
@@ -12,7 +11,7 @@ use objc2_foundation::{
 ///
 /// This is used in Winit as an alternative to declaring an application delegate, as we want to
 /// give the user full control over those.
-pub(crate) fn create_observer(
+pub fn create_observer(
     center: &NSNotificationCenter,
     name: &NSNotificationName,
     handler: impl Fn(&NSNotification) + 'static,

winit-common/src/lib.rs

@@ -4,5 +4,7 @@
 pub mod core_foundation;
 #[cfg(feature = "event-handler")]
 pub mod event_handler;
+#[cfg(feature = "foundation")]
+pub mod foundation;
 #[cfg(feature = "xkb")]
 pub mod xkb;

winit-core/src/application/mod.rs

@@ -1,9 +1,4 @@
 //! End user application handling.
-#[cfg(not(target_family = "wasm"))]
-use std::time::Instant;
-
-#[cfg(target_family = "wasm")]
-use web_time::Instant;
 
 use crate::event::{DeviceEvent, DeviceId, StartCause, WindowEvent};
 use crate::event_loop::ActiveEventLoop;
@@ -197,14 +192,10 @@ pub trait ApplicationHandler {
     }
 
     /// Emitted when the OS sends an event to a winit window.
-    ///
-    /// Contains the ID of the window, the event, and the time the event was received. Note that
-    /// since events are queued, the time will differ from [`Instant::now()`].
     fn window_event(
         &mut self,
         event_loop: &dyn ActiveEventLoop,
         window_id: WindowId,
-        timestamp: Instant,
         event: WindowEvent,
     );
 
@@ -215,10 +206,9 @@ pub trait ApplicationHandler {
         &mut self,
         event_loop: &dyn ActiveEventLoop,
         device_id: Option<DeviceId>,
-        timestamp: Instant,
         event: DeviceEvent,
     ) {
-        let _ = (event_loop, device_id, timestamp, event);
+        let _ = (event_loop, device_id, event);
     }
 
     /// Emitted when the event loop is about to block and wait for new events.
@@ -382,10 +372,9 @@ impl<A: ?Sized + ApplicationHandler> ApplicationHandler for &mut A {
         &mut self,
         event_loop: &dyn ActiveEventLoop,
         window_id: WindowId,
-        timestamp: Instant,
         event: WindowEvent,
     ) {
-        (**self).window_event(event_loop, window_id, timestamp, event);
+        (**self).window_event(event_loop, window_id, event);
     }
 
     #[inline]
@@ -393,10 +382,9 @@ impl<A: ?Sized + ApplicationHandler> ApplicationHandler for &mut A {
         &mut self,
         event_loop: &dyn ActiveEventLoop,
         device_id: Option<DeviceId>,
-        timestamp: Instant,
         event: DeviceEvent,
     ) {
-        (**self).device_event(event_loop, device_id, timestamp, event);
+        (**self).device_event(event_loop, device_id, event);
     }
 
     #[inline]
@@ -452,10 +440,9 @@ impl<A: ?Sized + ApplicationHandler> ApplicationHandler for Box<A> {
         &mut self,
         event_loop: &dyn ActiveEventLoop,
         window_id: WindowId,
-        timestamp: Instant,
         event: WindowEvent,
     ) {
-        (**self).window_event(event_loop, window_id, timestamp, event);
+        (**self).window_event(event_loop, window_id, event);
     }
 
     #[inline]
@@ -463,10 +450,9 @@ impl<A: ?Sized + ApplicationHandler> ApplicationHandler for Box<A> {
         &mut self,
         event_loop: &dyn ActiveEventLoop,
         device_id: Option<DeviceId>,
-        timestamp: Instant,
         event: DeviceEvent,
     ) {
-        (**self).device_event(event_loop, device_id, timestamp, event);
+        (**self).device_event(event_loop, device_id, event);
     }
 
     #[inline]

winit-uikit/Cargo.toml

@@ -69,7 +69,7 @@ objc2-ui-kit = { workspace = true, features = [
     "UIViewController",
     "UIWindow",
 ] }
-winit-common = { workspace = true, features = ["core-foundation", "event-handler"] }
+winit-common = { workspace = true, features = ["core-foundation", "event-handler", "foundation"] }
 
 [package.metadata.docs.rs]
 all-features = true

winit-uikit/src/event_loop.rs

@@ -12,7 +12,9 @@ use objc2_ui_kit::{
     UIApplicationWillResignActiveNotification, UIApplicationWillTerminateNotification, UIScreen,
 };
 use rwh_06::HasDisplayHandle;
-use winit_common::core_foundation::{MainRunLoop, MainRunLoopObserver};
+use tracing::debug_span;
+use winit_common::core_foundation::{MainRunLoop, MainRunLoopObserver, tracing_observers};
+use winit_common::foundation::create_observer;
 use winit_core::application::ApplicationHandler;
 use winit_core::cursor::{CustomCursor, CustomCursorSource};
 use winit_core::error::{EventLoopError, NotSupportedError, RequestError};
@@ -24,7 +26,6 @@ use winit_core::monitor::MonitorHandle as CoreMonitorHandle;
 use winit_core::window::{Theme, Window as CoreWindow};
 
 use super::app_state::{AppState, send_occluded_event_for_all_windows};
-use super::notification_center::create_observer;
 use crate::monitor::MonitorHandle;
 use crate::window::Window;
 use crate::{app_state, monitor};
@@ -134,6 +135,7 @@ pub struct EventLoop {
     _will_terminate_observer: Retained<ProtocolObject<dyn NSObjectProtocol>>,
     _did_receive_memory_warning_observer: Retained<ProtocolObject<dyn NSObjectProtocol>>,
 
+    _tracing_observers: Option<(MainRunLoopObserver, MainRunLoopObserver)>,
     _wakeup_observer: MainRunLoopObserver,
     _main_events_cleared_observer: MainRunLoopObserver,
     _events_cleared_observer: MainRunLoopObserver,
@@ -159,6 +161,7 @@ impl EventLoop {
             // `application:didFinishLaunchingWithOptions:`
             unsafe { UIApplicationDidFinishLaunchingNotification },
             move |_| {
+                let _entered = debug_span!("UIApplicationDidFinishLaunchingNotification").entered();
                 app_state::did_finish_launching(mtm);
             },
         );
@@ -166,19 +169,27 @@ impl EventLoop {
             &center,
             // `applicationDidBecomeActive:`
             unsafe { UIApplicationDidBecomeActiveNotification },
-            move |_| app_state::handle_resumed(mtm),
+            move |_| {
+                let _entered = debug_span!("UIApplicationDidBecomeActiveNotification").entered();
+                app_state::handle_resumed(mtm)
+            },
         );
         let _will_resign_active_observer = create_observer(
             &center,
             // `applicationWillResignActive:`
             unsafe { UIApplicationWillResignActiveNotification },
-            move |_| app_state::handle_suspended(mtm),
+            move |_| {
+                let _entered = debug_span!("UIApplicationWillResignActiveNotification").entered();
+                app_state::handle_suspended(mtm)
+            },
         );
         let _will_enter_foreground_observer = create_observer(
             &center,
             // `applicationWillEnterForeground:`
             unsafe { UIApplicationWillEnterForegroundNotification },
             move |notification| {
+                let _entered =
+                    debug_span!("UIApplicationWillEnterForegroundNotification").entered();
                 let app = notification.object().expect(
                     "UIApplicationWillEnterForegroundNotification to have application object",
                 );
@@ -193,6 +204,7 @@ impl EventLoop {
             // `applicationDidEnterBackground:`
             unsafe { UIApplicationDidEnterBackgroundNotification },
             move |notification| {
+                let _entered = debug_span!("UIApplicationDidEnterBackgroundNotification").entered();
                 let app = notification.object().expect(
                     "UIApplicationDidEnterBackgroundNotification to have application object",
                 );
@@ -207,6 +219,7 @@ impl EventLoop {
             // `applicationWillTerminate:`
             unsafe { UIApplicationWillTerminateNotification },
             move |notification| {
+                let _entered = debug_span!("UIApplicationWillTerminateNotification").entered();
                 let app = notification
                     .object()
                     .expect("UIApplicationWillTerminateNotification to have application object");
@@ -220,18 +233,29 @@ impl EventLoop {
             &center,
             // `applicationDidReceiveMemoryWarning:`
             unsafe { UIApplicationDidReceiveMemoryWarningNotification },
-            move |_| app_state::handle_memory_warning(mtm),
+            move |_| {
+                let _entered =
+                    debug_span!("UIApplicationDidReceiveMemoryWarningNotification").entered();
+                app_state::handle_memory_warning(mtm)
+            },
         );
 
         let main_loop = MainRunLoop::get(mtm);
         let mode = unsafe { kCFRunLoopDefaultMode }.unwrap();
 
