Improve handling of window focus (#830)

Co-authored-by: Daniel McNab <[email protected]>

masonry/src/contexts.rs

@@ -815,6 +815,11 @@ impl_context_method!(
             self.widget_state.has_focus
         }
 
+        /// Whether the window is focused.
+        pub fn is_window_focused(&self) -> bool {
+            self.global_state.window_focused
+        }
+
         /// Whether this widget gets pointer events and hovered status.
         pub fn accepts_pointer_interaction(&self) -> bool {
             self.widget_state.accepts_pointer_interaction

masonry/src/event.rs

@@ -239,8 +239,7 @@ pub enum TextEvent {
     /// Modifier keys (e.g. Shift, Ctrl, Alt) were pressed or released.
     ModifierChange(ModifiersState),
     /// The window took or lost focus.
-    // TODO - Document difference with Update focus change
-    FocusChange(bool),
+    WindowFocusChange(bool),
 }
 
 // TODO - Go into more detail.
@@ -470,7 +469,7 @@ impl TextEvent {
             Self::Ime(Ime::Preedit(s, _)) if s.is_empty() => "Ime::Preedit(\"\")",
             Self::Ime(Ime::Preedit(_, _)) => "Ime::Preedit(\"...\")",
             Self::ModifierChange(_) => "ModifierChange",
-            Self::FocusChange(_) => "FocusChange",
+            Self::WindowFocusChange(_) => "WindowFocusChange",
         }
     }
 
@@ -484,7 +483,7 @@ impl TextEvent {
             Self::Ime(_) => false,
             // Basically every mouse click/scroll event seems to produce a modifier change event.
             Self::ModifierChange(_) => true,
-            Self::FocusChange(_) => false,
+            Self::WindowFocusChange(_) => false,
         }
     }
 }

masonry/src/event_loop_runner.rs

@@ -517,7 +517,7 @@ impl MasonryState<'_> {
             }
             WinitWindowEvent::Focused(new_focus) => {
                 self.render_root
-                    .handle_text_event(TextEvent::FocusChange(new_focus));
+                    .handle_text_event(TextEvent::WindowFocusChange(new_focus));
             }
             WinitWindowEvent::CursorEntered { .. } => {
                 self.render_root

masonry/src/passes/event.rs

@@ -188,7 +188,7 @@ pub(crate) fn run_on_pointer_event_pass(root: &mut RenderRoot, event: &PointerEv
 // --- MARK: TEXT EVENT ---
 /// See the [passes documentation](../doc/05_pass_system.md#event-passes).
 pub(crate) fn run_on_text_event_pass(root: &mut RenderRoot, event: &TextEvent) -> Handled {
-    if matches!(event, TextEvent::FocusChange(false)) {
+    if matches!(event, TextEvent::WindowFocusChange(false)) {
         run_on_pointer_event_pass(root, &PointerEvent::new_pointer_leave());
     }
 
@@ -203,6 +203,10 @@ pub(crate) fn run_on_text_event_pass(root: &mut RenderRoot, event: &TextEvent) -
         debug!("Running ON_TEXT_EVENT pass with {}", event.short_name());
     }
 
+    if let TextEvent::WindowFocusChange(focused) = event {
+        root.global_state.window_focused = *focused;
+    }
+
     let target = root.global_state.focused_widget;
 
     let mut handled = run_event_pass(

masonry/src/render_root.rs

@@ -104,6 +104,9 @@ pub(crate) struct RenderRootState {
     /// This is used to pick the focused widget on Tab events.
     pub(crate) most_recently_clicked_widget: Option<WidgetId>,
 
+    /// Whether the window is focused.
+    pub(crate) window_focused: bool,
+
     /// Widgets that have requested to be scrolled into view.
     pub(crate) scroll_request_targets: Vec<(WidgetId, Rect)>,
 
@@ -260,6 +263,7 @@ impl RenderRoot {
                 focused_path: Vec::new(),
                 next_focused_widget: None,
                 most_recently_clicked_widget: None,
+                window_focused: true,
                 scroll_request_targets: Vec::new(),
                 hovered_path: Vec::new(),
                 pointer_capture_target: None,

masonry/src/widget/text_area.rs

@@ -757,7 +757,7 @@ impl<const EDITABLE: bool> Widget for TextArea<EDITABLE> {
                 }
             }
             // TODO: Set our highlighting colour to a lighter blue as window unfocused
-            TextEvent::FocusChange(_) => {}
+            TextEvent::WindowFocusChange(_) => {}
             TextEvent::Ime(e) => {
                 // TODO: Handle the cursor movement things from https://github.com/rust-windowing/winit/pull/3824
                 let (fctx, lctx) = ctx.text_contexts();