On Windows and MacOS, add Window::has_focus

CHANGELOG.md

@@ -8,6 +8,7 @@ And please only add new entries to the top of this list, right below the `# Unre
 
 # Unreleased
 
+- Add `Window::has_focus`.
 - On Windows, fix `Window::set_minimized(false)` not working for windows minimized by `Win + D` hotkey.
 - **Breaking:** On Web, touch input no longer fires `WindowEvent::Cursor*`, `WindowEvent::MouseInput`, or `DeviceEvent::MouseMotion` like other platforms, but instead it fires `WindowEvent::Touch`.
 - **Breaking:** Removed platform specific `WindowBuilder::with_parent` API in favor of `WindowBuilder::with_parent_window`.

src/platform_impl/android/mod.rs

@@ -5,7 +5,7 @@ use std::{
     hash::Hash,
     sync::{
         atomic::{AtomicBool, Ordering},
-        mpsc, Arc,
+        mpsc, Arc, RwLock,
     },
     time::{Duration, Instant},
 };
@@ -14,6 +14,7 @@ use android_activity::input::{InputEvent, KeyAction, Keycode, MotionAction};
 use android_activity::{
     AndroidApp, AndroidAppWaker, ConfigurationRef, InputStatus, MainEvent, Rect,
 };
+use once_cell::sync::Lazy;
 use raw_window_handle::{
     AndroidDisplayHandle, HasRawWindowHandle, RawDisplayHandle, RawWindowHandle,
 };
@@ -27,6 +28,8 @@ use crate::{
     window::{self, CursorGrabMode, ResizeDirection, Theme, WindowButtons, WindowLevel},
 };
 
+static HAS_FOCUS: Lazy<RwLock<bool>> = Lazy::new(|| RwLock::new(true));
+
 fn ndk_keycode_to_virtualkeycode(keycode: Keycode) -> Option<event::VirtualKeyCode> {
     match keycode {
         Keycode::A => Some(VirtualKeyCode::A),
@@ -394,6 +397,7 @@ impl<T: 'static> EventLoop<T> {
                     warn!("TODO: find a way to notify application of content rect change");
                 }
                 MainEvent::GainedFocus => {
+                    *HAS_FOCUS.write().unwrap() = true;
                     sticky_exit_callback(
                         event::Event::WindowEvent {
                             window_id: window::WindowId(WindowId),
@@ -405,6 +409,7 @@ impl<T: 'static> EventLoop<T> {
                     );
                 }
                 MainEvent::LostFocus => {
+                    *HAS_FOCUS.write().unwrap() = false;
                     sticky_exit_callback(
                         event::Event::WindowEvent {
                             window_id: window::WindowId(WindowId),
@@ -1064,6 +1069,10 @@ impl Window {
         None
     }
 
+    pub fn has_focus(&self) -> bool {
+        *HAS_FOCUS.read().unwrap()
+    }
+
     pub fn title(&self) -> String {
         String::new()
     }

src/platform_impl/ios/uikit/window.rs

@@ -28,5 +28,8 @@ extern_methods!(
 
         #[sel(makeKeyAndVisible)]
         pub fn makeKeyAndVisible(&self);
+
+        #[sel(isKeyWindow)]
+        pub fn isKeyWindow(&self) -> bool;
     }
 );

src/platform_impl/ios/window.rs

@@ -348,6 +348,10 @@ impl Inner {
         None
     }
 
+    pub fn has_focus(&self) -> bool {
+        self.window.isKeyWindow()
+    }
+
     #[inline]
     pub fn set_theme(&self, _theme: Option<Theme>) {
         warn!("`Window::set_theme` is ignored on iOS");

src/platform_impl/linux/mod.rs

@@ -605,6 +605,10 @@ impl Window {
     }
 
     #[inline]
+    pub fn has_focus(&self) -> bool {
+        x11_or_wayland!(match self; Window(window) => window.has_focus())
+    }
+
     pub fn title(&self) -> String {
         x11_or_wayland!(match self; Window(window) => window.title())
     }

src/platform_impl/linux/wayland/seat/keyboard/handlers.rs

@@ -1,5 +1,7 @@
 //! Handling of various keyboard events.
 
+use std::sync::atomic::Ordering;
+
 use sctk::reexports::client::protocol::wl_keyboard::KeyState;
 
 use sctk::seat::keyboard::Event as KeyboardEvent;
@@ -22,6 +24,9 @@ pub(super) fn handle_keyboard(
         KeyboardEvent::Enter { surface, .. } => {
             let window_id = wayland::make_wid(&surface);
 
+            let window_handle = winit_state.window_map.get_mut(&window_id).unwrap();
+            window_handle.has_focus.store(true, Ordering::Relaxed);
+
             // Window gained focus.
             event_sink.push_window_event(WindowEvent::Focused(true), window_id);
 
@@ -44,6 +49,9 @@ pub(super) fn handle_keyboard(
                 );
             }
 
