motion_event.h revision 6d86b77056ed63eb6871182f42a9fd5f07550f90 
1// Copyright 2014 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_GESTURE_DETECTION_MOTION_EVENT_H_
6#define UI_EVENTS_GESTURE_DETECTION_MOTION_EVENT_H_
7
8#include "base/memory/scoped_ptr.h"
9#include "base/time/time.h"
10#include "ui/events/gesture_detection/gesture_detection_export.h"
11
12namespace ui {
13
14// Abstract class for a generic motion-related event, patterned after that
15// subset of Android's MotionEvent API used in gesture detection.
16class GESTURE_DETECTION_EXPORT MotionEvent {
17 public:
18  enum Action {
19    ACTION_DOWN,
20    ACTION_UP,
21    ACTION_MOVE,
22    ACTION_CANCEL,
23    ACTION_POINTER_DOWN,
24    ACTION_POINTER_UP,
25  };
26
27  // The implementer promises that |GetPointerId()| will never exceed this.
28  enum { MAX_POINTER_ID = 31 };
29
30  virtual ~MotionEvent() {}
31
32  virtual int GetId() const = 0;
33  virtual Action GetAction() const = 0;
34  // Only valid if |GetAction()| returns ACTION_POINTER_UP or
35  // ACTION_POINTER_DOWN.
36  virtual int GetActionIndex() const = 0;
37  virtual size_t GetPointerCount() const = 0;
38  virtual int GetPointerId(size_t pointer_index) const = 0;
39  virtual float GetX(size_t pointer_index) const = 0;
40  virtual float GetY(size_t pointer_index) const = 0;
41  virtual float GetRawX(size_t pointer_index) const = 0;
42  virtual float GetRawY(size_t pointer_index) const = 0;
43  virtual float GetTouchMajor(size_t pointer_index) const = 0;
44  virtual float GetPressure(size_t pointer_index) const = 0;
45  virtual base::TimeTicks GetEventTime() const = 0;
46
47  virtual size_t GetHistorySize() const = 0;
48  virtual base::TimeTicks GetHistoricalEventTime(
49      size_t historical_index) const = 0;
50  virtual float GetHistoricalTouchMajor(size_t pointer_index,
51                                        size_t historical_index) const = 0;
52  virtual float GetHistoricalX(size_t pointer_index,
53                               size_t historical_index) const = 0;
54  virtual float GetHistoricalY(size_t pointer_index,
55                               size_t historical_index) const = 0;
56
57  virtual scoped_ptr<MotionEvent> Clone() const = 0;
58  virtual scoped_ptr<MotionEvent> Cancel() const = 0;
59
60  // Utility accessor methods for convenience.
61  float GetX() const { return GetX(0); }
62  float GetY() const { return GetY(0); }
63  float GetRawX() const { return GetRawX(0); }
64  float GetRawY() const { return GetRawY(0); }
65  float GetRawOffsetX() const { return GetRawX() - GetX(); }
66  float GetRawOffsetY() const { return GetRawY() - GetY(); }
67  float GetTouchMajor() const { return GetTouchMajor(0); }
68  float GetPressure() const { return GetPressure(0); }
69};
70
71}  // namespace ui
72
73#endif  // UI_EVENTS_GESTURE_DETECTION_MOTION_EVENT_H_
74