Add support for double click event to MouseArea (#2602)

* feat(widget/mouse_area): add double_click event

* Run `cargo fmt`

---------

Co-authored-by: Héctor Ramón Jiménez <[email protected]>

widget/src/mouse_area.rs

@@ -22,6 +22,7 @@ pub struct MouseArea<
     content: Element<'a, Message, Theme, Renderer>,
     on_press: Option<Message>,
     on_release: Option<Message>,
+    on_double_click: Option<Message>,
     on_right_press: Option<Message>,
     on_right_release: Option<Message>,
     on_middle_press: Option<Message>,
@@ -48,6 +49,22 @@ impl<'a, Message, Theme, Renderer> MouseArea<'a, Message, Theme, Renderer> {
         self
     }
 
+    /// The message to emit on a double click.
+    ///
+    /// If you use this with [`on_press`]/[`on_release`], those
+    /// event will be emit as normal.
+    ///
+    /// The events stream will be: on_press -> on_release -> on_press
+    /// -> on_double_click -> on_release -> on_press ...
+    ///
+    /// [`on_press`]: Self::on_press
+    /// [`on_release`]: Self::on_release
+    #[must_use]
+    pub fn on_double_click(mut self, message: Message) -> Self {
+        self.on_double_click = Some(message);
+        self
+    }
+
     /// The message to emit on a right button press.
     #[must_use]
     pub fn on_right_press(mut self, message: Message) -> Self {
@@ -121,6 +138,7 @@ struct State {
     is_hovered: bool,
     bounds: Rectangle,
     cursor_position: Option<Point>,
+    previous_click: Option<mouse::Click>,
 }
 
 impl<'a, Message, Theme, Renderer> MouseArea<'a, Message, Theme, Renderer> {
@@ -132,6 +150,7 @@ impl<'a, Message, Theme, Renderer> MouseArea<'a, Message, Theme, Renderer> {
             content: content.into(),
             on_press: None,
             on_release: None,
+            on_double_click: None,
             on_right_press: None,
             on_right_release: None,
             on_middle_press: None,
@@ -347,12 +366,37 @@ fn update<Message: Clone, Theme, Renderer>(
         return event::Status::Ignored;
     }
 
-    if let Some(message) = widget.on_press.as_ref() {
-        if let Event::Mouse(mouse::Event::ButtonPressed(mouse::Button::Left))
-        | Event::Touch(touch::Event::FingerPressed { .. }) = event
-        {
+    if let Event::Mouse(mouse::Event::ButtonPressed(mouse::Button::Left))
+    | Event::Touch(touch::Event::FingerPressed { .. }) = event
+    {
+        let mut captured = false;
+
+        if let Some(message) = widget.on_press.as_ref() {
+            captured = true;
             shell.publish(message.clone());
+        }
+
+        if let Some(position) = cursor_position {
+            if let Some(message) = widget.on_double_click.as_ref() {
+                let new_click = mouse::Click::new(
+                    position,
+                    mouse::Button::Left,
+                    state.previous_click,
+                );
+
+                if matches!(new_click.kind(), mouse::click::Kind::Double) {
+                    shell.publish(message.clone());
+                }
+
+                state.previous_click = Some(new_click);
+
+                // Even if this is not a double click, but the press is nevertheless
+                // processed by us and should not be popup to parent widgets.
+                captured = true;
+            }
+        }
 
+        if captured {
             return event::Status::Captured;
         }
     }