+        // Tracing observers have the lowest and highest orderings.
+        let _tracing_observers = tracing_observers(mtm).inspect(|(start, end)| {
+            main_loop.add_observer(start, mode);
+            main_loop.add_observer(end, mode);
+        });
+
         let _wakeup_observer = MainRunLoopObserver::new(
             mtm,
             CFRunLoopActivity::AfterWaiting,
             true,
-            // Queued with the highest priority to ensure it is processed before other observers.
-            CFIndex::MIN,
+            // Queued with the second-highest priority (tracing observers use the highest) to
+            // ensure it is processed before other observers.
+            CFIndex::MIN + 1,
             move |_| app_state::handle_wakeup_transition(mtm),
         );
         main_loop.add_observer(&_wakeup_observer, mode);
@@ -241,17 +265,17 @@ impl EventLoop {
             CFRunLoopActivity::BeforeWaiting,
             true,
             // Core Animation registers its `CFRunLoopObserver` that performs drawing operations in
-            // `CA::Transaction::ensure_implicit` with a priority of `0x1e8480`. We set the
+            // `CA::Transaction::ensure_implicit` with a priority of `2000000`. We set the
             // main_end priority to be 0, in order to send `AboutToWait` before `RedrawRequested`.
             // This value was chosen conservatively to guard against apple using different
             // priorities for their redraw observers in different OS's or on different devices. If
             // it so happens that it's too conservative, the main symptom would be non-redraw
             // events coming in after `AboutToWait`.
             //
-            // The value of `0x1e8480` was determined by inspecting stack traces and the associated
+            // The value of `2000000` was determined by inspecting stack traces and the associated
             // registers for every `CFRunLoopAddObserver` call on an iPad Air 2 running iOS 11.4.
             //
-            // Also tested to be `0x1e8480` on iPhone 8, iOS 13 beta 4.
+            // Also tested to be `2000000` on iPhone 8, iOS 13 beta 4.
             0,
             move |_| app_state::handle_main_events_cleared(mtm),
         );
@@ -261,8 +285,9 @@ impl EventLoop {
             mtm,
             CFRunLoopActivity::BeforeWaiting,
             true,
-            // Queued with the lowest priority to ensure it is processed after other observers.
-            CFIndex::MAX,
+            // Queued with the second-lowest priority (tracing observers use the lowest) to ensure
+            // it is processed after other observers.
+            CFIndex::MAX - 1,
             move |_| app_state::handle_events_cleared(mtm),
         );
         main_loop.add_observer(&_events_cleared_observer, mode);
@@ -277,6 +302,7 @@ impl EventLoop {
             _did_enter_background_observer,
             _will_terminate_observer,
             _did_receive_memory_warning_observer,
+            _tracing_observers,
             _wakeup_observer,
             _main_events_cleared_observer,
             _events_cleared_observer,

winit-uikit/src/lib.rs

@@ -103,7 +103,6 @@
 mod app_state;
 mod event_loop;
 mod monitor;
-mod notification_center;
 mod view;
 mod view_controller;
 mod window;

winit-uikit/src/notification_center.rs

@@ -1 +0,0 @@
-../../winit-appkit/src/notification_center.rs

winit-uikit/src/view.rs

@@ -13,7 +13,7 @@ use objc2_ui_kit::{
     UIResponder, UIRotationGestureRecognizer, UITapGestureRecognizer, UITextInputTraits, UITouch,
     UITouchPhase, UITouchType, UITraitEnvironment, UIView,
 };
-use tracing::debug;
+use tracing::{debug, debug_span, trace_span};
 use winit_core::event::{
     ButtonSource, ElementState, FingerId, Force, KeyEvent, PointerKind, PointerSource,
     TabletToolAngle, TabletToolButton, TabletToolData, TabletToolKind, TouchPhase, WindowEvent,
@@ -48,6 +48,7 @@ define_class!(
     impl WinitView {
         #[unsafe(method(drawRect:))]
         fn draw_rect(&self, rect: CGRect) {
+            let _entered = debug_span!("drawRect:").entered();
             let mtm = MainThreadMarker::new().unwrap();
             let window = self.window().unwrap();
             app_state::handle_nonuser_event(mtm, EventWrapper::Window {
@@ -59,6 +60,7 @@ define_class!(
 
         #[unsafe(method(layoutSubviews))]
         fn layout_subviews(&self) {
+            let _entered = debug_span!("layoutSubviews").entered();
             let mtm = MainThreadMarker::new().unwrap();
             let _: () = unsafe { msg_send![super(self), layoutSubviews] };
 
@@ -79,6 +81,7 @@ define_class!(
 
         #[unsafe(method(setContentScaleFactor:))]
         fn set_content_scale_factor(&self, untrusted_scale_factor: CGFloat) {
+            let _entered = debug_span!("setContentScaleFactor:").entered();
             let mtm = MainThreadMarker::new().unwrap();
             let _: () =
                 unsafe { msg_send![super(self), setContentScaleFactor: untrusted_scale_factor] };
@@ -124,6 +127,7 @@ define_class!(
 
         #[unsafe(method(safeAreaInsetsDidChange))]
         fn safe_area_changed(&self) {
+            let _entered = debug_span!("safeAreaInsetsDidChange").entered();
             debug!("safeAreaInsetsDidChange was called, requesting redraw");
             // When the safe area changes we want to make sure to emit a redraw event
             self.setNeedsDisplay();
@@ -131,26 +135,31 @@ define_class!(
 
         #[unsafe(method(touchesBegan:withEvent:))]
         fn touches_began(&self, touches: &NSSet<UITouch>, _event: Option<&UIEvent>) {
+            let _entered = debug_span!("touchesBegan:withEvent:").entered();
             self.handle_touches(touches)
         }
 
         #[unsafe(method(touchesMoved:withEvent:))]
         fn touches_moved(&self, touches: &NSSet<UITouch>, _event: Option<&UIEvent>) {
+            let _entered = debug_span!("touchesMoved:withEvent:").entered();
             self.handle_touches(touches)
         }
 
         #[unsafe(method(touchesEnded:withEvent:))]
         fn touches_ended(&self, touches: &NSSet<UITouch>, _event: Option<&UIEvent>) {
+            let _entered = debug_span!("touchesEnded:withEvent:").entered();
             self.handle_touches(touches)
         }
 
         #[unsafe(method(touchesCancelled:withEvent:))]
         fn touches_cancelled(&self, touches: &NSSet<UITouch>, _event: Option<&UIEvent>) {
+            let _entered = debug_span!("touchesCancelled:withEvent:").entered();
             self.handle_touches(touches)
         }
 
         #[unsafe(method(pinchGesture:))]
         fn pinch_gesture(&self, recognizer: &UIPinchGestureRecognizer) {
+            let _entered = debug_span!("pinchGesture:").entered();
             let window = self.window().unwrap();
 
             let (phase, delta) = match recognizer.state() {
@@ -185,6 +194,7 @@ define_class!(
 
         #[unsafe(method(doubleTapGesture:))]
         fn double_tap_gesture(&self, recognizer: &UITapGestureRecognizer) {
+            let _entered = debug_span!("doubleTapGesture:").entered();
             let window = self.window().unwrap();
 
             if recognizer.state() == UIGestureRecognizerState::Ended {
@@ -200,6 +210,7 @@ define_class!(
 
