Enable keyboard accelerators while a menu is open

ui/views/controls/menu/menu_message_loop_aura.cc

 // Copyright 2014 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_message_loop_aura.h"
 
 #if defined(OS_WIN)
 #include <windowsx.h>
 #endif
 
 #include "base/run_loop.h"
 #include "ui/aura/client/screen_position_client.h"
 #include "ui/aura/env.h"
 #include "ui/aura/window.h"
 #include "ui/aura/window_event_dispatcher.h"
 #include "ui/aura/window_tree_host.h"
 #include "ui/events/event.h"
 #include "ui/events/platform/platform_event_source.h"
 #include "ui/events/platform/scoped_event_dispatcher.h"
 #include "ui/views/controls/menu/menu_controller.h"
+#include "ui/views/controls/menu/menu_event_filter.h"
 #include "ui/views/widget/widget.h"
 #include "ui/wm/public/activation_change_observer.h"
 #include "ui/wm/public/activation_client.h"
 #include "ui/wm/public/dispatcher_client.h"
 #include "ui/wm/public/drag_drop_client.h"
 
 #if defined(OS_WIN)
 #include "ui/base/win/internal_constants.h"
 #include "ui/views/controls/menu/menu_message_pump_dispatcher_win.h"
 #include "ui/views/win/hwnd_util.h"
@@ skipping 65 matching lines @@
   DISALLOW_COPY_AND_ASSIGN(ActivationChangeObserverImpl);
 };
 
 }  // namespace
 
 // static
 MenuMessageLoop* MenuMessageLoop::Create() {
   return new MenuMessageLoopAura;
 }
 
-MenuMessageLoopAura::MenuMessageLoopAura() : owner_(NULL) {
+MenuMessageLoopAura::MenuMessageLoopAura() : owner_(nullptr) {
 }
 
 MenuMessageLoopAura::~MenuMessageLoopAura() {
 }
 
 void MenuMessageLoopAura::RepostEventToWindow(const ui::LocatedEvent& event,
                                               gfx::NativeWindow window,
                                               const gfx::Point& screen_loc) {
   aura::Window* root = window->GetRootWindow();
   ScreenPositionClient* spc = aura::client::GetScreenPositionClient(root);
@@ skipping 33 matching lines @@
     message_loop_quit_ = run_loop.QuitClosure();
     run_loop.Run();
   } else {
     base::MessageLoopForUI* loop = base::MessageLoopForUI::current();
     base::MessageLoop::ScopedNestableTaskAllower allow(loop);
     base::RunLoop run_loop(&nested_dispatcher);
     message_loop_quit_ = run_loop.QuitClosure();
     run_loop.Run();
   }
 #else
-  internal::MenuEventDispatcher event_dispatcher(controller);
-  scoped_ptr<ui::ScopedEventDispatcher> dispatcher_override;
-  if (ui::PlatformEventSource::GetInstance()) {
-    dispatcher_override =
-        ui::PlatformEventSource::GetInstance()->OverrideDispatcher(
-            &event_dispatcher);
-  }
+  scoped_ptr<ActivationChangeObserverImpl> observer;
   if (root) {
-    scoped_ptr<ActivationChangeObserverImpl> observer;
     if (!nested_menu)
       observer.reset(new ActivationChangeObserverImpl(controller, root));
-    aura::client::DispatcherRunLoop run_loop(
-        aura::client::GetDispatcherClient(root), NULL);
-    message_loop_quit_ = run_loop.QuitClosure();
-    run_loop.Run();
-  } else {
-    base::MessageLoopForUI* loop = base::MessageLoopForUI::current();
-    base::MessageLoop::ScopedNestableTaskAllower allow(loop);
-    base::RunLoop run_loop;
-    message_loop_quit_ = run_loop.QuitClosure();
-    run_loop.Run();
   }
-#endif
+
+  scoped_ptr<MenuEventFilter> menu_event_filter;
+  if (!nested_menu) {
+    // No need to recreate the MenuEventFilter for every nested menu.
+    menu_event_filter.reset(new MenuEventFilter);
+    aura::Env::GetInstanceDontCreate()->PrependPreTargetHandler(
+        menu_event_filter.get());

[oshima, 2015/09/08 21:43:08]

You can add/remove the filter in MenuEventFilter's ctor/dtor?

[afakhry, 2015/09/08 23:34:38]

Done.

+  }
+
+  base::MessageLoopForUI* loop = base::MessageLoopForUI::current();
+  base::MessageLoop::ScopedNestableTaskAllower allow(loop);
+  base::RunLoop run_loop;
+  message_loop_quit_ = run_loop.QuitClosure();
+
+  run_loop.Run();
+
+  if (menu_event_filter.get()) {
+    aura::Env::GetInstanceDontCreate()->RemovePreTargetHandler(
+        menu_event_filter.get());
+  }
+#endif  // defined(OS_WIN)
 }
 
 void MenuMessageLoopAura::QuitNow() {
   CHECK(!message_loop_quit_.is_null());
   message_loop_quit_.Run();
 
 #if !defined(OS_WIN)
   // Ask PlatformEventSource to stop dispatching events in this message loop
   // iteration. We want our menu's loop to return before the next event.
   if (ui::PlatformEventSource::GetInstance())
     ui::PlatformEventSource::GetInstance()->StopCurrentEventStream();
 #endif
 }
 
 void MenuMessageLoopAura::ClearOwner() {
   owner_ = NULL;
 }
 
 }  // namespace views