Show how to close a child viewport in the example

crates/eframe/src/epi/mod.rs

@@ -123,6 +123,7 @@ pub trait App {
     ///
     /// This is called for the root viewport ([`egui::ViewportId::ROOT`]).
     /// Use [`egui::Context::show_viewport`] to spawn additional viewports (windows).
+    /// (A "viewport" in egui means an native OS window).
     fn update(&mut self, ctx: &egui::Context, frame: &mut Frame);
 
     /// Get a handle to the app.

crates/eframe/src/native/epi_integration.rs

@@ -85,7 +85,7 @@ pub fn window_builder<E>(
         ..
     } = native_options;
 
-    let mut viewport_builder = egui::ViewportBuilder::ROOT
+    let mut viewport_builder = egui::ViewportBuilder::DEFAULTS
         .with_title(title)
         .with_decorations(*decorated)
         .with_fullscreen(*fullscreen)

crates/egui-winit/src/lib.rs

@@ -201,18 +201,16 @@ impl State {
         let screen_size_in_pixels = screen_size_in_pixels(window);
         let screen_size_in_points = screen_size_in_pixels / pixels_per_point;
 
-        let getting_info = !window.is_minimized().unwrap_or_else(|| {
-            eprintln!("Cannot determine the Viewport/native window minimized state");
-            true
-        });
+        self.egui_input.screen_rect = (screen_size_in_points.x > 0.0
+            && screen_size_in_points.y > 0.0)
+            .then(|| Rect::from_min_size(Pos2::ZERO, screen_size_in_points));
 
-        self.egui_input.screen_rect = if getting_info {
-            Some(egui::Rect::from_min_size(Pos2::ZERO, screen_size_in_points))
-        } else {
-            None
+        let has_a_position = match window.is_minimized() {
+            None | Some(true) => false,
+            Some(false) => true,
         };
 
-        let inner_pos_px = if getting_info {
+        let inner_pos_px = if has_a_position {
             window
                 .inner_position()
                 .map(|pos| Pos2::new(pos.x as f32, pos.y as f32))
@@ -221,7 +219,7 @@ impl State {
             None
         };
 
-        let outer_pos_px = if getting_info {
+        let outer_pos_px = if has_a_position {
             window
                 .outer_position()
                 .map(|pos| Pos2::new(pos.x as f32, pos.y as f32))
@@ -230,14 +228,14 @@ impl State {
             None
         };
 
-        let inner_size_px = if getting_info {
+        let inner_size_px = if has_a_position {
             let size = window.inner_size();
             Some(Vec2::new(size.width as f32, size.height as f32))
         } else {
             None
         };
 
-        let outer_size_px = if getting_info {
+        let outer_size_px = if has_a_position {
             let size = window.outer_size();
             Some(Vec2::new(size.width as f32, size.height as f32))
         } else {

crates/egui/src/data/input.rs

@@ -75,6 +75,7 @@ pub struct RawInput {
 impl Default for RawInput {
     fn default() -> Self {
         Self {
+            viewport: ViewportInfo::default(),
             screen_rect: None,
             pixels_per_point: None,
             max_texture_side: None,
@@ -85,7 +86,6 @@ impl Default for RawInput {
             hovered_files: Default::default(),
             dropped_files: Default::default(),
             focused: true, // integrations opt into global focus tracking
-            viewport: ViewportInfo::default(),
         }
     }
 }
@@ -97,6 +97,7 @@ impl RawInput {
     /// * [`Self::dropped_files`] is moved.
     pub fn take(&mut self) -> RawInput {
         RawInput {
+            viewport: self.viewport.take(),
             screen_rect: self.screen_rect.take(),
             pixels_per_point: self.pixels_per_point.take(),
             max_texture_side: self.max_texture_side.take(),
@@ -107,13 +108,13 @@ impl RawInput {
             hovered_files: self.hovered_files.clone(),
             dropped_files: std::mem::take(&mut self.dropped_files),
             focused: self.focused,
-            viewport: self.viewport.take(),
         }
     }
 
     /// Add on new input.
     pub fn append(&mut self, newer: Self) {
         let Self {
+            viewport,
             screen_rect,
             pixels_per_point,
             max_texture_side,
@@ -124,13 +125,12 @@ impl RawInput {
             mut hovered_files,
             mut dropped_files,
             focused,
-            viewport,
         } = newer;
 
+        self.viewport = viewport;
         self.screen_rect = screen_rect.or(self.screen_rect);
         self.pixels_per_point = pixels_per_point.or(self.pixels_per_point);
         self.max_texture_side = max_texture_side.or(self.max_texture_side);
-        self.viewport = viewport;
         self.time = time; // use latest time
         self.predicted_dt = predicted_dt; // use latest dt
         self.modifiers = modifiers; // use latest

crates/egui/src/memory.rs

@@ -79,7 +79,7 @@ pub struct Memory {
     #[cfg_attr(feature = "persistence", serde(skip))]
     pub(crate) new_font_definitions: Option<epaint::text::FontDefinitions>,
 
-    // Current viewport
+    // Current active viewport
     #[cfg_attr(feature = "persistence", serde(skip))]
     pub(crate) viewport_id: ViewportId,
 
@@ -96,7 +96,6 @@ pub struct Memory {
 
     // -------------------------------------------------
     // Per-viewport:
-    #[cfg_attr(feature = "persistence", serde(skip))]
     areas: ViewportIdMap<Areas>,
 
     #[cfg_attr(feature = "persistence", serde(skip))]

crates/egui/src/viewport.rs

@@ -135,7 +135,7 @@ pub struct ViewportBuilder {
 
 impl ViewportBuilder {
     /// Default settings for the root viewport.
-    pub const ROOT: Self = Self {
+    pub const DEFAULTS: Self = Self {
         title: None,
         name: None,
         position: None,
@@ -154,18 +154,12 @@ impl ViewportBuilder {
         min_inner_size: None,
         max_inner_size: None,
         drag_and_drop: Some(true),
-        close_button: Some(false), // We disable the close button by default because we haven't implemented closing of child viewports yet
+        close_button: Some(true),
         minimize_button: Some(true),
         maximize_button: Some(true),
         hittest: Some(true),
     };
 
-    /// Default settings for a new child viewport.
-    pub const CHILD: Self = Self {
-        close_button: Some(false), // We disable the close button by default because we haven't implemented closing of child viewports yet
-        ..Self::ROOT
-    };
-
     /// Empty settings for everything.
     ///
     /// If used the first frame, backend-specific defaults will be used.