feat(cef): implement traffic light positioning (#14660)

* feat(cef): implement traffic light positioning

* handle X axis as well

crates/tauri-runtime-cef/src/cef_impl.rs

@@ -714,6 +714,7 @@ wrap_window_delegate! {
     attributes: Arc<RefCell<crate::CefWindowBuilder>>,
     last_emitted_position: RefCell<PhysicalPosition<i32>>,
     last_emitted_size: RefCell<PhysicalSize<u32>>,
+    context: Context<T>
   }
 
   impl ViewDelegate {
@@ -937,6 +938,19 @@ wrap_window_delegate! {
         if a.visible.unwrap_or(true) {
           window.show();
         }
+
+        // Set traffic light position on macOS after window is fully created
+        // by posting a task to the UI thread to avoid issues with early setting
+        #[cfg(target_os = "macos")]
+        if let Some(pos) = a.traffic_light_position {
+          let window_message = WindowMessage::SetTrafficLightPosition(pos);
+          let message = Message::Window {
+            window_id: self.window_id,
+            message: window_message,
+          };
+
+          send_message_task(&self.context, message);
+        }
       }
     }
 
@@ -1017,6 +1031,11 @@ wrap_window_delegate! {
     ) {
       let (Some(window), Some(bounds)) = (window, bounds) else { return; };
 
+      #[cfg(target_os = "macos")]
+      if let Some(pos) = &self.attributes.borrow().traffic_light_position {
+        apply_traffic_light_position(window.window_handle(), pos);
+      }
+
       // Update autoresize overlay bounds (moved from on_layout_changed)
       if let Some(app_window) = self.windows.borrow().get(&self.window_id) {
         for wrapper in &app_window.webviews {
@@ -2335,7 +2354,13 @@ fn handle_window_message<T: UserEvent>(
       // TODO: Implement title bar style
     }
     WindowMessage::SetTrafficLightPosition(_position) => {
-      // TODO: Implement traffic light position
+      #[cfg(target_os = "macos")]
+      if let Some(app_window) = context.windows.borrow().get(&window_id) {
+        app_window.attributes.borrow_mut().traffic_light_position = Some(_position);
+        if let Some(window) = app_window.window() {
+          apply_traffic_light_position(window.window_handle(), &_position);
+        }
+      }
     }
     WindowMessage::SetTheme(_theme) => {
       // TODO: Implement theme
@@ -2608,6 +2633,7 @@ pub(crate) fn create_window<T: UserEvent>(
     attributes.clone(),
     RefCell::new(Default::default()),
     RefCell::new(Default::default()),
+    context.clone(),
   );
 
   let window = window_create_top_level(Some(&mut delegate)).expect("Failed to create window");
@@ -2664,6 +2690,11 @@ wrap_task! {
   }
 }
 
