Replace `event::Status` in `Widget::on_event` with `Shell::capture_event`

6 files changed, 49 insertions, 41 deletions

diff --git a/core/src/element.rs b/core/src/element.rs
index 6ebb8a15..8276b70c 100644
--- a/core/src/element.rs
+++ b/core/src/element.rs
@@ -1,4 +1,3 @@
-use crate::event::{self, Event};
 use crate::layout;
 use crate::mouse;
 use crate::overlay;
@@ -6,8 +5,8 @@ use crate::renderer;
 use crate::widget;
 use crate::widget::tree::{self, Tree};
 use crate::{
-    Border, Clipboard, Color, Layout, Length, Rectangle, Shell, Size, Vector,
-    Widget,
+    Border, Clipboard, Color, Event, Layout, Length, Rectangle, Shell, Size,
+    Vector, Widget,
 };
 
 use std::borrow::Borrow;
@@ -319,11 +318,11 @@ where
         clipboard: &mut dyn Clipboard,
         shell: &mut Shell<'_, B>,
         viewport: &Rectangle,
-    ) -> event::Status {
+    ) {
         let mut local_messages = Vec::new();
         let mut local_shell = Shell::new(&mut local_messages);
 
-        let status = self.widget.on_event(
+        self.widget.on_event(
             tree,
             event,
             layout,
@@ -335,8 +334,6 @@ where
         );
 
         shell.merge(local_shell, &self.mapper);
-
-        status
     }
 
     fn draw(
@@ -457,10 +454,10 @@ where
         clipboard: &mut dyn Clipboard,
         shell: &mut Shell<'_, Message>,
         viewport: &Rectangle,
-    ) -> event::Status {
+    ) {
         self.element.widget.on_event(
             state, event, layout, cursor, renderer, clipboard, shell, viewport,
-        )
+        );
     }
 
     fn draw(
diff --git a/core/src/overlay.rs b/core/src/overlay.rs
index f09de831..e063bb94 100644
--- a/core/src/overlay.rs
+++ b/core/src/overlay.rs
@@ -5,13 +5,12 @@ mod group;
 pub use element::Element;
 pub use group::Group;
 
-use crate::event::{self, Event};
 use crate::layout;
 use crate::mouse;
 use crate::renderer;
 use crate::widget;
 use crate::widget::Tree;
-use crate::{Clipboard, Layout, Point, Rectangle, Shell, Size, Vector};
+use crate::{Clipboard, Event, Layout, Point, Rectangle, Shell, Size, Vector};
 
 /// An interactive component that can be displayed on top of other widgets.
 pub trait Overlay<Message, Theme, Renderer>
@@ -65,8 +64,7 @@ where
         _renderer: &Renderer,
         _clipboard: &mut dyn Clipboard,
         _shell: &mut Shell<'_, Message>,
-    ) -> event::Status {
-        event::Status::Ignored
+    ) {
     }
 
     /// Returns the current [`mouse::Interaction`] of the [`Overlay`].
diff --git a/core/src/overlay/element.rs b/core/src/overlay/element.rs
index 32e987a3..4a242213 100644
--- a/core/src/overlay/element.rs
+++ b/core/src/overlay/element.rs
@@ -1,11 +1,10 @@
 pub use crate::Overlay;
 
-use crate::event::{self, Event};
 use crate::layout;
 use crate::mouse;
 use crate::renderer;
 use crate::widget;
-use crate::{Clipboard, Layout, Point, Rectangle, Shell, Size};
+use crate::{Clipboard, Event, Layout, Point, Rectangle, Shell, Size};
 
 /// A generic [`Overlay`].
 #[allow(missing_debug_implementations)]
@@ -58,9 +57,9 @@ where
         renderer: &Renderer,
         clipboard: &mut dyn Clipboard,
         shell: &mut Shell<'_, Message>,
-    ) -> event::Status {
+    ) {
         self.overlay
-            .on_event(event, layout, cursor, renderer, clipboard, shell)
+            .on_event(event, layout, cursor, renderer, clipboard, shell);
     }
 
     /// Returns the current [`mouse::Interaction`] of the [`Element`].
@@ -157,11 +156,11 @@ where
         renderer: &Renderer,
         clipboard: &mut dyn Clipboard,
         shell: &mut Shell<'_, B>,
-    ) -> event::Status {
+    ) {
         let mut local_messages = Vec::new();
         let mut local_shell = Shell::new(&mut local_messages);
 
