fix(windows): attach subclass for context menu if window doesn't have a menu bar (#105)

.changes/windows-context-menu.md

@@ -0,0 +1,5 @@
+---
+"muda": "patch"
+---
+
+On Windows, fix menu items inside a context menu not firing events if the context menu was used on a Window that doesn't have a menu bar.

src/items/submenu.rs

@@ -207,12 +207,12 @@ impl ContextMenu for Submenu {
 
     #[cfg(target_os = "windows")]
     fn attach_menu_subclass_for_hwnd(&self, hwnd: isize) {
-        self.inner.borrow_mut().attach_menu_subclass_for_hwnd(hwnd)
+        self.inner.borrow().attach_menu_subclass_for_hwnd(hwnd)
     }
 
     #[cfg(target_os = "windows")]
     fn detach_menu_subclass_from_hwnd(&self, hwnd: isize) {
-        self.inner.borrow_mut().detach_menu_subclass_from_hwnd(hwnd)
+        self.inner.borrow().detach_menu_subclass_from_hwnd(hwnd)
     }
 
     #[cfg(target_os = "linux")]

src/menu.rs

@@ -324,7 +324,7 @@ impl ContextMenu for Menu {
     #[cfg(target_os = "windows")]
     fn show_context_menu_for_hwnd(&self, hwnd: isize, position: Option<Position>) {
         self.inner
-            .borrow()
+            .borrow_mut()
             .show_context_menu_for_hwnd(hwnd, position)
     }
 

src/platform_impl/windows/mod.rs

@@ -34,11 +34,11 @@ use windows_sys::Win32::{
             AppendMenuW, CreateAcceleratorTableW, CreateMenu, CreatePopupMenu,
             DestroyAcceleratorTable, DestroyMenu, DrawMenuBar, EnableMenuItem, GetCursorPos,
             GetMenu, GetMenuItemInfoW, InsertMenuW, PostQuitMessage, RemoveMenu, SendMessageW,
-            SetMenu, SetMenuItemInfoW, ShowWindow, TrackPopupMenu, HACCEL, HMENU, MENUITEMINFOW,
+            SetForegroundWindow, SetMenu, SetMenuItemInfoW, ShowWindow, TrackPopupMenu, HACCEL,
-            MFS_CHECKED, MFS_DISABLED, MF_BYCOMMAND, MF_BYPOSITION, MF_CHECKED, MF_DISABLED,
+            HMENU, MENUITEMINFOW, MFS_CHECKED, MFS_DISABLED, MF_BYCOMMAND, MF_BYPOSITION,
-            MF_ENABLED, MF_GRAYED, MF_POPUP, MF_SEPARATOR, MF_STRING, MF_UNCHECKED, MIIM_BITMAP,
+            MF_CHECKED, MF_DISABLED, MF_ENABLED, MF_GRAYED, MF_POPUP, MF_SEPARATOR, MF_STRING,
-            MIIM_STATE, MIIM_STRING, SW_HIDE, SW_MAXIMIZE, SW_MINIMIZE, TPM_LEFTALIGN, WM_CLOSE,
+            MF_UNCHECKED, MIIM_BITMAP, MIIM_STATE, MIIM_STRING, SW_HIDE, SW_MAXIMIZE, SW_MINIMIZE,
-            WM_COMMAND,
+            TPM_LEFTALIGN, WM_CLOSE, WM_COMMAND,
         },
     },
 };
@@ -100,6 +100,7 @@ pub(crate) struct Menu {
     hmenu: HMENU,
     hpopupmenu: HMENU,
     hwnds: Vec<HWND>,
+    context_hwnds: Vec<HWND>,
     haccel_store: Rc<RefCell<AccelWrapper>>,
     children: Vec<Rc<RefCell<MenuChild>>>,
 }
@@ -136,6 +137,14 @@ impl Drop for Menu {
         }
 
         unsafe {
+            for hwnd in &self.hwnds {
+                SetMenu(*hwnd, 0);
+                RemoveWindowSubclass(*hwnd, Some(menu_subclass_proc), MENU_SUBCLASS_ID);
+            }
+            for hwnd in &self.context_hwnds {
+                SetMenu(*hwnd, 0);
+                RemoveWindowSubclass(*hwnd, Some(menu_subclass_proc), MENU_SUBCLASS_ID);
+            }
             DestroyMenu(self.hmenu);
             DestroyMenu(self.hpopupmenu);
         }
@@ -153,6 +162,7 @@ impl Menu {
             haccel_store: Rc::new(RefCell::new((0, HashMap::new()))),
             children: Vec::new(),
             hwnds: Vec::new(),
+            context_hwnds: Vec::new(),
         }
     }
 
@@ -320,12 +330,14 @@ impl Menu {
         self.hwnds.push(hwnd);
         unsafe {
             SetMenu(hwnd, self.hmenu);
-            SetWindowSubclass(
+            if !self.context_hwnds.iter().any(|h| *h == hwnd) {
-                hwnd,
+                SetWindowSubclass(
-                Some(menu_subclass_proc),
+                    hwnd,
-                MENU_SUBCLASS_ID,
+                    Some(menu_subclass_proc),
-                Box::into_raw(Box::new(self)) as _,
+                    MENU_SUBCLASS_ID,
-            );
+                    Box::into_raw(Box::new(self)) as _,
+                );
+            }
             DrawMenuBar(hwnd);
         };
 