         #[unsafe(method(rotationGesture:))]
         fn rotation_gesture(&self, recognizer: &UIRotationGestureRecognizer) {
+            let _entered = debug_span!("rotationGesture:").entered();
             let window = self.window().unwrap();
 
             let (phase, delta) = match recognizer.state() {
@@ -244,6 +255,7 @@ define_class!(
 
         #[unsafe(method(panGesture:))]
         fn pan_gesture(&self, recognizer: &UIPanGestureRecognizer) {
+            let _entered = debug_span!("panGesture:").entered();
             let window = self.window().unwrap();
 
             let translation = recognizer.translationInView(Some(self));
@@ -296,6 +308,7 @@ define_class!(
 
         #[unsafe(method(canBecomeFirstResponder))]
         fn can_become_first_responder(&self) -> bool {
+            let _entered = trace_span!("canBecomeFirstResponder").entered();
             true
         }
     }
@@ -309,6 +322,10 @@ define_class!(
             _gesture_recognizer: &UIGestureRecognizer,
             _other_gesture_recognizer: &UIGestureRecognizer,
         ) -> bool {
+            let _entered = trace_span!(
+                "gestureRecognizer:shouldRecognizeSimultaneouslyWithGestureRecognizer:"
+            )
+            .entered();
             true
         }
     }
@@ -318,16 +335,19 @@ define_class!(
     unsafe impl UIKeyInput for WinitView {
         #[unsafe(method(hasText))]
         fn has_text(&self) -> bool {
+            let _entered = debug_span!("hasText").entered();
             true
         }
 
         #[unsafe(method(insertText:))]
         fn insert_text(&self, text: &NSString) {
+            let _entered = debug_span!("insertText:").entered();
             self.handle_insert_text(text)
         }
 
         #[unsafe(method(deleteBackward))]
         fn delete_backward(&self) {
+            let _entered = debug_span!("deleteBackward").entered();
             self.handle_delete_backward()
         }
     }

winit-uikit/src/view_controller.rs

@@ -7,6 +7,7 @@ use objc2_ui_kit::{
     UIDevice, UIInterfaceOrientationMask, UIRectEdge, UIResponder, UIStatusBarStyle,
     UIUserInterfaceIdiom, UIView, UIViewController,
 };
+use tracing::trace_span;
 
 use crate::{ScreenEdge, StatusBarStyle, ValidOrientations, WindowAttributesIos};
 
@@ -28,31 +29,37 @@ define_class!(
     impl WinitViewController {
         #[unsafe(method(shouldAutorotate))]
         fn should_autorotate(&self) -> bool {
+            let _entered = trace_span!("shouldAutorotate").entered();
             true
         }
 
         #[unsafe(method(prefersStatusBarHidden))]
         fn prefers_status_bar_hidden(&self) -> bool {
+            let _entered = trace_span!("prefersStatusBarHidden").entered();
             self.ivars().prefers_status_bar_hidden.get()
         }
 
         #[unsafe(method(preferredStatusBarStyle))]
         fn preferred_status_bar_style(&self) -> UIStatusBarStyle {
+            let _entered = trace_span!("preferredStatusBarStyle").entered();
             self.ivars().preferred_status_bar_style.get()
         }
 
         #[unsafe(method(prefersHomeIndicatorAutoHidden))]
         fn prefers_home_indicator_auto_hidden(&self) -> bool {
+            let _entered = trace_span!("prefersHomeIndicatorAutoHidden").entered();
             self.ivars().prefers_home_indicator_auto_hidden.get()
         }
 
         #[unsafe(method(supportedInterfaceOrientations))]
         fn supported_orientations(&self) -> UIInterfaceOrientationMask {
+            let _entered = trace_span!("supportedInterfaceOrientations").entered();
             self.ivars().supported_orientations.get()
         }
 
         #[unsafe(method(preferredScreenEdgesDeferringSystemGestures))]
         fn preferred_screen_edges_deferring_system_gestures(&self) -> UIRectEdge {
+            let _entered = trace_span!("preferredScreenEdgesDeferringSystemGestures").entered();
             self.ivars().preferred_screen_edges_deferring_system_gestures.get()
         }
     }

winit-uikit/src/window.rs

@@ -16,7 +16,7 @@ use objc2_ui_kit::{
     UIApplication, UICoordinateSpace, UIEdgeInsets, UIResponder, UIScreen,
     UIScreenOverscanCompensation, UIViewController, UIWindow,
 };
-use tracing::{debug, warn};
+use tracing::{debug, debug_span, warn};
 use winit_core::cursor::Cursor;
 use winit_core::error::{NotSupportedError, RequestError};
 use winit_core::event::WindowEvent;
@@ -46,6 +46,7 @@ define_class!(
     impl WinitUIWindow {
         #[unsafe(method(becomeKeyWindow))]
         fn become_key_window(&self) {
+            let _entered = debug_span!("becomeKeyWindow").entered();
             let mtm = MainThreadMarker::new().unwrap();
             app_state::handle_nonuser_event(mtm, EventWrapper::Window {
                 window_id: self.id(),
@@ -56,6 +57,7 @@ define_class!(
 
         #[unsafe(method(resignKeyWindow))]
         fn resign_key_window(&self) {
+            let _entered = debug_span!("resignKeyWindow").entered();
             let mtm = MainThreadMarker::new().unwrap();
             app_state::handle_nonuser_event(mtm, EventWrapper::Window {
                 window_id: self.id(),

winit-web/src/monitor.rs

@@ -526,7 +526,7 @@ impl MonitorHandler {
                     },
                 };
 
-                // Notifying `Future`s is not dependant on the lifetime of the runner,
+                // Notifying `Future`s is not dependent on the lifetime of the runner,
                 // because they can outlive it.
                 if let Some(runner) = runner.upgrade() {
                     if let Some(details) = details {
@@ -761,7 +761,7 @@ impl MonitorPermissionFuture {
         wasm_bindgen_futures::spawn_local(async move {
             match future.await {
                 Ok(details) => {
-                    // Notifying `Future`s is not dependant on the lifetime of the runner, because
+                    // Notifying `Future`s is not dependent on the lifetime of the runner, because
                     // they can outlive it.
                     notifier.notify(Ok(()));
 

winit-win32/src/keyboard_layout.rs

@@ -387,11 +387,7 @@ impl LayoutCache {
                 let unicode = Self::to_unicode_string(&key_state, vk, scancode, locale_id);
                 let key = match unicode {
                     ToUnicodeResult::Str(str) => Key::Character(SmolStr::new(str)),
-                    ToUnicodeResult::Dead(dead_char) => {
-                        // println!("{:?} - {:?} produced dead {:?}", key_code, mod_state,
-                        // dead_char);
-                        Key::Dead(dead_char)
-                    },
+                    ToUnicodeResult::Dead(dead_char) => Key::Dead(dead_char),
                     ToUnicodeResult::None => {
                         let has_alt = mod_state.contains(WindowsModifiers::ALT);
                         let has_ctrl = mod_state.contains(WindowsModifiers::CONTROL);

winit-x11/src/util/mod.rs

@@ -66,7 +66,6 @@ impl XConnection {
     // All util functions that abstract an async function will return a `Flusher`.
     pub fn flush_requests(&self) -> Result<(), XError> {
         unsafe { (self.xlib.XFlush)(self.display) };
-        // println!("XFlush");
         // This isn't necessarily a useful time to check for errors (since our request hasn't
         // necessarily been processed yet)
         self.check_errors()
@@ -74,7 +73,6 @@ impl XConnection {
 
     pub fn sync_with_server(&self) -> Result<(), XError> {
         unsafe { (self.xlib.XSync)(self.display, ffi::False) };
-        // println!("XSync");
         self.check_errors()
     }
 }

winit/build.rs

@@ -1,7 +1,9 @@
 use cfg_aliases::cfg_aliases;
 
