event_processor.h revision a3f6a49ab37290eeeb8db0f41ec0f1cb74a68be7 
1// Copyright 2013 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_EVENTS_EVENT_PROCESSOR_H_
6#define UI_EVENTS_EVENT_PROCESSOR_H_
7
8#include "ui/events/event_dispatcher.h"
9#include "ui/events/event_source.h"
10
11namespace ui {
12
13// EventProcessor receives an event from an EventSource and dispatches it to a
14// tree of EventTargets.
15class EVENTS_EXPORT EventProcessor : public EventDispatcherDelegate {
16 public:
17  virtual ~EventProcessor() {}
18
19  // Returns the root of the tree this event processor owns.
20  virtual EventTarget* GetRootTarget() = 0;
21
22  // Dispatches an event received from the EventSource to the tree of
23  // EventTargets (whose root is returned by GetRootTarget()).
24  virtual EventDispatchDetails OnEventFromSource(Event* event)
25      WARN_UNUSED_RESULT;
26};
27
28}  // namespace ui
29
30#endif  // UI_EVENTS_EVENT_PROCESSOR_H_
31