+            let window_handle = winit_state.window_map.get_mut(&window_id).unwrap();
+            window_handle.has_focus.store(false, Ordering::Relaxed);
+
             // Window lost focus.
             event_sink.push_window_event(WindowEvent::Focused(false), window_id);
 

src/platform_impl/linux/wayland/window/mod.rs

@@ -79,6 +79,9 @@ pub struct Window {
 
     /// Grabbing mode.
     cursor_grab_mode: Mutex<CursorGrabMode>,
+
+    /// Whether the window has keyboard focus.
+    has_focus: Arc<AtomicBool>,
 }
 
 impl Window {
@@ -244,6 +247,7 @@ impl Window {
         window.surface().commit();
 
         let size = Arc::new(Mutex::new(LogicalSize::new(width, height)));
+        let has_focus = Arc::new(AtomicBool::new(true));
 
         // We should trigger redraw and commit the surface for the newly created window.
         let mut window_user_request = WindowUserRequest::new();
@@ -258,6 +262,7 @@ impl Window {
             &event_loop_window_target.env,
             window,
             size.clone(),
+            has_focus.clone(),
             window_requests.clone(),
         );
 
@@ -318,6 +323,7 @@ impl Window {
             resizeable: AtomicBool::new(attributes.resizable),
             decorated: AtomicBool::new(attributes.decorations),
             cursor_grab_mode: Mutex::new(CursorGrabMode::None),
+            has_focus,
         };
 
         Ok(window)
@@ -650,6 +656,10 @@ impl Window {
     }
 
     #[inline]
+    pub fn has_focus(&self) -> bool {
+        self.has_focus.load(Ordering::Relaxed)
+    }
+
     pub fn title(&self) -> String {
         String::new()
     }

src/platform_impl/linux/wayland/window/shim.rs

@@ -1,5 +1,6 @@
 use std::cell::Cell;
 use std::mem::ManuallyDrop;
+use std::sync::atomic::AtomicBool;
 use std::sync::{Arc, Mutex};
 
 use sctk::reexports::client::protocol::wl_compositor::WlCompositor;
@@ -154,6 +155,9 @@ pub struct WindowHandle {
     /// Whether the window is resizable.
     pub is_resizable: Cell<bool>,
 
+    /// Whether the window has keyboard focus.
+    pub has_focus: Arc<AtomicBool>,
+
     /// Allow IME events for that window.
     pub ime_allowed: Cell<bool>,
 
@@ -187,6 +191,7 @@ impl WindowHandle {
         env: &Environment<WinitEnv>,
         window: Window<WinitFrame>,
         size: Arc<Mutex<LogicalSize<u32>>>,
+        has_focus: Arc<AtomicBool>,
         pending_window_requests: Arc<Mutex<Vec<WindowRequest>>>,
     ) -> Self {
         let xdg_activation = env.get_global::<XdgActivationV1>();
@@ -209,6 +214,7 @@ impl WindowHandle {
             attention_requested: Cell::new(false),
             compositor,
             ime_allowed: Cell::new(false),
+            has_focus,
         }
     }
 

src/platform_impl/linux/x11/event_processor.rs

@@ -930,6 +930,10 @@ impl<T: 'static> EventProcessor<T> {
                             let window_id = mkwid(xev.event);
                             let position = PhysicalPosition::new(xev.event_x, xev.event_y);
 
+                            if let Some(window) = self.with_window(xev.event, Arc::clone) {
+                                window.shared_state_lock().has_focus = true;
+                            }
+
                             callback(Event::WindowEvent {
                                 window_id,
                                 event: Focused(true),
@@ -1002,6 +1006,10 @@ impl<T: 'static> EventProcessor<T> {
                                 event: WindowEvent::ModifiersChanged(ModifiersState::empty()),
                             });
 
+                            if let Some(window) = self.with_window(xev.event, Arc::clone) {
+                                window.shared_state_lock().has_focus = false;
+                            }
+
                             callback(Event::WindowEvent {
                                 window_id,
                                 event: Focused(false),

src/platform_impl/linux/x11/window.rs

@@ -55,6 +55,7 @@ pub struct SharedState {
     pub resize_increments: Option<Size>,
     pub base_size: Option<Size>,
     pub visibility: Visibility,
+    pub has_focus: bool,
 }
 
 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
@@ -94,6 +95,7 @@ impl SharedState {
             max_inner_size: None,
             resize_increments: None,
             base_size: None,
+            has_focus: true,
         })
     }
 }
@@ -1602,6 +1604,10 @@ impl UnownedWindow {
     }
 
     #[inline]
+    pub fn has_focus(&self) -> bool {
+        self.shared_state_lock().has_focus
+    }
+
     pub fn title(&self) -> String {
         String::new()
     }

src/platform_impl/macos/appkit/window.rs

@@ -192,6 +192,9 @@ extern_methods!(
         #[sel(isVisible)]
         pub fn isVisible(&self) -> bool;
 