+// Only relevant for examples and Winit, our usage of println! is fine here.
+#[allow(clippy::disallowed_macros)]
 fn main() {
-    // The script doesn't depend on our code.
+    // Dummy invocation to enable change-tracking in build scripts.
     println!("cargo:rerun-if-changed=build.rs");
 
     // Setup cfg aliases.

winit/examples/application.rs

@@ -10,7 +10,7 @@ use std::fmt::Debug;
 use std::num::NonZeroU32;
 use std::sync::Arc;
 use std::sync::mpsc::{self, Receiver, Sender};
-#[cfg(not(web_platform))]
+#[cfg(not(target_family = "wasm"))]
 use std::time::Instant;
 use std::{fmt, mem};
 
@@ -18,7 +18,7 @@ use cursor_icon::CursorIcon;
 use rwh_06::{DisplayHandle, HasDisplayHandle};
 use softbuffer::{Context, Surface};
 use tracing::{error, info};
-#[cfg(web_platform)]
+#[cfg(target_family = "wasm")]
 use web_time::Instant;
 use winit::application::ApplicationHandler;
 use winit::cursor::{Cursor, CustomCursor, CustomCursorSource};
@@ -29,13 +29,15 @@ use winit::event_loop::{ActiveEventLoop, EventLoop};
 use winit::icon::{Icon, RgbaIcon};
 use winit::keyboard::{Key, ModifiersState};
 use winit::monitor::Fullscreen;
-#[cfg(macos_platform)]
+#[cfg(all(target_vendor = "apple", not(target_os = "macos")))]
+use winit::platform::ios::WindowExtIOS;
+#[cfg(target_os = "macos")]
 use winit::platform::macos::{OptionAsAlt, WindowAttributesMacOS, WindowExtMacOS};
 #[cfg(any(x11_platform, wayland_platform))]
 use winit::platform::startup_notify::{self, EventLoopExtStartupNotify, WindowExtStartupNotify};
 #[cfg(wayland_platform)]
 use winit::platform::wayland::{ActiveEventLoopExtWayland, WindowAttributesWayland};
-#[cfg(web_platform)]
+#[cfg(target_family = "wasm")]
 use winit::platform::web::{ActiveEventLoopExtWeb, WindowAttributesWeb};
 #[cfg(x11_platform)]
 use winit::platform::x11::{ActiveEventLoopExtX11, WindowAttributesX11};
@@ -52,7 +54,7 @@ mod fill;
 const BORDER_SIZE: f64 = 20.;
 
 fn main() -> Result<(), Box<dyn Error>> {
-    #[cfg(web_platform)]
+    #[cfg(target_family = "wasm")]
     console_error_panic_hook::set_once();
 
     tracing_init::init();
@@ -61,7 +63,7 @@ fn main() -> Result<(), Box<dyn Error>> {
     let (sender, receiver) = mpsc::channel();
 
     // Wire the user event from another thread.
-    #[cfg(not(web_platform))]
+    #[cfg(not(target_family = "wasm"))]
     {
         let event_loop_proxy = event_loop.create_proxy();
         let sender = sender.clone();
@@ -143,34 +145,68 @@ impl Application {
 
         #[cfg(x11_platform)]
         if event_loop.is_x11() {
-            window_attributes = window_attributes
-                .with_platform_attributes(Box::new(window_attributes_x11(event_loop)?));
+            let mut attrs = WindowAttributesX11::default();
+
+            if let Some(token) = event_loop.read_token_from_env() {
+                startup_notify::reset_activation_token_env();
+                info!("Using token {:?} to activate a window", token);
+                attrs = attrs.with_activation_token(token);
+            }
+
+            match std::env::var("X11_VISUAL_ID") {
+                Ok(visual_id_str) => {
+                    info!("Using X11 visual id {visual_id_str}");
+                    let visual_id = visual_id_str.parse().expect("invalid X11_VISUAL_ID");
+                    attrs = attrs.with_x11_visual(visual_id);
+                },
+                Err(_) => {
+                    info!("Set the X11_VISUAL_ID env var to request specific X11 visual")
+                },
+            }
+
+            match std::env::var("X11_SCREEN_ID") {
+                Ok(screen_id_str) => {
+                    info!("Placing the window on X11 screen {screen_id_str}");
+                    let screen_id = screen_id_str.parse().expect("invalid X11_SCREEN_ID");
+                    attrs = attrs.with_x11_screen(screen_id);
+                },
+                Err(_) => {
+                    info!("Set the X11_SCREEN_ID env var to place the window on non-default screen")
+                },
+            }
+
+            window_attributes = window_attributes.with_platform_attributes(Box::new(attrs));
         }
 
         #[cfg(wayland_platform)]
         if event_loop.is_wayland() {
-            window_attributes = window_attributes
-                .with_platform_attributes(Box::new(window_attributes_wayland(event_loop)));
+            let mut attrs = WindowAttributesWayland::default();
+
+            if let Some(token) = event_loop.read_token_from_env() {
+                startup_notify::reset_activation_token_env();
+                info!("Using token {:?} to activate a window", token);
+                attrs = attrs.with_activation_token(token);
+            }
+
+            window_attributes = window_attributes.with_platform_attributes(Box::new(attrs));
         }
 
-        #[cfg(macos_platform)]
+        #[cfg(target_os = "macos")]
         if let Some(tab_id) = _tab_id {
-            let window_attributes_macos =
-                Box::new(WindowAttributesMacOS::default().with_tabbing_identifier(&tab_id));
-            window_attributes = window_attributes.with_platform_attributes(window_attributes_macos);
+            let attrs = WindowAttributesMacOS::default().with_tabbing_identifier(&tab_id);
+            window_attributes = window_attributes.with_platform_attributes(Box::new(attrs));
         }
 
-        #[cfg(web_platform)]
+        #[cfg(target_family = "wasm")]
         {
-            window_attributes =
-                window_attributes.with_platform_attributes(Box::new(window_attributes_web()));
+            let attrs = WindowAttributesWeb::default().with_append(true);
+            window_attributes = window_attributes.with_platform_attributes(Box::new(attrs));
         }
 
         let window = event_loop.create_window(window_attributes)?;
 
-        #[cfg(ios_platform)]
+        #[cfg(all(target_vendor = "apple", not(target_os = "macos")))]
         {
-            use winit::platform::ios::WindowExtIOS;
             window.recognize_doubletap_gesture(true);
             window.recognize_pinch_gesture(true);
             window.recognize_rotation_gesture(true);
@@ -186,7 +222,7 @@ impl Application {
 
