Add non-mut egui::Window::open

crates/egui/src/containers/window.rs

@@ -32,7 +32,7 @@ use super::*;
 #[must_use = "You should call .show()"]
 pub struct Window<'open> {
     title: WidgetText,
-    open: Option<&'open mut bool>,
+    open: Option<Open<'open>>,
     area: Area,
     frame: Option<Frame>,
     resize: Resize,
@@ -42,6 +42,11 @@ pub struct Window<'open> {
     with_title_bar: bool,
 }
 
+enum Open<'open> {
+    Mut(&'open mut bool),
+    NonMut(bool),
+}
+
 impl<'open> Window<'open> {
     /// The window title is used as a unique [`Id`] and must be unique, and should not change.
     /// This is true even if you disable the title bar with `.title_bar(false)`.
@@ -72,14 +77,31 @@ impl<'open> Window<'open> {
         self
     }
 
+    /// Unlike [`Window::open_mut`], calling this function does not display the close button.
+    /// It is functionally equivalent to the following code:
+    ///
+    /// ``` ignore
+    /// if open {
+    ///     // your window code
+    /// }
+    /// ```
+    ///
+    /// The advantage of calling this function instead of using `if open` is that
+    /// this can display the close animation when the window is closed.
+    #[inline]
+    pub fn open(mut self, open: bool) -> Self {
+        self.open = Some(Open::NonMut(open));
+        self
+    }
+
     /// Call this to add a close-button to the window title bar.
     ///
     /// * If `*open == false`, the window will not be visible.
     /// * If `*open == true`, the window will have a close button.
     /// * If the close button is pressed, `*open` will be set to `false`.
     #[inline]
-    pub fn open(mut self, open: &'open mut bool) -> Self {
-        self.open = Some(open);
+    pub fn open_mut(mut self, open: &'open mut bool) -> Self {
+        self.open = Some(Open::Mut(open));
         self
     }
 
@@ -394,7 +416,7 @@ impl<'open> Window<'open> {
     ) -> Option<InnerResponse<Option<R>>> {
         let Window {
             title,
-            open,
+            mut open,
             area,
             frame,
             resize,
@@ -413,7 +435,7 @@ impl<'open> Window<'open> {
         // Add border padding to the inner margin to prevent it from covering the contents
         window_frame.inner_margin += border_padding;
 
-        let is_explicitly_closed = matches!(open, Some(false));
+        let is_explicitly_closed = matches!(open, Some(Open::Mut(false) | Open::NonMut(false)));
         let is_open = !is_explicitly_closed || ctx.memory(|mem| mem.everything_is_visible());
         area.show_open_close_animation(ctx, &window_frame, is_open);
 
@@ -483,6 +505,11 @@ impl<'open> Window<'open> {
             let frame_stroke = window_frame.stroke;
             let mut frame = window_frame.begin(&mut area_content_ui);
 
+            let open = match open.take() {
+                Some(Open::Mut(open)) => Some(open),
+                _ => None,
+            };
+
             let show_close_button = open.is_some();
 
             let where_to_put_header_background = &area_content_ui.painter().add(Shape::Noop);

crates/egui_demo_app/src/backend_panel.rs

@@ -394,28 +394,28 @@ impl EguiWindows {
         }
 
         egui::Window::new("🔧 Settings")
-            .open(settings)
+            .open_mut(settings)
             .vscroll(true)
             .show(ctx, |ui| {
                 ctx.settings_ui(ui);
             });
 
         egui::Window::new("🔍 Inspection")
-            .open(inspection)
+            .open_mut(inspection)
             .vscroll(true)
             .show(ctx, |ui| {
                 ctx.inspection_ui(ui);
             });
 
         egui::Window::new("📝 Memory")
-            .open(memory)
+            .open_mut(memory)
             .resizable(false)
             .show(ctx, |ui| {
                 ctx.memory_ui(ui);
             });
 
         egui::Window::new("📤 Output Events")
-            .open(output_events)
+            .open_mut(output_events)
             .resizable(true)
             .default_width(520.0)
             .show(ctx, |ui| {

crates/egui_demo_app/src/wrap_app.rs

@@ -472,7 +472,7 @@ impl WrapApp {
         if !self.dropped_files.is_empty() {
             let mut open = true;
             egui::Window::new("Dropped files")
-                .open(&mut open)
+                .open_mut(&mut open)
                 .show(ctx, |ui| {
                     for file in &self.dropped_files {
                         let mut info = if let Some(path) = &file.path {