@@ -340,7 +352,9 @@ impl Menu {
             .ok_or(crate::Error::NotInitialized)?;
         self.hwnds.remove(index);
         unsafe {
-            RemoveWindowSubclass(hwnd, Some(menu_subclass_proc), MENU_SUBCLASS_ID);
+            if !self.context_hwnds.iter().any(|h| *h == hwnd) {
+                RemoveWindowSubclass(hwnd, Some(menu_subclass_proc), MENU_SUBCLASS_ID);
+            }
             SetMenu(hwnd, 0);
             DrawMenuBar(hwnd);
         }
@@ -399,8 +413,21 @@ impl Menu {
             .unwrap_or(false)
     }
 
-    pub fn show_context_menu_for_hwnd(&self, hwnd: isize, position: Option<Position>) {
+    pub fn show_context_menu_for_hwnd(&mut self, hwnd: isize, position: Option<Position>) {
-        show_context_menu(hwnd, self.hpopupmenu, position)
+        let hpopupmenu = self.hpopupmenu;
+        if !self.context_hwnds.iter().any(|h| *h == hwnd) && !self.hwnds.iter().any(|h| *h == hwnd)
+        {
+            self.context_hwnds.push(hwnd);
+            unsafe {
+                SetWindowSubclass(
+                    hwnd,
+                    Some(menu_subclass_proc),
+                    MENU_SUBCLASS_ID,
+                    Box::into_raw(Box::new(self)) as _,
+                );
+            }
+        }
+        show_context_menu(hwnd, hpopupmenu, position)
     }
 }
 
@@ -432,11 +459,19 @@ pub(crate) struct MenuChild {
     hmenu: HMENU,
     hpopupmenu: HMENU,
     pub children: Option<Vec<Rc<RefCell<MenuChild>>>>,
+    context_hwnds: Option<Vec<HWND>>,
 }
 
 impl Drop for MenuChild {
     fn drop(&mut self) {
         if self.item_type == MenuItemType::Submenu {
+            for hwnd in self.context_hwnds.as_ref().unwrap() {
+                unsafe {
+                    SetMenu(*hwnd, 0);
+                    RemoveWindowSubclass(*hwnd, Some(menu_subclass_proc), SUBMENU_SUBCLASS_ID);
+                }
+            }
+
             unsafe {
                 DestroyMenu(self.hmenu);
                 DestroyMenu(self.hpopupmenu);
@@ -475,6 +510,7 @@ impl MenuChild {
             children: None,
             hmenu: 0,
             hpopupmenu: 0,
+            context_hwnds: None,
         }
     }
 
@@ -495,6 +531,7 @@ impl MenuChild {
             icon: None,
             checked: false,
             accelerator: None,
+            context_hwnds: Some(Vec::new()),
         }
     }
 
@@ -515,6 +552,7 @@ impl MenuChild {
             children: None,
             hmenu: 0,
             hpopupmenu: 0,
+            context_hwnds: None,
         }
     }
 
@@ -541,6 +579,7 @@ impl MenuChild {
             children: None,
             hmenu: 0,
             hpopupmenu: 0,
+            context_hwnds: None,
         }
     }
 
@@ -567,6 +606,7 @@ impl MenuChild {
             children: None,
             hmenu: 0,
             hpopupmenu: 0,
+            context_hwnds: None,
         }
     }
 
@@ -593,6 +633,7 @@ impl MenuChild {
             children: None,
             hmenu: 0,
             hpopupmenu: 0,
+            context_hwnds: None,
         }
     }
 }
@@ -889,8 +930,26 @@ impl MenuChild {
             .collect()
     }
 
-    pub fn show_context_menu_for_hwnd(&self, hwnd: isize, position: Option<Position>) {
+    pub fn show_context_menu_for_hwnd(&mut self, hwnd: isize, position: Option<Position>) {
-        show_context_menu(hwnd, self.hpopupmenu, position)
+        let hpopupmenu = self.hpopupmenu;
+        unsafe {
+            if !self
+                .context_hwnds
+                .as_ref()
+                .unwrap()
+                .iter()
+                .any(|h| *h == hwnd)
+            {
+                self.context_hwnds.as_mut().unwrap().push(hwnd);
+                SetWindowSubclass(
+                    hwnd,
+                    Some(menu_subclass_proc),
+                    SUBMENU_SUBCLASS_ID,
+                    Box::into_raw(Box::new(self)) as _,
+                );
+            }
+        }
+        show_context_menu(hwnd, hpopupmenu, position)
     }
 
     pub fn attach_menu_subclass_for_hwnd(&self, hwnd: isize) {
@@ -952,6 +1011,7 @@ fn show_context_menu(hwnd: HWND, hmenu: HMENU, position: Option<Position>) {
             GetCursorPos(&mut pt);
             pt
         };
+        SetForegroundWindow(hwnd);
         TrackPopupMenu(hmenu, TPM_LEFTALIGN, pt.x, pt.y, 0, hwnd, std::ptr::null());
     }
 }