MacViews: Intercept events for Menus (after AppKit has turned them into action messages).

ui/views/controls/menu/menu_controller.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/views/controls/menu/menu_controller.h"
 
 #include "base/i18n/case_conversion.h"
 #include "base/i18n/rtl.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/time/time.h"
@@ skipping 786 matching lines @@
 
 void MenuController::OnDragComplete(bool should_close) {
   DCHECK(drag_in_progress_);
   drag_in_progress_ = false;
   if (showing_ && should_close && GetActiveInstance() == this) {
     CloseAllNestedMenus();
     Cancel(EXIT_ALL);
   }
 }
 
+ui::PostDispatchAction MenuController::OnWillDispatchKeyEvent(
+    base::char16 character,
+    ui::KeyboardCode key_code) {
+  if (exit_type() == MenuController::EXIT_ALL ||
+      exit_type() == MenuController::EXIT_DESTROYED) {
+    TerminateNestedMessageLoop();
+    return ui::POST_DISPATCH_PERFORM_DEFAULT;
+  }
+
+  bool should_quit = character ? SelectByChar(character) : !OnKeyDown(key_code);
+  if (should_quit || exit_type() != MenuController::EXIT_NONE)
+    TerminateNestedMessageLoop();
+
+  return ui::POST_DISPATCH_NONE;
+}

[tapted, 2015/02/04 11:55:48]

This function started life being refactored out of
ui/views/controls/menu/menu_event_dispatcher_linux.cc's DispatchEvent() (see,
e.g., patchset 2). In the end, it had a fatal flaw in
`ui::GetCharacterFromKeyCode(..)` which doesn't handle unicode characters
properly (it's a test function really...). Then, after passing in the `unichar`
from the NSEvent I kept finding ways to simplify it, but the core logic is the
same.

+
 void MenuController::UpdateSubmenuSelection(SubmenuView* submenu) {
   if (submenu->IsShowing()) {
     gfx::Point point = GetScreen()->GetCursorScreenPoint();
     const SubmenuView* root_submenu =
         submenu->GetMenuItem()->GetRootMenuItem()->GetSubmenu();
     View::ConvertPointFromScreen(
         root_submenu->GetWidget()->GetRootView(), &point);
     HandleMouseLocation(submenu, point);
   }
 }
@@ skipping 204 matching lines @@
         OpenSubmenuChangeSelectionIfCan();
       break;
 
     case ui::VKEY_LEFT:
       if (base::i18n::IsRTL())
         OpenSubmenuChangeSelectionIfCan();
       else
         CloseSubmenu();
       break;
 
+// On Mac, treat space the same as return.
+#if !defined(OS_MACOSX)
     case ui::VKEY_SPACE:
       if (SendAcceleratorToHotTrackedView() == ACCELERATOR_PROCESSED_EXIT)
         return false;
       break;
+#endif
 
     case ui::VKEY_F4:
       if (!is_combobox_)
         break;
     // Fallthrough to accept or dismiss combobox menus on F4, like windows.
     case ui::VKEY_RETURN:
+#if defined(OS_MACOSX)
+    case ui::VKEY_SPACE:
+#endif
       if (pending_state_.item) {
         if (pending_state_.item->HasSubmenu()) {
           if (key_code == ui::VKEY_F4 &&
               pending_state_.item->GetSubmenu()->IsShowing())
             return false;
           else
             OpenSubmenuChangeSelectionIfCan();
         } else {
           SendAcceleratorResultType result = SendAcceleratorToHotTrackedView();
           if (result == ACCELERATOR_NOT_PROCESSED &&
@@ skipping 1255 matching lines @@
   }
 }
 
 gfx::Screen* MenuController::GetScreen() {
   Widget* root = owner_ ? owner_->GetTopLevelWidget() : NULL;
   return root ? gfx::Screen::GetScreenFor(root->GetNativeView())
               : gfx::Screen::GetNativeScreen();
 }
 
 }  // namespace views