crates/egui_demo_lib/src/demo/about.rs

@@ -12,7 +12,7 @@ impl super::Demo for About {
         egui::Window::new(self.name())
             .default_width(320.0)
             .default_height(480.0)
-            .open(open)
+            .open_mut(open)
             .resizable([true, false])
             .show(ctx, |ui| {
                 use super::View as _;

crates/egui_demo_lib/src/demo/code_editor.rs

@@ -29,7 +29,7 @@ impl super::Demo for CodeEditor {
     fn show(&mut self, ctx: &egui::Context, open: &mut bool) {
         use super::View as _;
         egui::Window::new(self.name())
-            .open(open)
+            .open_mut(open)
             .default_height(500.0)
             .show(ctx, |ui| self.ui(ui));
     }

crates/egui_demo_lib/src/demo/code_example.rs

@@ -112,7 +112,7 @@ impl super::Demo for CodeExample {
     fn show(&mut self, ctx: &egui::Context, open: &mut bool) {
         use super::View;
         egui::Window::new(self.name())
-            .open(open)
+            .open_mut(open)
             .min_width(375.0)
             .default_size([390.0, 500.0])
             .scroll(false)

crates/egui_demo_lib/src/demo/context_menu.rs

@@ -57,7 +57,7 @@ impl super::Demo for ContextMenus {
         egui::Window::new(self.name())
             .vscroll(false)
             .resizable(false)
-            .open(open)
+            .open_mut(open)
             .show(ctx, |ui| self.ui(ui));
     }
 }

crates/egui_demo_lib/src/demo/dancing_strings.rs

@@ -13,7 +13,7 @@ impl super::Demo for DancingStrings {
     fn show(&mut self, ctx: &Context, open: &mut bool) {
         use super::View as _;
         Window::new(self.name())
-            .open(open)
+            .open_mut(open)
             .default_size(vec2(512.0, 256.0))
             .vscroll(false)
             .show(ctx, |ui| self.ui(ui));

crates/egui_demo_lib/src/demo/demo_app_windows.rs

@@ -203,7 +203,7 @@ impl DemoWindows {
                 .default_width(default_width)
                 .default_height(ctx.available_rect().height() - 46.0)
                 .vscroll(true)
-                .open(&mut self.about_is_open)
+                .open_mut(&mut self.about_is_open)
                 .resizable(false)
                 .collapsible(false)
                 .show(ctx, |ui| {

crates/egui_demo_lib/src/demo/drag_and_drop.rs

@@ -30,7 +30,7 @@ impl super::Demo for DragAndDropDemo {
     fn show(&mut self, ctx: &Context, open: &mut bool) {
         use super::View as _;
         Window::new(self.name())
-            .open(open)
+            .open_mut(open)
             .default_size(vec2(256.0, 256.0))
             .vscroll(false)
             .resizable(false)

crates/egui_demo_lib/src/demo/extra_viewport.rs

@@ -27,7 +27,7 @@ impl super::Demo for ExtraViewport {
                     // Not a real viewport
                     egui::Window::new(self.name())
                         .id(id)
-                        .open(open)
+                        .open_mut(open)
                         .show(ctx, |ui| {
                             ui.label("This egui integration does not support multiple viewports");
                         });

crates/egui_demo_lib/src/demo/font_book.rs

@@ -22,10 +22,12 @@ impl super::Demo for FontBook {
     }
 
     fn show(&mut self, ctx: &egui::Context, open: &mut bool) {
-        egui::Window::new(self.name()).open(open).show(ctx, |ui| {
-            use super::View as _;
-            self.ui(ui);
-        });
+        egui::Window::new(self.name())
+            .open_mut(open)
+            .show(ctx, |ui| {
+                use super::View as _;
+                self.ui(ui);
+            });
     }
 }
 

crates/egui_demo_lib/src/demo/frame_demo.rs

@@ -31,7 +31,7 @@ impl super::Demo for FrameDemo {
 
     fn show(&mut self, ctx: &egui::Context, open: &mut bool) {
         egui::Window::new(self.name())
-            .open(open)
+            .open_mut(open)
             .resizable(false)
             .show(ctx, |ui| {
                 use super::View as _;

crates/egui_demo_lib/src/demo/highlighting.rs

@@ -11,7 +11,7 @@ impl super::Demo for Highlighting {
     fn show(&mut self, ctx: &egui::Context, open: &mut bool) {
         egui::Window::new(self.name())
             .default_width(320.0)
-            .open(open)
+            .open_mut(open)
             .show(ctx, |ui| {
                 use super::View as _;
                 self.ui(ui);