     fn handle_action_from_proxy(&mut self, _event_loop: &dyn ActiveEventLoop, action: Action) {
         match action {
-            #[cfg(web_platform)]
+            #[cfg(target_family = "wasm")]
             Action::DumpMonitors => self.dump_monitors(_event_loop),
             Action::Message => {
                 info!("User wake up");
@@ -234,11 +270,11 @@ impl Application {
             Action::ToggleResizable => window.toggle_resizable(),
             Action::ToggleDecorations => window.toggle_decorations(),
             Action::ToggleFullscreen => window.toggle_fullscreen(),
-            #[cfg(macos_platform)]
+            #[cfg(target_os = "macos")]
             Action::ToggleSimpleFullscreen => {
                 window.window.set_simple_fullscreen(!window.window.simple_fullscreen());
             },
-            #[cfg(macos_platform)]
+            #[cfg(target_os = "macos")]
             Action::ToggleBorderlessGame => {
                 let current = window.window.is_borderless_game();
                 window.window.set_borderless_game(!current);
@@ -253,13 +289,13 @@ impl Application {
                     error!("Error creating custom cursor: {err}");
                 }
             },
-            #[cfg(web_platform)]
+            #[cfg(target_family = "wasm")]
             Action::UrlCustomCursor => {
                 if let Err(err) = window.url_custom_cursor(event_loop) {
                     error!("Error creating custom cursor from URL: {err}");
                 }
             },
-            #[cfg(web_platform)]
+            #[cfg(target_family = "wasm")]
             Action::AnimationCustomCursor => {
                 if let Err(err) = self
                     .custom_cursors
@@ -274,7 +310,7 @@ impl Application {
             Action::DragResizeWindow => window.drag_resize_window(),
             Action::ShowWindowMenu => window.show_menu(),
             Action::PrintHelp => self.print_help(),
-            #[cfg(macos_platform)]
+            #[cfg(target_os = "macos")]
             Action::CycleOptionAsAlt => window.cycle_option_as_alt(),
             Action::SetTheme(theme) => {
                 window.window.set_theme(theme);
@@ -282,7 +318,7 @@ impl Application {
                 let actual_theme = theme.or_else(|| window.window.theme()).unwrap_or(Theme::Dark);
                 window.set_draw_theme(actual_theme);
             },
-            #[cfg(macos_platform)]
+            #[cfg(target_os = "macos")]
             Action::CreateNewTab => {
                 let tab_id = window.window.tabbing_identifier();
                 if let Err(err) = self.create_window(event_loop, Some(tab_id)) {
@@ -290,7 +326,7 @@ impl Application {
                 }
             },
             Action::RequestResize => window.swap_dimensions(),
-            #[cfg(web_platform)]
+            #[cfg(target_family = "wasm")]
             Action::DumpMonitors => {
                 let future = event_loop.request_detailed_monitor_permission();
                 let proxy = event_loop.create_proxy();
@@ -304,7 +340,7 @@ impl Application {
                     proxy.wake_up();
                 });
             },
-            #[cfg(not(web_platform))]
+            #[cfg(not(target_family = "wasm"))]
             Action::DumpMonitors => self.dump_monitors(event_loop),
             Action::Message => {
                 self.sender.send(Action::Message).unwrap();
@@ -635,7 +671,7 @@ struct WindowState {
     /// The amount of pan of the window.
     panned: PhysicalPosition<f32>,
 
-    #[cfg(macos_platform)]
+    #[cfg(target_os = "macos")]
     option_as_alt: OptionAsAlt,
 
     // Cursor states.
@@ -659,7 +695,7 @@ impl WindowState {
 
         let size = window.surface_size();
         let mut state = Self {
-            #[cfg(macos_platform)]
+            #[cfg(target_os = "macos")]
             option_as_alt: window.option_as_alt(),
             custom_idx: app.custom_cursors.as_ref().map(Vec::len).unwrap_or(1) - 1,
             cursor_grab: CursorGrabMode::None,
@@ -758,7 +794,7 @@ impl WindowState {
         }
     }
 
-    #[cfg(macos_platform)]
+    #[cfg(target_os = "macos")]
     fn cycle_option_as_alt(&mut self) {
         self.option_as_alt = match self.option_as_alt {
             OptionAsAlt::None => OptionAsAlt::OnlyLeft,
@@ -804,7 +840,7 @@ impl WindowState {
     }
 
     /// Custom cursor from an URL.
-    #[cfg(web_platform)]
+    #[cfg(target_family = "wasm")]
     fn url_custom_cursor(
         &mut self,
         event_loop: &dyn ActiveEventLoop,
@@ -817,7 +853,7 @@ impl WindowState {
     }
 
     /// Custom cursor from a URL.
-    #[cfg(web_platform)]
+    #[cfg(target_family = "wasm")]
     fn animation_custom_cursor(
         &mut self,
         event_loop: &dyn ActiveEventLoop,
@@ -1003,27 +1039,27 @@ enum Action {
     ToggleDecorations,
     ToggleResizable,
     ToggleFullscreen,
-    #[cfg(macos_platform)]
+    #[cfg(target_os = "macos")]
     ToggleSimpleFullscreen,
-    #[cfg(macos_platform)]
+    #[cfg(target_os = "macos")]
     ToggleBorderlessGame,
     ToggleMaximize,
     Minimize,
     NextCursor,
     NextCustomCursor,
-    #[cfg(web_platform)]
+    #[cfg(target_family = "wasm")]
     UrlCustomCursor,
-    #[cfg(web_platform)]
+    #[cfg(target_family = "wasm")]
     AnimationCustomCursor,
     CycleCursorGrab,
     PrintHelp,
     DragWindow,
     DragResizeWindow,
     ShowWindowMenu,
-    #[cfg(macos_platform)]
+    #[cfg(target_os = "macos")]
     CycleOptionAsAlt,
     SetTheme(Option<Theme>),
-    #[cfg(macos_platform)]
+    #[cfg(target_os = "macos")]
     CreateNewTab,
     RequestResize,
     DumpMonitors,
@@ -1042,35 +1078,35 @@ impl Action {
             Action::ToggleDecorations => "Toggle decorations",
             Action::ToggleResizable => "Toggle window resizable state",
             Action::ToggleFullscreen => "Toggle fullscreen",
-            #[cfg(macos_platform)]
+            #[cfg(target_os = "macos")]
             Action::ToggleSimpleFullscreen => "Toggle simple fullscreen",
-            #[cfg(macos_platform)]
+            #[cfg(target_os = "macos")]
             Action::ToggleBorderlessGame => "Toggle borderless game mode",
             Action::ToggleMaximize => "Maximize",
             Action::Minimize => "Minimize",
             Action::ToggleResizeIncrements => "Use resize increments when resizing window",
             Action::NextCursor => "Advance the cursor to the next value",
             Action::NextCustomCursor => "Advance custom cursor to the next value",
-            #[cfg(web_platform)]
+            #[cfg(target_family = "wasm")]
             Action::UrlCustomCursor => "Custom cursor from an URL",
-            #[cfg(web_platform)]
+            #[cfg(target_family = "wasm")]
             Action::AnimationCustomCursor => "Custom cursor from an animation",
             Action::CycleCursorGrab => "Cycle through cursor grab mode",
             Action::PrintHelp => "Print help",
             Action::DragWindow => "Start window drag",
             Action::DragResizeWindow => "Start window drag-resize",
             Action::ShowWindowMenu => "Show window menu",
-            #[cfg(macos_platform)]
+            #[cfg(target_os = "macos")]
             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)]
+            #[cfg(target_os = "macos")]
             Action::CreateNewTab => "Create new tab",
             Action::RequestResize => "Request a resize",
-            #[cfg(not(web_platform))]
+            #[cfg(not(target_family = "wasm"))]
             Action::DumpMonitors => "Dump monitor information",
-            #[cfg(web_platform)]
+            #[cfg(target_family = "wasm")]
             Action::DumpMonitors => {
                 "Request permission to query detailed monitor information and dump monitor \
                  information"
@@ -1097,7 +1133,7 @@ fn decode_cursor(bytes: &[u8]) -> CustomCursorSource {
     CustomCursorSource::from_rgba(samples.samples, w, h, w / 2, h / 2).unwrap()
 }
 
-#[cfg(web_platform)]
+#[cfg(target_family = "wasm")]
 fn url_custom_cursor() -> CustomCursorSource {
     use std::sync::atomic::{AtomicU64, Ordering};
 
@@ -1162,60 +1198,6 @@ fn mouse_button_to_string(button: MouseButton) -> Cow<'static, str> {
     .into()
 }
 