-        let event_status = self.content.on_event(
+        self.content.on_event(
             event,
             layout,
             cursor,
@@ -171,8 +170,6 @@ where
         );
 
         shell.merge(local_shell, self.mapper);
-
-        event_status
     }
 
     fn mouse_interaction(
diff --git a/core/src/overlay/group.rs b/core/src/overlay/group.rs
index 6541d311..11ebd579 100644
--- a/core/src/overlay/group.rs
+++ b/core/src/overlay/group.rs
@@ -1,4 +1,3 @@
-use crate::event;
 use crate::layout;
 use crate::mouse;
 use crate::overlay;
@@ -81,21 +80,17 @@ where
         renderer: &Renderer,
         clipboard: &mut dyn Clipboard,
         shell: &mut Shell<'_, Message>,
-    ) -> event::Status {
-        self.children
-            .iter_mut()
-            .zip(layout.children())
-            .map(|(child, layout)| {
-                child.on_event(
-                    event.clone(),
-                    layout,
-                    cursor,
-                    renderer,
-                    clipboard,
-                    shell,
-                )
-            })
-            .fold(event::Status::Ignored, event::Status::merge)
+    ) {
+        for (child, layout) in self.children.iter_mut().zip(layout.children()) {
+            child.on_event(
+                event.clone(),
+                layout,
+                cursor,
+                renderer,
+                clipboard,
+                shell,
+            );
+        }
     }
 
     fn draw(
diff --git a/core/src/shell.rs b/core/src/shell.rs
index 7a92a2be..12ebbaa8 100644
--- a/core/src/shell.rs
+++ b/core/src/shell.rs
@@ -1,3 +1,4 @@
+use crate::event;
 use crate::time::Instant;
 use crate::window;
 
@@ -10,6 +11,7 @@ use crate::window;
 #[derive(Debug)]
 pub struct Shell<'a, Message> {
     messages: &'a mut Vec<Message>,
+    event_status: event::Status,
     redraw_request: Option<window::RedrawRequest>,
     is_layout_invalid: bool,
     are_widgets_invalid: bool,
@@ -20,6 +22,7 @@ impl<'a, Message> Shell<'a, Message> {
     pub fn new(messages: &'a mut Vec<Message>) -> Self {
         Self {
             messages,
+            event_status: event::Status::Ignored,
             redraw_request: None,
             is_layout_invalid: false,
             are_widgets_invalid: false,
@@ -36,6 +39,24 @@ impl<'a, Message> Shell<'a, Message> {
         self.messages.push(message);
     }
 
+    /// Marks the current event as captured. Prevents "event bubbling".
+    ///
+    /// A widget should capture an event when no ancestor should
+    /// handle it.
+    pub fn capture_event(&mut self) {
+        self.event_status = event::Status::Captured;
+    }
+
+    /// Returns the current [`event::Status`] of the [`Shell`].
+    pub fn event_status(&self) -> event::Status {
+        self.event_status
+    }
+
+    /// Returns whether the current event has been captured.
+    pub fn is_event_captured(&self) -> bool {
+        self.event_status == event::Status::Captured
+    }
+
     /// Requests a new frame to be drawn as soon as possible.
     pub fn request_redraw(&mut self) {
         self.redraw_request = Some(window::RedrawRequest::NextFrame);
@@ -114,5 +135,7 @@ impl<'a, Message> Shell<'a, Message> {
 
         self.are_widgets_invalid =
             self.are_widgets_invalid || other.are_widgets_invalid;
+
+        self.event_status = self.event_status.merge(other.event_status);
     }
 }
diff --git a/core/src/widget.rs b/core/src/widget.rs
index 9cfff83d..bddf99cc 100644
--- a/core/src/widget.rs
+++ b/core/src/widget.rs
@@ -10,12 +10,11 @@ pub use operation::Operation;
 pub use text::Text;
 pub use tree::Tree;
 
-use crate::event::{self, Event};
 use crate::layout::{self, Layout};
 use crate::mouse;
 use crate::overlay;
 use crate::renderer;
-use crate::{Clipboard, Length, Rectangle, Shell, Size, Vector};
+use crate::{Clipboard, Event, Length, Rectangle, Shell, Size, Vector};
 
 /// A component that displays information and allows interaction.
 ///
@@ -122,8 +121,7 @@ where
         _clipboard: &mut dyn Clipboard,
         _shell: &mut Shell<'_, Message>,
         _viewport: &Rectangle,
-    ) -> event::Status {
-        event::Status::Ignored
+    ) {
     }
 
     /// Returns the current [`mouse::Interaction`] of the [`Widget`].