Merge pull request #1341 from nicksenger/fix/component-overlay-rebuild

fix: prevent building component overlay with stale layout

lazy/src/component.rs

@@ -410,9 +410,7 @@ where
                         Some(
                             CacheBuilder {
                                 element: state.view(),
-                                overlay_builder: |element| {
-                                    element.overlay(layout, renderer)
-                                },
+                                overlay_builder: |_| None,
                             }
                             .build(),
                         )

lazy/src/pure/component.rs

@@ -464,16 +464,7 @@ where
                     instance_ref_builder: |instance| instance.state.borrow(),
                     tree: overlay.tree,
                     types: PhantomData,
-                    overlay_builder: |instance, tree| {
-                        instance
-                            .as_ref()
-                            .unwrap()
-                            .borrow_element()
-                            .as_ref()
-                            .unwrap()
-                            .as_widget()
-                            .overlay(&mut tree.children[0], layout, renderer)
-                    },
+                    overlay_builder: |_, _| None,
                 }
                 .build(),
             );

native/src/shell.rs

@@ -31,6 +31,11 @@ impl<'a, Message> Shell<'a, Message> {
         }
     }
 
+    /// Returns whether the current layout is invalid or not.
+    pub fn is_layout_invalid(&self) -> bool {
+        self.is_layout_invalid
+    }
+
     /// Publish the given `Message` for an application to process it.
     pub fn publish(&mut self, message: Message) {
         self.messages.push(message);

native/src/user_interface.rs

@@ -177,40 +177,61 @@ where
         clipboard: &mut dyn Clipboard,
         messages: &mut Vec<Message>,
     ) -> (State, Vec<event::Status>) {
+        use std::mem::ManuallyDrop;
+
         let mut state = State::Updated;
+        let mut manual_overlay = ManuallyDrop::new(
+            self.root.overlay(Layout::new(&self.base), renderer),
+        );
 
-        let (base_cursor, overlay_statuses) = if let Some(mut overlay) =
-            self.root.overlay(Layout::new(&self.base), renderer)
-        {
+        let (base_cursor, overlay_statuses) = if manual_overlay.is_some() {
             let bounds = self.bounds;
+
+            let mut overlay = manual_overlay.as_mut().unwrap();
             let mut layout = overlay.layout(renderer, bounds);
+            let mut event_statuses = Vec::new();
 
-            let event_statuses = events
-                .iter()
-                .cloned()
-                .map(|event| {
-                    let mut shell = Shell::new(messages);
+            for event in events.iter().cloned() {
+                let mut shell = Shell::new(messages);
 
-                    let event_status = overlay.on_event(
-                        event,
-                        Layout::new(&layout),
-                        cursor_position,
-                        renderer,
-                        clipboard,
-                        &mut shell,
+                let event_status = overlay.on_event(
+                    event,
+                    Layout::new(&layout),
+                    cursor_position,
+                    renderer,
+                    clipboard,
+                    &mut shell,
+                );
+
+                event_statuses.push(event_status);
+
+                if shell.is_layout_invalid() {
+                    let _ = ManuallyDrop::into_inner(manual_overlay);
+
+                    self.base = renderer.layout(
+                        &self.root,
+                        &layout::Limits::new(Size::ZERO, self.bounds),
+                    );
+
+                    manual_overlay = ManuallyDrop::new(
+                        self.root.overlay(Layout::new(&self.base), renderer),
                     );
 
+                    if manual_overlay.is_none() {
+                        break;
+                    }
+
+                    overlay = manual_overlay.as_mut().unwrap();
+
                     shell.revalidate_layout(|| {
                         layout = overlay.layout(renderer, bounds);
                     });
+                }
 
-                    if shell.are_widgets_invalid() {
-                        state = State::Outdated;
-                    }
-
-                    event_status
-                })
-                .collect();
+                if shell.are_widgets_invalid() {
+                    state = State::Outdated;
+                }
+            }
 
             let base_cursor = if layout.bounds().contains(cursor_position) {
                 // TODO: Type-safe cursor availability
@@ -226,6 +247,8 @@ where
             (cursor_position, vec![event::Status::Ignored; events.len()])
         };
 
+        let _ = ManuallyDrop::into_inner(manual_overlay);
+
         let event_statuses = events
             .iter()
             .cloned()