-#[cfg(web_platform)]
-fn window_attributes_web() -> WindowAttributesWeb {
-    WindowAttributesWeb::default().with_append(true)
-}
-
-#[cfg(wayland_platform)]
-fn window_attributes_wayland(event_loop: &dyn ActiveEventLoop) -> WindowAttributesWayland {
-    let mut window_attributes = WindowAttributesWayland::default();
-
-    if let Some(token) = event_loop.read_token_from_env() {
-        startup_notify::reset_activation_token_env();
-        info!("Using token {:?} to activate a window", token);
-        window_attributes = window_attributes.with_activation_token(token);
-    }
-
-    window_attributes
-}
-
-#[cfg(x11_platform)]
-fn window_attributes_x11(
-    event_loop: &dyn ActiveEventLoop,
-) -> Result<WindowAttributesX11, Box<dyn Error>> {
-    let mut window_attributes = WindowAttributesX11::default();
-
-    #[cfg(any(x11_platform, wayland_platform))]
-    if let Some(token) = event_loop.read_token_from_env() {
-        startup_notify::reset_activation_token_env();
-        info!("Using token {:?} to activate a window", token);
-        window_attributes = window_attributes.with_activation_token(token);
-    }
-
-    match std::env::var("X11_VISUAL_ID") {
-        Ok(visual_id_str) => {
-            info!("Using X11 visual id {visual_id_str}");
-            let visual_id = visual_id_str.parse()?;
-            window_attributes = window_attributes.with_x11_visual(visual_id);
-        },
-        Err(_) => info!("Set the X11_VISUAL_ID env variable to request specific X11 visual"),
-    }
-
-    match std::env::var("X11_SCREEN_ID") {
-        Ok(screen_id_str) => {
-            info!("Placing the window on X11 screen {screen_id_str}");
-            let screen_id = screen_id_str.parse()?;
-            window_attributes = window_attributes.with_x11_screen(screen_id);
-        },
-        Err(_) => {
-            info!("Set the X11_SCREEN_ID env variable to place the window on non-default screen")
-        },
-    }
-
-    Ok(window_attributes)
-}
-
 /// Cursor list to cycle through.
 const CURSORS: &[CursorIcon] = &[
     CursorIcon::Default,
@@ -1259,7 +1241,7 @@ const KEY_BINDINGS: &[Binding<&'static str>] = &[
     Binding::new("H", ModifiersState::CONTROL, Action::PrintHelp),
     Binding::new("F", ModifiersState::SHIFT, Action::ToggleAnimatedFillColor),
     Binding::new("F", ModifiersState::CONTROL, Action::ToggleFullscreen),
-    #[cfg(macos_platform)]
+    #[cfg(target_os = "macos")]
     Binding::new("F", ModifiersState::ALT, Action::ToggleSimpleFullscreen),
     Binding::new("D", ModifiersState::CONTROL, Action::ToggleDecorations),
     Binding::new("L", ModifiersState::CONTROL, Action::CycleCursorGrab),
@@ -1276,13 +1258,13 @@ const KEY_BINDINGS: &[Binding<&'static str>] = &[
     // C.
     Binding::new("C", ModifiersState::CONTROL, Action::NextCursor),
     Binding::new("C", ModifiersState::ALT, Action::NextCustomCursor),
-    #[cfg(web_platform)]
+    #[cfg(target_family = "wasm")]
     Binding::new(
         "C",
         ModifiersState::CONTROL.union(ModifiersState::SHIFT),
         Action::UrlCustomCursor,
     ),
-    #[cfg(web_platform)]
+    #[cfg(target_family = "wasm")]
     Binding::new(
         "C",
         ModifiersState::ALT.union(ModifiersState::SHIFT),
@@ -1293,11 +1275,11 @@ const KEY_BINDINGS: &[Binding<&'static str>] = &[
     Binding::new("K", ModifiersState::empty(), Action::SetTheme(None)),
     Binding::new("K", ModifiersState::META, Action::SetTheme(Some(Theme::Light))),
     Binding::new("K", ModifiersState::CONTROL, Action::SetTheme(Some(Theme::Dark))),
-    #[cfg(macos_platform)]
+    #[cfg(target_os = "macos")]
     Binding::new("T", ModifiersState::META, Action::CreateNewTab),
-    #[cfg(macos_platform)]
+    #[cfg(target_os = "macos")]
     Binding::new("O", ModifiersState::CONTROL, Action::CycleOptionAsAlt),
-    #[cfg(macos_platform)]
+    #[cfg(target_os = "macos")]
     Binding::new("B", ModifiersState::CONTROL, Action::ToggleBorderlessGame),
     Binding::new("S", ModifiersState::ALT, Action::EmitSurfaceSize),
     Binding::new("S", ModifiersState::CONTROL, Action::Message),

winit/examples/child_window.rs

@@ -1,8 +1,9 @@
-#[cfg(any(x11_platform, macos_platform, windows_platform))]
+#[cfg(any(x11_platform, target_os = "macos", target_os = "windows"))]
 #[allow(deprecated)]
 fn main() -> Result<(), impl std::error::Error> {
     use std::collections::HashMap;
 
+    use tracing::info;
     use winit::application::ApplicationHandler;
     use winit::dpi::{LogicalPosition, LogicalSize, Position};
     use winit::event::{ElementState, KeyEvent, WindowEvent};
@@ -38,7 +39,7 @@ fn main() -> Result<(), impl std::error::Error> {
                 .with_position(Position::Logical(LogicalPosition::new(0.0, 0.0)))
                 .with_surface_size(LogicalSize::new(640.0f32, 480.0f32));
             let window = event_loop.create_window(attributes).unwrap();
-            println!("Parent window id: {:?})", window.id());
+            info!("Parent window id: {:?})", window.id());
             self.parent_window_id = Some(window.id());
 
             self.windows.insert(window.id(), WindowData::new(window, 0xffbbbbbb));
@@ -56,12 +57,12 @@ fn main() -> Result<(), impl std::error::Error> {
                     event_loop.exit();
                 },
                 WindowEvent::PointerEntered { device_id: _, .. } => {
-                    // On x11, println when the cursor entered in a window even if the child window
+                    // On x11, log when the cursor entered in a window even if the child window
                     // is created by some key inputs.
                     // the child windows are always placed at (0, 0) with size (200, 200) in the
                     // parent window, so we also can see this log when we move
                     // the cursor around (200, 200) in parent window.
-                    println!("cursor entered in the window {window_id:?}");
+                    info!("cursor entered in the window {window_id:?}");
                 },
                 WindowEvent::KeyboardInput {
                     event: KeyEvent { state: ElementState::Pressed, .. },
@@ -75,7 +76,7 @@ fn main() -> Result<(), impl std::error::Error> {
                     let child_window =
                         spawn_child_window(parent_window.window.as_ref(), event_loop, child_index);
                     let child_id = child_window.id();
-                    println!("Child window created with id: {child_id:?}");
+                    info!("Child window created with id: {child_id:?}");
                     self.windows.insert(child_id, WindowData::new(child_window, child_color));
                 },
                 WindowEvent::RedrawRequested => {
@@ -120,7 +121,7 @@ fn main() -> Result<(), impl std::error::Error> {
     event_loop.run_app(Application::default())
 }
 
-#[cfg(not(any(x11_platform, macos_platform, windows_platform)))]
+#[cfg(not(any(x11_platform, target_os = "macos", target_os = "windows")))]
 fn main() {
     panic!(
         "This example is supported only on x11, macOS, and Windows, with the `rwh_06` feature \

winit/examples/control_flow.rs

@@ -1,12 +1,13 @@
 #![allow(clippy::single_match)]
 
 use std::thread;
-#[cfg(not(web_platform))]
-use std::time;
+use std::time::Duration;
+#[cfg(not(target_family = "wasm"))]
+use std::time::Instant;
 
-use ::tracing::{info, warn};
-#[cfg(web_platform)]
-use web_time as time;
+use tracing::{info, warn};
+#[cfg(target_family = "wasm")]
+use web_time::Instant;
 use winit::application::ApplicationHandler;
 use winit::event::{ElementState, KeyEvent, StartCause, WindowEvent};
 use winit::event_loop::{ActiveEventLoop, ControlFlow, EventLoop};
@@ -18,8 +19,8 @@ mod fill;
 #[path = "util/tracing.rs"]
 mod tracing;
 
-const WAIT_TIME: time::Duration = time::Duration::from_millis(100);
-const POLL_SLEEP_TIME: time::Duration = time::Duration::from_millis(100);
+const WAIT_TIME: Duration = Duration::from_millis(100);
+const POLL_SLEEP_TIME: Duration = Duration::from_millis(100);
 