crates/egui_demo_lib/src/demo/layout_test.rs

@@ -80,7 +80,7 @@ impl super::Demo for LayoutTest {
 
     fn show(&mut self, ctx: &egui::Context, open: &mut bool) {
         egui::Window::new(self.name())
-            .open(open)
+            .open_mut(open)
             .resizable(false)
             .show(ctx, |ui| {
                 use super::View as _;

crates/egui_demo_lib/src/demo/misc_demo_window.rs

@@ -43,7 +43,7 @@ impl Demo for MiscDemoWindow {
 
     fn show(&mut self, ctx: &Context, open: &mut bool) {
         Window::new(self.name())
-            .open(open)
+            .open_mut(open)
             .vscroll(true)
             .hscroll(true)
             .show(ctx, |ui| self.ui(ui));

crates/egui_demo_lib/src/demo/multi_touch.rs

@@ -28,7 +28,7 @@ impl super::Demo for MultiTouch {
 
     fn show(&mut self, ctx: &egui::Context, open: &mut bool) {
         egui::Window::new(self.name())
-            .open(open)
+            .open_mut(open)
             .default_size(vec2(512.0, 512.0))
             .resizable(true)
             .show(ctx, |ui| {

crates/egui_demo_lib/src/demo/paint_bezier.rs

@@ -163,7 +163,7 @@ impl super::Demo for PaintBezier {
     fn show(&mut self, ctx: &Context, open: &mut bool) {
         use super::View as _;
         Window::new(self.name())
-            .open(open)
+            .open_mut(open)
             .vscroll(false)
             .resizable(false)
             .default_size([300.0, 350.0])

crates/egui_demo_lib/src/demo/painting.rs

@@ -80,7 +80,7 @@ impl super::Demo for Painting {
     fn show(&mut self, ctx: &Context, open: &mut bool) {
         use super::View as _;
         Window::new(self.name())
-            .open(open)
+            .open_mut(open)
             .default_size(vec2(512.0, 512.0))
             .vscroll(false)
             .show(ctx, |ui| self.ui(ui));

crates/egui_demo_lib/src/demo/pan_zoom.rs

@@ -20,7 +20,7 @@ impl super::Demo for PanZoom {
             .default_width(300.0)
             .default_height(300.0)
             .vscroll(false)
-            .open(open);
+            .open_mut(open);
         window.show(ctx, |ui| self.ui(ui));
     }
 }

crates/egui_demo_lib/src/demo/panels.rs

@@ -13,7 +13,7 @@ impl super::Demo for Panels {
             .default_width(600.0)
             .default_height(400.0)
             .vscroll(false)
-            .open(open);
+            .open_mut(open);
         window.show(ctx, |ui| self.ui(ui));
     }
 }

crates/egui_demo_lib/src/demo/plot_demo.rs

@@ -52,7 +52,7 @@ impl super::Demo for PlotDemo {
     fn show(&mut self, ctx: &Context, open: &mut bool) {
         use super::View as _;
         Window::new(self.name())
-            .open(open)
+            .open_mut(open)
             .default_size(vec2(400.0, 400.0))
             .vscroll(false)
             .show(ctx, |ui| self.ui(ui));

crates/egui_demo_lib/src/demo/scrolling.rs

@@ -34,7 +34,7 @@ impl super::Demo for Scrolling {
 
     fn show(&mut self, ctx: &egui::Context, open: &mut bool) {
         egui::Window::new(self.name())
-            .open(open)
+            .open_mut(open)
             .resizable(true)
             .hscroll(false)
             .vscroll(false)

crates/egui_demo_lib/src/demo/sliders.rs

@@ -46,7 +46,7 @@ impl super::Demo for Sliders {
 
     fn show(&mut self, ctx: &egui::Context, open: &mut bool) {
         egui::Window::new(self.name())
-            .open(open)
+            .open_mut(open)
             .resizable(false)
             .show(ctx, |ui| {
                 use super::View as _;

crates/egui_demo_lib/src/demo/strip_demo.rs

@@ -13,7 +13,7 @@ impl super::Demo for StripDemo {
 
     fn show(&mut self, ctx: &egui::Context, open: &mut bool) {
         egui::Window::new(self.name())
-            .open(open)
+            .open_mut(open)
             .resizable(true)
             .default_width(400.0)
             .show(ctx, |ui| {

crates/egui_demo_lib/src/demo/table_demo.rs

@@ -45,7 +45,7 @@ impl super::Demo for TableDemo {
 
     fn show(&mut self, ctx: &egui::Context, open: &mut bool) {
         egui::Window::new(self.name())
-            .open(open)
+            .open_mut(open)
             .default_width(400.0)
             .show(ctx, |ui| {
                 use super::View as _;