WIP

crates/gpui2/src/app.rs

@@ -607,6 +607,20 @@ impl AppContext {
         self.globals_by_type.insert(global_type, lease.global);
     }
 
+    pub fn observe_release<E: 'static>(
+        &mut self,
+        handle: &Handle<E>,
+        mut on_release: impl FnMut(&mut E, &mut AppContext) + Send + Sync + 'static,
+    ) -> Subscription {
+        self.release_listeners.insert(
+            handle.entity_id,
+            Box::new(move |entity, cx| {
+                let entity = entity.downcast_mut().expect("invalid entity type");
+                on_release(entity, cx)
+            }),
+        )
+    }
+
     pub(crate) fn push_text_style(&mut self, text_style: TextStyleRefinement) {
         self.text_style_stack.push(text_style);
     }

crates/gpui2/src/app/model_context.rs

@@ -115,15 +115,11 @@ impl<'a, T: 'static> ModelContext<'a, T> {
         T: Any + Send + Sync,
     {
         let this = self.weak_handle();
-        self.app.release_listeners.insert(
-            handle.entity_id,
-            Box::new(move |entity, cx| {
-                let entity = entity.downcast_mut().expect("invalid entity type");
-                if let Some(this) = this.upgrade() {
-                    this.update(cx, |this, cx| on_release(this, entity, cx));
-                }
-            }),
-        )
+        self.app.observe_release(handle, move |entity, cx| {
+            if let Some(this) = this.upgrade() {
+                this.update(cx, |this, cx| on_release(this, entity, cx));
+            }
+        })
     }
 
     pub fn observe_global<G: 'static>(

crates/gpui2/src/window.rs

@@ -1,7 +1,7 @@
 use crate::{
     px, size, Action, AnyBox, AnyDrag, AnyView, AppContext, AsyncWindowContext, AvailableSpace,
-    Bounds, BoxShadow, Context, Corners, DevicePixels, DispatchContext, DisplayId, ExternalPaths,
-    Edges, Effect, Element, EntityId, EventEmitter, FileDropEvent, FocusEvent, FontId,
+    Bounds, BoxShadow, Context, Corners, DevicePixels, DispatchContext, DisplayId, Edges, Effect,
+    Element, EntityId, EventEmitter, ExternalPaths, FileDropEvent, FocusEvent, FontId,
     GlobalElementId, GlyphId, Handle, Hsla, ImageData, InputEvent, IsZero, KeyListener, KeyMatch,
     KeyMatcher, Keystroke, LayoutId, MainThread, MainThreadOnly, Modifiers, MonochromeSprite,
     MouseButton, MouseDownEvent, MouseMoveEvent, MouseUpEvent, Path, Pixels, PlatformAtlas,
@@ -1517,22 +1517,14 @@ impl<'a, 'w, V: 'static> ViewContext<'a, 'w, V> {
         &mut self,
         handle: &Handle<T>,
         mut on_release: impl FnMut(&mut V, &mut T, &mut ViewContext<'_, '_, V>) + Send + Sync + 'static,
-    ) -> Subscription
-    where
-        V: Any + Send + Sync,
-    {
+    ) -> Subscription {
         let this = self.handle();
         let window_handle = self.window.handle;
-        self.app.release_listeners.insert(
-            handle.entity_id,
-            Box::new(move |entity, cx| {
-                let entity = entity.downcast_mut().expect("invalid entity type");
-                // todo!("are we okay with silently swallowing the error?")
-                let _ = cx.update_window(window_handle.id, |cx| {
-                    this.update(cx, |this, cx| on_release(this, entity, cx))
-                });
-            }),
-        )
+        self.app.observe_release(handle, move |entity, cx| {
+            let _ = cx.update_window(window_handle.id, |cx| {
+                this.update(cx, |this, cx| on_release(this, entity, cx))
+            });
+        })
     }
 
     pub fn notify(&mut self) {