 #[derive(Default, Debug, Clone, Copy, PartialEq, Eq)]
 enum Mode {
@@ -30,7 +31,7 @@ enum Mode {
 }
 
 fn main() -> Result<(), impl std::error::Error> {
-    #[cfg(web_platform)]
+    #[cfg(target_family = "wasm")]
     console_error_panic_hook::set_once();
 
     tracing::init();
@@ -129,8 +130,7 @@ impl ApplicationHandler for ControlFlowDemo {
             Mode::Wait => event_loop.set_control_flow(ControlFlow::Wait),
             Mode::WaitUntil => {
                 if !self.wait_cancelled {
-                    event_loop
-                        .set_control_flow(ControlFlow::WaitUntil(time::Instant::now() + WAIT_TIME));
+                    event_loop.set_control_flow(ControlFlow::WaitUntil(Instant::now() + WAIT_TIME));
                 }
             },
             Mode::Poll => {

winit/examples/dnd.rs

@@ -1,5 +1,6 @@
 use std::error::Error;
 
+use tracing::info;
 use winit::application::ApplicationHandler;
 use winit::event::WindowEvent;
 use winit::event_loop::{ActiveEventLoop, EventLoop};
@@ -49,7 +50,7 @@ impl ApplicationHandler for Application {
             | WindowEvent::DragEntered { .. }
             | WindowEvent::DragMoved { .. }
             | WindowEvent::DragDropped { .. } => {
-                println!("{event:?}");
+                info!("{event:?}");
             },
             WindowEvent::RedrawRequested => {
                 let window = self.window.as_ref().unwrap();

winit/examples/ime.rs

@@ -14,7 +14,7 @@ use winit::application::ApplicationHandler;
 use winit::event::{Ime, WindowEvent};
 use winit::event_loop::{ActiveEventLoop, EventLoop};
 use winit::keyboard::{Key, ModifiersState, NamedKey};
-#[cfg(web_platform)]
+#[cfg(target_family = "wasm")]
 use winit::platform::web::WindowAttributesWeb;
 use winit::window::{
     ImeCapabilities, ImeEnableRequest, ImeHint, ImePurpose, ImeRequest, ImeRequestData,
@@ -68,15 +68,15 @@ impl TextInputState {
 
 impl ApplicationHandler for App {
     fn can_create_surfaces(&mut self, event_loop: &dyn ActiveEventLoop) {
-        #[cfg(not(web_platform))]
+        #[cfg(not(target_family = "wasm"))]
         let window_attributes = WindowAttributes::default();
-        #[cfg(web_platform)]
+        #[cfg(target_family = "wasm")]
         let window_attributes = WindowAttributes::default()
             .with_platform_attributes(Box::new(WindowAttributesWeb::default().with_append(true)));
         self.window = match event_loop.create_window(window_attributes) {
             Ok(window) => Some(window),
             Err(err) => {
-                eprintln!("error creating window: {err}");
+                error!("error creating window: {err}");
                 event_loop.exit();
                 return;
             },
@@ -339,14 +339,14 @@ fn preedit_with_cursor_checked(text: &str, cursor: usize, anchor: usize) -> Resu
 }
 
 fn main() -> Result<(), Box<dyn Error>> {
-    #[cfg(web_platform)]
+    #[cfg(target_family = "wasm")]
     console_error_panic_hook::set_once();
 
     tracing_init::init();
 
     let event_loop = EventLoop::new()?;
 
-    println!(
+    info!(
         r#"This showcases the use of an input method engine (IME) by emulating a text edit field.
 Use CTRL+i to toggle IME support.
 Use CTRL+p to cycle content purpose values.

winit/examples/pump_events.rs

@@ -1,12 +1,19 @@
 #![allow(clippy::single_match)]
 
 // Limit this example to only compatible platforms.
-#[cfg(any(windows_platform, macos_platform, x11_platform, wayland_platform, android_platform,))]
+#[cfg(any(
+    target_os = "windows",
+    target_os = "macos",
+    x11_platform,
+    wayland_platform,
+    target_os = "android",
+))]
 fn main() -> std::process::ExitCode {
     use std::process::ExitCode;
     use std::thread::sleep;
     use std::time::Duration;
 
+    use tracing::info;
     use winit::application::ApplicationHandler;
     use winit::event::WindowEvent;
     use winit::event_loop::pump_events::{EventLoopExtPumpEvents, PumpStatus};
@@ -15,6 +22,8 @@ fn main() -> std::process::ExitCode {
 
     #[path = "util/fill.rs"]
     mod fill;
+    #[path = "util/tracing.rs"]
+    mod tracing;
 
     #[derive(Default, Debug)]
     struct PumpDemo {
@@ -33,7 +42,7 @@ fn main() -> std::process::ExitCode {
             _window_id: WindowId,
             event: WindowEvent,
         ) {
-            println!("{event:?}");
+            info!("{event:?}");
 
             let window = match self.window.as_ref() {
                 Some(window) => window,
@@ -51,9 +60,9 @@ fn main() -> std::process::ExitCode {
         }
     }
 
-    let mut event_loop = EventLoop::new().unwrap();
+    tracing::init();
 
-    tracing_subscriber::fmt::init();
+    let mut event_loop = EventLoop::new().unwrap();
 
     let mut app = PumpDemo::default();
 
@@ -69,12 +78,18 @@ fn main() -> std::process::ExitCode {
         //
         // Since `pump_events` doesn't block it will be important to
         // throttle the loop in the app somehow.
-        println!("Update()");
+        info!("Update()");
         sleep(Duration::from_millis(16));
     }
 }
 
-#[cfg(any(ios_platform, web_platform, orbital_platform))]
+#[cfg(not(any(
+    target_os = "windows",
+    target_os = "macos",
+    x11_platform,
+    wayland_platform,
+    target_os = "android",
+)))]
 fn main() {
-    println!("This platform doesn't support pump_events.");
+    panic!("This platform doesn't support pump_events.")
 }

winit/examples/run_on_demand.rs

@@ -1,10 +1,17 @@
 #![allow(clippy::single_match)]
 
 // Limit this example to only compatible platforms.
-#[cfg(any(windows_platform, macos_platform, x11_platform, wayland_platform, orbital_platform))]
+#[cfg(any(
+    target_os = "windows",
+    target_os = "macos",
+    x11_platform,
+    wayland_platform,
+    target_os = "redox"
+))]
 fn main() -> Result<(), Box<dyn std::error::Error>> {
     use std::time::Duration;
 
+    use tracing::info;
     use winit::application::ApplicationHandler;
     use winit::event::WindowEvent;
     use winit::event_loop::run_on_demand::EventLoopExtRunOnDemand;
@@ -13,6 +20,8 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
 
     #[path = "util/fill.rs"]
     mod fill;
+    #[path = "util/tracing.rs"]
+    mod tracing;
 
     #[derive(Default, Debug)]
     struct App {
@@ -44,10 +53,7 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
             event: WindowEvent,
         ) {
             if event == WindowEvent::Destroyed && self.window_id == Some(window_id) {
-                println!(
-                    "--------------------------------------------------------- Window {} Destroyed",
-                    self.idx
-                );
+                info!("Window {} Destroyed", self.idx);
                 self.window_id = None;
                 event_loop.exit();
                 return;
@@ -60,11 +66,7 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
 
             match event {
                 WindowEvent::CloseRequested => {
-                    println!(
-                        "--------------------------------------------------------- Window {} \
-                         CloseRequested",
-                        self.idx
-                    );
+                    info!("Window {} CloseRequested", self.idx);
                     fill::cleanup_window(window.as_ref());
                     self.window = None;
                 },
@@ -76,30 +78,30 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
         }
     }
 
-    tracing_subscriber::fmt::init();
+    tracing::init();
 
     let mut event_loop = EventLoop::new().unwrap();
 
     let mut app = App { idx: 1, ..Default::default() };
     event_loop.run_app_on_demand(&mut app)?;
 
