1// Copyright (c) 2012 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#ifndef UI_AURA_CLIENT_EVENT_CLIENT_H_
6#define UI_AURA_CLIENT_EVENT_CLIENT_H_
7
8#include "ui/aura/aura_export.h"
9
10namespace ui {
11class EventTarget;
12}
13
14namespace aura {
15class Window;
16namespace client {
17
18// An interface implemented by an object that alters event processing.
19class AURA_EXPORT EventClient {
20 public:
21  // Returns true if events can be processed by |window| or any of its children.
22  virtual bool CanProcessEventsWithinSubtree(const Window* window) const = 0;
23
24  // Returns the top level EventTarget for the current environment.
25  virtual ui::EventTarget* GetToplevelEventTarget() = 0;
26
27 protected:
28  virtual ~EventClient() {}
29};
30
31// Sets/Gets the event client on the root Window.
32AURA_EXPORT void SetEventClient(Window* root_window, EventClient* client);
33AURA_EXPORT EventClient* GetEventClient(const Window* root_window);
34
35}  // namespace clients
36}  // namespace aura
37
38#endif  // UI_AURA_CLIENT_EVENT_CLIENT_H_
39