motion_event.h revision 5f1c94371a64b3196d4be9466099bb892df9b88e 
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  enum ToolType {
28    TOOL_TYPE_UNKNOWN,
29    TOOL_TYPE_FINGER,
30    TOOL_TYPE_STYLUS,
31    TOOL_TYPE_MOUSE,
32  };
33
34  enum ButtonType {
35    BUTTON_PRIMARY = 1 << 0,
36    BUTTON_SECONDARY = 1 << 1,
37    BUTTON_TERTIARY = 1 << 2,
38    BUTTON_BACK = 1 << 3,
39    BUTTON_FORWARD = 1 << 4,
40  };
41
42  // The implementer promises that |GetPointerId()| will never exceed this.
43  enum { MAX_POINTER_ID = 31 };
44
45  virtual ~MotionEvent() {}
46
47  virtual int GetId() const = 0;
48  virtual Action GetAction() const = 0;
49  // Only valid if |GetAction()| returns ACTION_POINTER_UP or
50  // ACTION_POINTER_DOWN.
51  virtual int GetActionIndex() const = 0;
52  virtual size_t GetPointerCount() const = 0;
53  virtual int GetPointerId(size_t pointer_index) const = 0;
54  virtual float GetX(size_t pointer_index) const = 0;
55  virtual float GetY(size_t pointer_index) const = 0;
56  virtual float GetRawX(size_t pointer_index) const = 0;
57  virtual float GetRawY(size_t pointer_index) const = 0;
58  virtual float GetTouchMajor(size_t pointer_index) const = 0;
59  virtual float GetPressure(size_t pointer_index) const = 0;
60  virtual ToolType GetToolType(size_t pointer_index) const = 0;
61  virtual int GetButtonState() const = 0;
62  virtual base::TimeTicks GetEventTime() const = 0;
63
64  // Optional historical data, default implementation provides an empty history.
65  virtual size_t GetHistorySize() const;
66  virtual base::TimeTicks GetHistoricalEventTime(size_t historical_index) const;
67  virtual float GetHistoricalTouchMajor(size_t pointer_index,
68                                        size_t historical_index) const;
69  virtual float GetHistoricalX(size_t pointer_index,
70                               size_t historical_index) const;
71  virtual float GetHistoricalY(size_t pointer_index,
72                               size_t historical_index) const;
73
74  virtual scoped_ptr<MotionEvent> Clone() const = 0;
75  virtual scoped_ptr<MotionEvent> Cancel() const = 0;
76
77  // Utility accessor methods for convenience.
78  float GetX() const { return GetX(0); }
79  float GetY() const { return GetY(0); }
80  float GetRawX() const { return GetRawX(0); }
81  float GetRawY() const { return GetRawY(0); }
82  float GetRawOffsetX() const { return GetRawX() - GetX(); }
83  float GetRawOffsetY() const { return GetRawY() - GetY(); }
84  float GetTouchMajor() const { return GetTouchMajor(0); }
85  float GetPressure() const { return GetPressure(0); }
86
87  // O(N) search of pointers (use sparingly!). Returns -1 if |id| nonexistent.
88  int FindPointerIndexOfId(int id) const;
89};
90
91GESTURE_DETECTION_EXPORT bool operator==(const MotionEvent& lhs,
92                                         const MotionEvent& rhs);
93GESTURE_DETECTION_EXPORT bool operator!=(const MotionEvent& lhs,
94                                         const MotionEvent& rhs);
95
96}  // namespace ui
97
98#endif  // UI_EVENTS_GESTURE_DETECTION_MOTION_EVENT_H_
99