-    println!("--------------------------------------------------------- Finished first loop");
-    println!("--------------------------------------------------------- Waiting 5 seconds");
+    info!("Finished first loop");
+    info!("Waiting 5 seconds");
     std::thread::sleep(Duration::from_secs(5));
 
     app.idx += 1;
     event_loop.run_app_on_demand(&mut app)?;
-    println!("--------------------------------------------------------- Finished second loop");
+    info!("Finished second loop");
     Ok(())
 }
 
 #[cfg(not(any(
-    windows_platform,
-    macos_platform,
+    target_os = "windows",
+    target_os = "macos",
     x11_platform,
     wayland_platform,
-    orbital_platform
+    target_os = "redox"
 )))]
 fn main() {
-    println!("This example is not supported on this platform");
+    panic!("This example is not supported on this platform")
 }

winit/examples/util/fill.rs

@@ -12,11 +12,11 @@ use std::collections::HashMap;
 use std::mem;
 use std::mem::ManuallyDrop;
 use std::num::NonZeroU32;
-#[cfg(not(web_platform))]
+#[cfg(not(target_family = "wasm"))]
 use std::time::Instant;
 
 use softbuffer::{Context, Surface};
-#[cfg(web_platform)]
+#[cfg(target_family = "wasm")]
 use web_time::Instant;
 use winit::window::{Window, WindowId};
 

winit/examples/util/tracing.rs

@@ -1,4 +1,4 @@
-#[cfg(not(web_platform))]
+#[cfg(not(target_family = "wasm"))]
 pub fn init() {
     use tracing_subscriber::filter::{EnvFilter, LevelFilter};
 
@@ -9,7 +9,7 @@ pub fn init() {
         .init();
 }
 
-#[cfg(web_platform)]
+#[cfg(target_family = "wasm")]
 pub fn init() {
     use tracing_subscriber::layer::SubscriberExt;
     use tracing_subscriber::util::SubscriberInitExt;
@@ -23,3 +23,6 @@ pub fn init() {
         )
         .init();
 }
+
+#[allow(unused_imports)]
+pub use ::tracing::*;

winit/examples/window.rs

@@ -1,13 +1,11 @@
 //! Simple winit window example.
 
 use std::error::Error;
-use std::time::Instant;
 
+use tracing::{error, info};
 use winit::application::ApplicationHandler;
 use winit::event::WindowEvent;
 use winit::event_loop::{ActiveEventLoop, EventLoop};
-#[cfg(web_platform)]
-use winit::platform::web::WindowAttributesWeb;
 use winit::window::{Window, WindowAttributes, WindowId};
 
 #[path = "util/fill.rs"]
@@ -22,32 +20,26 @@ struct App {
 
 impl ApplicationHandler for App {
     fn can_create_surfaces(&mut self, event_loop: &dyn ActiveEventLoop) {
-        #[cfg(not(web_platform))]
         let window_attributes = WindowAttributes::default();
-        #[cfg(web_platform)]
-        let window_attributes = WindowAttributes::default()
-            .with_platform_attributes(Box::new(WindowAttributesWeb::default().with_append(true)));
+        #[cfg(target_family = "wasm")]
+        let window_attributes = window_attributes.with_platform_attributes(Box::new(
+            winit::platform::web::WindowAttributesWeb::default().with_append(true),
+        ));
         self.window = match event_loop.create_window(window_attributes) {
             Ok(window) => Some(window),
             Err(err) => {
-                eprintln!("error creating window: {err}");
+                error!("error creating window: {err}");
                 event_loop.exit();
                 return;
             },
         }
     }
 
-    fn window_event(
-        &mut self,
-        event_loop: &dyn ActiveEventLoop,
-        _: WindowId,
-        timestamp: Instant,
-        event: WindowEvent,
-    ) {
-        ::tracing::info!("{:?}: {event:?}", timestamp.elapsed());
+    fn window_event(&mut self, event_loop: &dyn ActiveEventLoop, _: WindowId, event: WindowEvent) {
+        info!("{event:?}");
         match event {
             WindowEvent::CloseRequested => {
-                println!("Close was requested; stopping");
+                info!("Close was requested; stopping");
                 event_loop.exit();
             },
             WindowEvent::SurfaceResized(_) => {
@@ -69,25 +61,15 @@ impl ApplicationHandler for App {
                 fill::fill_window(window.as_ref());
 
                 // For contiguous redraw loop you can request a redraw from here.
-                window.request_redraw();
+                // window.request_redraw();
             },
             _ => (),
         }
     }
-
-    fn device_event(
-        &mut self,
-        _event_loop: &dyn ActiveEventLoop,
-        _device_id: Option<winit::event::DeviceId>,
-        timestamp: Instant,
-        event: winit::event::DeviceEvent,
-    ) {
-        ::tracing::info!("{:?}: {event:?}", timestamp.elapsed());
-    }
 }
 
 fn main() -> Result<(), Box<dyn Error>> {
-    #[cfg(web_platform)]
+    #[cfg(target_family = "wasm")]
     console_error_panic_hook::set_once();
 
     tracing::init();

winit/examples/x11_embed.rs

@@ -11,6 +11,8 @@ fn main() -> Result<(), Box<dyn Error>> {
 
     #[path = "util/fill.rs"]
     mod fill;
+    #[path = "util/tracing.rs"]
+    mod tracing;
 
     #[derive(Debug)]
     pub struct XEmbedDemo {
@@ -58,7 +60,7 @@ fn main() -> Result<(), Box<dyn Error>> {
         .ok_or("Expected a 32-bit X11 window ID as the first argument.")?
         .parse::<u32>()?;
 
-    tracing_subscriber::fmt::init();
+    tracing::init();
     let event_loop = EventLoop::new()?;
 
     Ok(event_loop.run_app(XEmbedDemo { parent_window_id, window: None })?)
@@ -66,6 +68,5 @@ fn main() -> Result<(), Box<dyn Error>> {
 
 #[cfg(not(x11_platform))]
 fn main() -> Result<(), Box<dyn Error>> {
-    println!("This example is only supported on X11 platforms.");
-    Ok(())
+    panic!("This example is only supported on X11 platforms.")
 }

winit/src/changelog/unreleased.md

@@ -46,6 +46,8 @@ changelog entry.
 - On iOS, add Apple Pencil support with force, altitude, and azimuth data.
 - On Redox, add support for missing keyboard scancodes.
 - Implement `Send` and `Sync` for `OwnedDisplayHandle`.
+- Use new macOS 15 cursors for resize icons.
+- On Android, added scancode conversions for more obscure key codes.
 
 ### Changed
 

winit/src/event_loop.rs

@@ -29,7 +29,7 @@ use crate::platform_impl;
 ///
 /// To wake up an `EventLoop` from a another thread, see the [`EventLoopProxy`] docs.
 ///
-/// Note that this cannot be shared across threads (due to platform-dependant logic
+/// Note that this cannot be shared across threads (due to platform-dependent logic
 /// forbidding it), as such it is neither [`Send`] nor [`Sync`]. If you need cross-thread access,
 /// the [`Window`] created from this _can_ be sent to an other thread, and the
 /// [`EventLoopProxy`] allows you to wake up an `EventLoop` from another thread.
@@ -88,7 +88,7 @@ impl EventLoopBuilder {
     )]
     #[inline]
     pub fn build(&mut self) -> Result<EventLoop, EventLoopError> {
-        let _span = tracing::debug_span!("winit::EventLoopBuilder::build").entered();
+        let _entered = tracing::debug_span!("winit::EventLoopBuilder::build").entered();
 
         // Certain platforms accept a mutable reference in their API.
         #[allow(clippy::unnecessary_mut_passed)]
@@ -262,7 +262,7 @@ impl EventLoop {
     ///
     /// [`DeviceEvent`]: crate::event::DeviceEvent
     pub fn listen_device_events(&self, allowed: DeviceEvents) {
-        let _span = tracing::debug_span!(
+        let _entered = tracing::debug_span!(
             "winit::EventLoop::listen_device_events",
             allowed = ?allowed
         )