Send position on button release

CHANGELOG.md

@@ -63,6 +63,7 @@ And please only add new entries to the top of this list, right below the `# Unre
 - **Breaking:** On Web, `instant` is now replaced by `web_time`.
 - On Windows, port to `windows-sys` version 0.48.0.
 - On Web, fix pen treated as mouse input.
+- On Web, send mouse position on button release as well.
 
 # 0.28.6
 

src/platform_impl/web/event_loop/window_target.rs

@@ -400,14 +400,15 @@ impl<T> EventLoopWindowTarget<T> {
             },
         );
 
-        let runner = self.runner.clone();
-        let runner_touch = self.runner.clone();
-        let modifiers = self.modifiers.clone();
-        let has_focus_clone = has_focus.clone();
         canvas.on_mouse_release(
-            move |pointer_id, button, active_modifiers| {
+            {
+                let runner = self.runner.clone();
+                let modifiers = self.modifiers.clone();
+                let has_focus = has_focus.clone();
+
+                move |pointer_id, position, button, active_modifiers| {
                     let modifiers_changed =
-                    (has_focus_clone.get() && modifiers.get() != active_modifiers).then(|| {
+                        (has_focus.get() && modifiers.get() != active_modifiers).then(|| {
                             modifiers.set(active_modifiers);
                             Event::WindowEvent {
                                 window_id: RootWindowId(id),
@@ -415,7 +416,17 @@ impl<T> EventLoopWindowTarget<T> {
                             }
                         });
 
-                runner.send_events(modifiers_changed.into_iter().chain(iter::once(
+                    // A mouse up 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.
+                    runner.send_events(modifiers_changed.into_iter().chain([
+                        Event::WindowEvent {
+                            window_id: RootWindowId(id),
+                            event: WindowEvent::CursorMoved {
+                                device_id: RootDeviceId(DeviceId(pointer_id)),
+                                position,
+                            },
+                        },
                         Event::WindowEvent {
                             window_id: RootWindowId(id),
                             event: WindowEvent::MouseInput {
@@ -424,8 +435,12 @@ impl<T> EventLoopWindowTarget<T> {
                                 button,
                             },
                         },
-                )));
+                    ]));
+                }
             },
+            {
+                let runner_touch = self.runner.clone();
+
                 move |device_id, location, force| {
                     runner_touch.send_event(Event::WindowEvent {
                         window_id: RootWindowId(id),
@@ -437,6 +452,7 @@ impl<T> EventLoopWindowTarget<T> {
                             location,
                         }),
                     });
+                }
             },
         );
 

src/platform_impl/web/web_sys/canvas.rs

@@ -243,7 +243,7 @@ impl Canvas {
 
     pub fn on_mouse_release<M, T>(&mut self, mouse_handler: M, touch_handler: T)
     where
-        M: 'static + FnMut(i32, MouseButton, ModifiersState),
+        M: 'static + FnMut(i32, PhysicalPosition<f64>, MouseButton, ModifiersState),
         T: 'static + FnMut(i32, PhysicalPosition<f64>, Force),
     {
         match &mut self.mouse_state {

src/platform_impl/web/web_sys/canvas/mouse_handler.rs

@@ -84,7 +84,7 @@ impl MouseHandler {
 
     pub fn on_mouse_release<F>(&mut self, canvas_common: &super::Common, mut handler: F)
     where
-        F: 'static + FnMut(i32, MouseButton, ModifiersState),
+        F: 'static + FnMut(i32, PhysicalPosition<f64>, MouseButton, ModifiersState),
     {
         let on_mouse_leave_handler = self.on_mouse_leave_handler.clone();
         let mouse_capture_state = self.mouse_capture_state.clone();
@@ -110,6 +110,7 @@ impl MouseHandler {
                 event.stop_propagation();
                 handler(
                     0,
+                    event::mouse_position(&event).to_physical(super::super::scale_factor()),
                     event::mouse_button(&event).expect("no mouse button released"),
                     event::mouse_modifiers(&event),
                 );

src/platform_impl/web/web_sys/canvas/pointer_handler.rs

@@ -75,7 +75,7 @@ impl PointerHandler {
         mut mouse_handler: M,
         mut touch_handler: T,
     ) where
-        M: 'static + FnMut(i32, MouseButton, ModifiersState),
+        M: 'static + FnMut(i32, PhysicalPosition<f64>, MouseButton, ModifiersState),
         T: 'static + FnMut(i32, PhysicalPosition<f64>, Force),
     {
         let canvas = canvas_common.raw.clone();
@@ -91,6 +91,7 @@ impl PointerHandler {
                     ),
                     "mouse" => mouse_handler(
                         event.pointer_id(),
+                        event::mouse_position(&event).to_physical(super::super::scale_factor()),
                         event::mouse_button(&event).expect("no mouse button released"),
                         event::mouse_modifiers(&event),
                     ),