+fn send_message_task<T: UserEvent>(context: &Context<T>, message: Message<T>) {
+  let mut task = SendMessageTask::new(context.clone(), Arc::new(RefCell::new(message)));
+  cef::post_task(sys::cef_thread_id_t::TID_UI.into(), Some(&mut task));
+}
+
 fn send_window_event<T: UserEvent>(
   window_id: WindowId,
   windows: &Arc<RefCell<HashMap<WindowId, AppWindow>>>,
@@ -3166,3 +3197,50 @@ pub(crate) fn ensure_valid_content_view(
   // No replacement needed; return the original handle
   window_handle
 }
+
+#[cfg(target_os = "macos")]
+fn apply_traffic_light_position(window: *mut std::ffi::c_void, position: &Position) {
+  use objc2::msg_send;
+  use objc2::rc::Retained;
+  use objc2_app_kit::{NSView, NSWindowButton};
+
+  let nsview = unsafe { Retained::<NSView>::retain(window as _) };
+  let Some(nsview) = nsview else {
+    return;
+  };
+
+  let Some(nswindow) = nsview.window() else {
+    return;
+  };
+
+  let Some(close) = nswindow.standardWindowButton(NSWindowButton::CloseButton) else {
+    return;
+  };
+  let Some(miniaturize) = nswindow.standardWindowButton(NSWindowButton::MiniaturizeButton) else {
+    return;
+  };
+  let Some(zoom) = nswindow.standardWindowButton(NSWindowButton::ZoomButton) else {
+    return;
+  };
+
+  let pos = position.to_logical::<f64>(nswindow.backingScaleFactor() as f64);
+  let (x, y) = (pos.x, pos.y);
+
+  let title_bar_container_view = unsafe { close.superview().unwrap().superview().unwrap() };
+
+  let close_rect = NSView::frame(&close);
+  let title_bar_frame_height = close_rect.size.height + y;
+  let mut title_bar_rect = NSView::frame(&title_bar_container_view);
+  title_bar_rect.size.height = title_bar_frame_height;
+  title_bar_rect.origin.y = nswindow.frame().size.height - title_bar_frame_height;
+  let _: () = unsafe { msg_send![&title_bar_container_view, setFrame: title_bar_rect] };
+
+  let window_buttons = vec![close, miniaturize.clone(), zoom];
+  let space_between = NSView::frame(&miniaturize).origin.x - close_rect.origin.x;
+
+  for (i, button) in window_buttons.into_iter().enumerate() {
+    let mut rect = NSView::frame(&button);
+    rect.origin.x = x + (i as f64 * space_between);
+    unsafe { button.setFrameOrigin(rect.origin) };
+  }
+}

crates/tauri/src/webview/webview_window.rs

@@ -859,10 +859,14 @@ impl<'a, R: Runtime, M: Manager<R>> WebviewWindowBuilder<'a, R, M> {
   #[cfg(target_os = "macos")]
   #[must_use]
   pub fn traffic_light_position<P: Into<Position>>(mut self, position: P) -> Self {
+    let position = position.into();
+
+    self.window_builder = self.window_builder.traffic_light_position(position.clone());
+
     self.webview_builder.webview_attributes = self
       .webview_builder
       .webview_attributes
-      .traffic_light_position(position.into());
+      .traffic_light_position(position);
     self
   }
 
@@ -2213,6 +2217,15 @@ impl<R: Runtime> WebviewWindow<R> {
     self.window.set_title_bar_style(style)
   }
 
+  /// Sets the position of the traffic light buttons. **macOS only**.
+  ///
+  /// ## Platform-specific
+  ///
+  /// - **macOS only**.
+  pub fn set_traffic_light_position(&self, position: Position) -> crate::Result<()> {
+    self.window.set_traffic_light_position(position)
+  }
+
   /// Sets the theme for this window.
   ///
   /// ## Platform-specific

crates/tauri/src/window/mod.rs

@@ -857,6 +857,14 @@ impl<'a, R: Runtime, M: Manager<R>> WindowBuilder<'a, R, M> {
     self
   }
 
+  /// Sets the [`crate::TitleBarStyle`].
+  #[cfg(target_os = "macos")]
+  #[must_use]
+  pub fn traffic_light_position<P: Into<Position>>(mut self, position: P) -> Self {
+    self.window_builder = self.window_builder.traffic_light_position(position);
+    self
+  }
+
   /// Hide the window title.
   #[cfg(target_os = "macos")]
   #[must_use]
@@ -2174,6 +2182,19 @@ tauri::Builder::default()
       .map_err(Into::into)
   }
 
+  /// Sets the position of the traffic light buttons. **macOS only**.
+  ///
+  /// ## Platform-specific
+  ///
+  /// - **macOS only**.
+  pub fn set_traffic_light_position(&self, position: Position) -> crate::Result<()> {
+    self
+      .window
+      .dispatcher
+      .set_traffic_light_position(position)
+      .map_err(Into::into)
+  }
+
   /// Sets the theme for this window.
   ///
   /// ## Platform-specific