Enable keyboard accelerators while a menu is open

ui/views/controls/menu/menu_event_filter.h

Index: ui/views/controls/menu/menu_event_filter.h
diff --git a/ui/views/controls/menu/menu_event_filter.h b/ui/views/controls/menu/menu_event_filter.h
new file mode 100644
index 0000000000000000000000000000000000000000..f7e621861be6d678f6e7220f50c5588c07154a2a
--- /dev/null
+++ b/ui/views/controls/menu/menu_event_filter.h
@@ -0,0 +1,73 @@
+// Copyright 2015 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.
+
+#ifndef UI_VIEWS_CONTROLS_MENU_MENU_EVENT_FILTER_H_
+#define UI_VIEWS_CONTROLS_MENU_MENU_EVENT_FILTER_H_
+
+#include "base/logging.h"
+#include "base/macros.h"
+#include "base/memory/scoped_ptr.h"
+#include "ui/events/event_handler.h"
+#include "ui/views/views_export.h"
+
+namespace aura {
+class Window;
+}
+
+namespace ui {
+class Accelerator;
+}
+
+namespace views {
+
+class MenuController;
+
+// Handles events while a menu is open.
+class VIEWS_EXPORT MenuEventFilter : public ui::EventHandler {
+ public:
+  // Defines a delegate interface for the MenuEventFilter that can handle
+  // accelerators on its behalf.
+  class Delegate {
+   public:
+    Delegate() {}
+    virtual ~Delegate() {}
+
+    // Stores |accelerator| in ui::AcceleratorHistory.
+    virtual void StoreInHistory(const ui::Accelerator& accelerator) = 0;
+
+    // Returns true if there is an action associated with |accelerator| and
+    // the menu should be closed before performing the action.
+    virtual bool ShouldCloseMenuAndRepostAccelerator(
+        const ui::Accelerator& accelerator) const = 0;
+
+    // Processes |accelerator| immediately.
+    virtual void ProcessAcceleratorNow(const ui::Accelerator& accelerator) = 0;
+  };
+
+  // |menu_controller| should be of the active MenuController, it can't be

[oshima, 2015/09/02 17:08:21]

If this should be one that is always active, why can't this use
MenuController::GetActiveInstance() instead of passing?

[afakhry, 2015/09/02 18:18:38]

Yes I used to do this in an earlier patch, but Peter suggested that we pass it
from MenuMessageLoopAura::Run() since we create and destroy the event filter
there. I can change this if you want?

[oshima, 2015/09/02 20:58:54]

which patch #?

[afakhry, 2015/09/03 16:41:42]

Patch #21: first comment on this file:
https://codereview.chromium.org/1138523006/diff/420001/ui/views/controls/menu...

+  // nullptr. If |delegate| is nullptr, the default delegate will be used.
+  MenuEventFilter(MenuController* menu_controller,
+                  MenuEventFilter::Delegate* delegate);
+  ~MenuEventFilter() override;
+
+  static void SetMenuEventFilterDelegate(aura::Window* root_window,
+                                         MenuEventFilter::Delegate* delegate);
+  static MenuEventFilter::Delegate* GetMenuEventFilterDelegate(
+      aura::Window* root_window);
+
+  // ui::EventHandler:
+  void OnKeyEvent(ui::KeyEvent* event) override;
+  void OnTouchEvent(ui::TouchEvent* event) override;
+
+ private:
+  MenuController* menu_controller_;  // Not owned.
+  scoped_ptr<MenuEventFilter::Delegate> default_delegate_;
+  MenuEventFilter::Delegate* filter_delegate_;  // Not owned.
+
+  DISALLOW_COPY_AND_ASSIGN(MenuEventFilter);
+};
+
+}  // namespace views
+
+#endif  // UI_VIEWS_CONTROLS_MENU_MENU_EVENT_FILTER_H_