Bug 1705120 - Notify nsMenuX observers when a menu item is about to be activated, and supply the activated DOM element. r=harry

Differential Revision: https://phabricator.services.mozilla.com/D114434

widget/cocoa/NativeMenuMac.h

@@ -49,6 +49,8 @@ class NativeMenuMac : public NativeMenu,
   // nsMenuX::Observer
   void OnMenuWillOpen(mozilla::dom::Element* aPopupElement) override;
   void OnMenuDidOpen(mozilla::dom::Element* aPopupElement) override;
+  void OnMenuWillActivateItem(mozilla::dom::Element* aPopupElement,
+                              mozilla::dom::Element* aMenuItemElement) override;
   void OnMenuClosed(mozilla::dom::Element* aPopupElement) override;
 
   NSMenu* NativeNSMenu() { return mMenu ? mMenu->NativeNSMenu() : nil; }

widget/cocoa/NativeMenuMac.mm

@@ -192,6 +192,9 @@ void NativeMenuMac::OnMenuDidOpen(dom::Element* aPopupElement) {
   }
 }
 
+void NativeMenuMac::OnMenuWillActivateItem(mozilla::dom::Element* aPopupElement,
+                                           mozilla::dom::Element* aMenuItemElement) {}
+
 void NativeMenuMac::OnMenuClosed(dom::Element* aPopupElement) {
   // Our caller isn't keeping us alive, so make sure we stay alive throughout this function in case
   // one of the observer notifications destroys us.
@@ -309,14 +312,16 @@ void NativeMenuMac::ActivateItem(dom::Element* aItemElement, Modifiers aModifier
     aRv.ThrowInvalidStateError("Menu containing menu item is not open");
     return;
   }
-  Maybe<nsMenuX::MenuChild> item = menu->GetItemForElement(aItemElement);
-  if (!item || !item->is<RefPtr<nsMenuItemX>>()) {
+  Maybe<nsMenuX::MenuChild> child = menu->GetItemForElement(aItemElement);
+  if (!child || !child->is<RefPtr<nsMenuItemX>>()) {
     aRv.ThrowInvalidStateError("Could not find the supplied menu item");
     return;
   }
 
-  menu->ActivateItemAfterClosing(std::move(item->as<RefPtr<nsMenuItemX>>()),
-                                 ConvertModifierFlags(aModifiers), aButton);
+  RefPtr<nsMenuItemX> item = std::move(child->as<RefPtr<nsMenuItemX>>());
+  NSMenuItem* nativeItem = [item->NativeNSMenuItem() retain];
+
+  menu->ActivateItemAfterClosing(std::move(item), ConvertModifierFlags(aModifiers), aButton);
 
   // Notify the entire menu structure that the menu is closing in response to ActivateItem.
   mMenu->MenuClosed(true);
@@ -328,6 +333,13 @@ void NativeMenuMac::ActivateItem(dom::Element* aItemElement, Modifiers aModifier
   // handler, at least on macOS 11. However, the resulting MenuClosed call will not do anything
   // because we already called MenuClosed above.
   [mMenu->NativeNSMenu() cancelTrackingWithoutAnimation];
+
+  // Call OnWillActivateItem at the end, to match the order of calls that happen when a user
+  // activates a menu item in the real world: -[MenuDelegate menu:willActivateItem:] runs after
+  // menuDidClose.
+  menu->OnWillActivateItem(nativeItem);
+
+  [nativeItem release];
 }
 
 void NativeMenuMac::OpenSubmenu(dom::Element* aMenuElement) {

widget/cocoa/nsMenuX.h

@@ -47,6 +47,10 @@ class nsMenuXObserver {
   // No strong reference is held to the observer during the call.
   virtual void OnMenuDidOpen(mozilla::dom::Element* aPopupElement) = 0;
 
+  // Called before a menu item is activated.
+  virtual void OnMenuWillActivateItem(mozilla::dom::Element* aPopupElement,
+                                      mozilla::dom::Element* aMenuItemElement) = 0;
+
   // Called when a menu in this menu subtree closed, after popuphidden.
   // No strong reference is held to the observer during the call.
   virtual void OnMenuClosed(mozilla::dom::Element* aPopupElement) = 0;
@@ -79,6 +83,8 @@ class nsMenuX final : public nsMenuParentX,
   // nsMenuXObserver, to forward notifications from our children to our observer.
   void OnMenuWillOpen(mozilla::dom::Element* aPopupElement) override;
   void OnMenuDidOpen(mozilla::dom::Element* aPopupElement) override;
+  void OnMenuWillActivateItem(mozilla::dom::Element* aPopupElement,
+                              mozilla::dom::Element* aMenuItemElement) override;
   void OnMenuClosed(mozilla::dom::Element* aPopupElement) override;
 
   bool IsVisible() const { return mVisible; }
@@ -138,6 +144,10 @@ class nsMenuX final : public nsMenuParentX,
   // mNativeMenu.
   void OnHighlightedItemChanged(const mozilla::Maybe<uint32_t>& aNewHighlightedIndex);
 
+  // Called from the menu delegate before an item anywhere in this menu is activated.
+  // Called after MenuClosed().
+  void OnWillActivateItem(NSMenuItem* aItem);
+
   void SetRebuild(bool aMenuEvent);
   void SetupIcon();
   nsIContent* Content() { return mContent; }

widget/cocoa/nsMenuX.mm

@@ -189,6 +189,13 @@ void nsMenuX::OnMenuDidOpen(dom::Element* aPopupElement) {
   }
 }
 
+void nsMenuX::OnMenuWillActivateItem(dom::Element* aPopupElement, dom::Element* aMenuItemElement) {
+  RefPtr<nsMenuX> kungFuDeathGrip(this);
+  if (mObserver) {
+    mObserver->OnMenuWillActivateItem(aPopupElement, aMenuItemElement);
+  }
+}
+
 void nsMenuX::OnMenuClosed(dom::Element* aPopupElement) {
   RefPtr<nsMenuX> kungFuDeathGrip(this);
   if (mObserver) {
@@ -681,6 +688,22 @@ void nsMenuX::OnHighlightedItemChanged(const Maybe<uint32_t>& aNewHighlightedInd
   mHighlightedItemIndex = aNewHighlightedIndex;
 }
 
+void nsMenuX::OnWillActivateItem(NSMenuItem* aItem) {
+  if (!mIsOpenForGecko) {
+    return;
+  }
+
+  if (mMenuGroupOwner && mObserver) {
+    nsMenuItemX* item = mMenuGroupOwner->GetMenuItemForCommandID(uint32_t(aItem.tag));
+    if (item && item->Content()->IsElement()) {
+      RefPtr<dom::Element> itemElement = item->Content()->AsElement();
+      if (nsCOMPtr<nsIContent> popupContent = GetMenuPopupContent()) {
+        mObserver->OnMenuWillActivateItem(popupContent->AsElement(), itemElement);
+      }
+    }
+  }
+}
+
 void nsMenuX::RebuildMenu() {
   MOZ_RELEASE_ASSERT(mNeedsRebuild);
   gConstructingMenu = true;
@@ -1159,6 +1182,13 @@ void nsMenuX::Dump(uint32_t aIndent) const {
 
 // This is called after menuDidClose:.
 - (void)menu:(NSMenu*)aMenu willActivateItem:(NSMenuItem*)aItem {
+  if (!mGeckoMenu) {
+    return;
+  }
+
+  // Hold a strong reference to mGeckoMenu while calling its methods.
+  RefPtr<nsMenuX> geckoMenu = mGeckoMenu;
+  geckoMenu->OnWillActivateItem(aItem);
 }
 
 @end