Popover content supports setting the maximum width (#180)

Before:

![image](https://github.com/user-attachments/assets/cde8dc35-f59d-474c-8386-b6f666e83249)

After:

![image](https://github.com/user-attachments/assets/d5db1bed-5c2d-4efd-81e4-a0d13e48b035)

crates/story/src/popup_story.rs

@@ -185,10 +185,12 @@ impl Render for PopupStory {
                             Popover::new("info-top-left")
                                 .trigger(Button::new("info-top-left", cx).label("Top Left"))
                                 .content(|cx| {
+                                    cx.new_view(|cx| {
                                         PopoverContent::new(cx, |cx| {
                                             v_flex()
                                                 .gap_4()
                                                 .child("Hello, this is a Popover.")
+                                                .w(px(400.))
                                                 .child(Divider::horizontal())
                                                 .child(
                                                     Button::new("info1", cx)
@@ -197,8 +199,9 @@ impl Render for PopupStory {
                                                         .small(),
                                                 )
                                                 .into_any()
+                                        }).max_w(px(600.))
+                                    })
                                 })
-                                }),
                         ),
                     )
                     .child(
@@ -206,6 +209,7 @@ impl Render for PopupStory {
                             .anchor(AnchorCorner::TopRight)
                             .trigger(Button::new("info-top-right", cx).label("Top Right"))
                             .content(|cx| {
+                                cx.new_view(|cx|
                                     PopoverContent::new(cx, |cx| {
                                         v_flex()
                                             .gap_4()
@@ -219,7 +223,7 @@ impl Render for PopupStory {
                                                     .small(),
                                             )
                                             .into_any()
-                                })
+                                    }))
                             }),
                     ),
             )
@@ -280,6 +284,7 @@ impl Render for PopupStory {
                                         .w(px(300.)),
                                 )
                                 .content(|cx| {
+                                    cx.new_view(|cx|
                                         PopoverContent::new(cx, |cx| {
                                             v_flex()
                                                 .gap_4()
@@ -292,7 +297,7 @@ impl Render for PopupStory {
                                                         .small(),
                                                 )
                                                 .into_any()
-                                    })
+                                        }))
                                 }),
                         ),
                 ),

crates/ui/src/modal.rs

@@ -102,7 +102,7 @@ impl Modal {
     }
 
     /// Set the maximum width of the modal, defaults to `None`.
-    pub fn max_width(mut self, max_width: Pixels) -> Self {
+    pub fn max_w(mut self, max_width: Pixels) -> Self {
         self.max_width = Some(max_width);
         self
     }

crates/ui/src/popover.rs

@@ -16,21 +16,26 @@ pub fn init(_cx: &mut AppContext) {}
 pub struct PopoverContent {
     focus_handle: FocusHandle,
     content: Rc<dyn Fn(&mut WindowContext) -> AnyElement>,
+    max_width: Option<Pixels>,
 }
 
 impl PopoverContent {
-    pub fn new<B>(cx: &mut WindowContext, content: B) -> View<Self>
+    pub fn new<B>(cx: &mut WindowContext, content: B) -> Self
     where
         B: Fn(&mut WindowContext) -> AnyElement + 'static,
     {
-        cx.new_view(|cx| {
         let focus_handle = cx.focus_handle();
 
         Self {
             focus_handle,
             content: Rc::new(content),
+            max_width: None,
         }
-        })
+    }
+
+    pub fn max_w(mut self, max_width: Pixels) -> Self {
+        self.max_width = Some(max_width);
+        self
     }
 }
 impl EventEmitter<DismissEvent> for PopoverContent {}
@@ -43,7 +48,7 @@ impl FocusableView for PopoverContent {
 
 impl Render for PopoverContent {
     fn render(&mut self, cx: &mut ViewContext<Self>) -> impl IntoElement {
-        div().p_4().max_w_128().child(self.content.clone()(cx))
+        div().p_4().when_some(self.max_width, |this, v| this.max_w(v)).child(self.content.clone()(cx))
     }
 }
 
@@ -309,8 +314,8 @@ impl<M: ManagedView> Element for Popover<M> {
 
     fn paint(
         &mut self,
-        id: Option<&gpui::GlobalElementId>,
+        id: Option<&GlobalElementId>,
-        _bounds: gpui::Bounds<gpui::Pixels>,
+        _bounds: Bounds<Pixels>,
         request_layout: &mut Self::RequestLayoutState,
         prepaint: &mut Self::PrepaintState,
         cx: &mut WindowContext,

crates/ui/src/popup_menu.rs

@@ -113,8 +113,8 @@ impl PopupMenu {
     }
 
     /// Set max width of the popup menu, default is 500px
-    pub fn max_w(mut self, height: impl Into<Pixels>) -> Self {
+    pub fn max_w(mut self, width: impl Into<Pixels>) -> Self {
-        self.max_width = height.into();
+        self.max_width = width.into();
         self
     }