+        #[sel(isKeyWindow)]
+        pub fn isKeyWindow(&self) -> bool;
+
         #[sel(isZoomed)]
         pub fn isZoomed(&self) -> bool;
 

src/platform_impl/macos/window.rs

@@ -1215,6 +1215,10 @@ impl WinitWindow {
     }
 
     #[inline]
+    pub fn has_focus(&self) -> bool {
+        self.isKeyWindow()
+    }
+
     pub fn set_theme(&self, theme: Option<Theme>) {
         set_ns_theme(theme);
         self.lock_shared_state("set_theme").current_theme = theme.or_else(|| Some(get_ns_theme()));

src/platform_impl/orbital/window.rs

@@ -393,6 +393,11 @@ impl Window {
         None
     }
 
+    #[inline]
+    pub fn has_focus(&self) -> bool {
+        false
+    }
+
     #[inline]
     pub fn set_theme(&self, _theme: Option<window::Theme>) {}
 }

src/platform_impl/web/event_loop/window_target.rs

@@ -56,6 +56,7 @@ impl<T> EventLoopWindowTarget<T> {
         canvas: &Rc<RefCell<backend::Canvas>>,
         id: WindowId,
         prevent_default: bool,
+        has_focus: Rc<RefCell<bool>>,
     ) {
         self.runner.add_canvas(RootWindowId(id), canvas);
         let mut canvas = canvas.borrow_mut();
@@ -65,7 +66,9 @@ impl<T> EventLoopWindowTarget<T> {
         canvas.on_touch_end(prevent_default);
 
         let runner = self.runner.clone();
+        let has_focus_clone = has_focus.clone();
         canvas.on_blur(move || {
+            *has_focus_clone.borrow_mut() = false;
             runner.send_event(Event::WindowEvent {
                 window_id: RootWindowId(id),
                 event: WindowEvent::Focused(false),
@@ -73,7 +76,9 @@ impl<T> EventLoopWindowTarget<T> {
         });
 
         let runner = self.runner.clone();
+        let has_focus_clone = has_focus.clone();
         canvas.on_focus(move || {
+            *has_focus_clone.borrow_mut() = true;
             runner.send_event(Event::WindowEvent {
                 window_id: RootWindowId(id),
                 event: WindowEvent::Focused(true),
@@ -191,6 +196,8 @@ impl<T> EventLoopWindowTarget<T> {
         let runner_touch = self.runner.clone();
         canvas.on_mouse_press(
             move |pointer_id, position, button, modifiers| {
+                *has_focus.borrow_mut() = true;
+
                 // A mouse down event may come in without any prior CursorMoved events,
                 // therefore we should send a CursorMoved event to make sure that the
                 // user code has the correct cursor position.

src/platform_impl/web/window.rs

@@ -23,6 +23,7 @@ pub struct Window {
     register_redraw_request: Box<dyn Fn()>,
     resize_notify_fn: Box<dyn Fn(PhysicalSize<u32>)>,
     destroy_fn: Option<Box<dyn FnOnce()>>,
+    has_focus: Rc<RefCell<bool>>,
 }
 
 impl Window {
@@ -42,7 +43,8 @@ impl Window {
 
         let register_redraw_request = Box::new(move || runner.request_redraw(RootWI(id)));
 
-        target.register(&canvas, id, prevent_default);
+        let has_focus = Rc::new(RefCell::new(false));
+        target.register(&canvas, id, prevent_default, has_focus.clone());
 
         let runner = target.runner.clone();
         let resize_notify_fn = Box::new(move |new_size| {
@@ -62,6 +64,7 @@ impl Window {
             register_redraw_request,
             resize_notify_fn,
             destroy_fn: Some(destroy_fn),
+            has_focus,
         };
 
         backend::set_canvas_size(
@@ -399,6 +402,10 @@ impl Window {
     }
 
     #[inline]
+    pub fn has_focus(&self) -> bool {
+        *self.has_focus.borrow()
+    }
+
     pub fn title(&self) -> String {
         String::new()
     }

src/platform_impl/windows/window.rs

@@ -773,6 +773,11 @@ impl Window {
     }
 
     #[inline]
+    pub fn has_focus(&self) -> bool {
+        let window_state = self.window_state.lock().unwrap();
+        window_state.has_active_focus()
+    }
+
     pub fn title(&self) -> String {
         let len = unsafe { GetWindowTextLengthW(self.window.0) } + 1;
         let mut buf = vec![0; len as usize];

src/window.rs

@@ -1022,6 +1022,16 @@ impl Window {
         self.window.focus_window()
     }
 
+    /// Gets whether the window has keyboard focus.
+    ///
+    /// This queries the same state information as [`WindowEvent::Focused`].
+    ///
+    /// [`WindowEvent::Focused`]: crate::event::WindowEvent::Focused
+    #[inline]
+    pub fn has_focus(&self) -> bool {
+        self.window.has_focus()
+    }
+
     /// Requests user attention to the window, this has no effect if the application
     /// is already focused. How requesting for user attention manifests is platform dependent,
     /// see [`UserAttentionType`] for details.