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.
5 #ifndef UI_EVENTS_GESTURE_DETECTION_GESTURE_PROVIDER_H_
6 #define UI_EVENTS_GESTURE_DETECTION_GESTURE_PROVIDER_H_
8 #include "base/basictypes.h"
9 #include "base/memory/scoped_ptr.h"
10 #include "ui/events/gesture_detection/gesture_detection_export.h"
11 #include "ui/events/gesture_detection/gesture_detector.h"
12 #include "ui/events/gesture_detection/gesture_event_data.h"
13 #include "ui/events/gesture_detection/scale_gesture_detector.h"
14 #include "ui/events/gesture_detection/snap_scroll_controller.h"
15 #include "ui/gfx/display.h"
19 class GESTURE_DETECTION_EXPORT GestureProviderClient {
21 virtual ~GestureProviderClient() {}
22 virtual void OnGestureEvent(const GestureEventData& gesture) = 0;
25 // Given a stream of |MotionEvent|'s, provides gesture detection and gesture
27 class GESTURE_DETECTION_EXPORT GestureProvider {
29 struct GESTURE_DETECTION_EXPORT Config {
33 GestureDetector::Config gesture_detector_config;
34 ScaleGestureDetector::Config scale_gesture_detector_config;
36 // If |disable_click_delay| is true and double-tap support is disabled,
37 // there will be no delay before tap events. When double-tap support is
38 // enabled, there will always be a delay before a tap event is fired, in
39 // order to allow the double tap gesture to occur without firing any tap
41 bool disable_click_delay;
43 // If |gesture_begin_end_types_enabled| is true, fire an ET_GESTURE_BEGIN
44 // event for every added touch point, and an ET_GESTURE_END event for every
45 // removed touch point. This requires one ACTION_CANCEL event to be sent per
46 // touch point, which only occurs on Aura. Defaults to false.
47 bool gesture_begin_end_types_enabled;
49 // The min and max size (both length and width, in dips) of the generated
50 // bounding box for all gesture types. This is useful for touch streams
51 // that may report zero or unreasonably small or large touch sizes.
52 // Note that these bounds are only applied for touch or unknown tool types;
53 // mouse and stylus-derived gestures will not be affected.
54 // Both values default to 0 (disabled).
55 float min_gesture_bounds_length;
56 float max_gesture_bounds_length;
59 GestureProvider(const Config& config, GestureProviderClient* client);
62 // Handle the incoming MotionEvent, returning false if the event could not
64 bool OnTouchEvent(const MotionEvent& event);
66 // Update whether multi-touch pinch zoom is supported by the platform.
67 void SetMultiTouchZoomSupportEnabled(bool enabled);
69 // Update whether double-tap gestures are supported by the platform.
70 void SetDoubleTapSupportForPlatformEnabled(bool enabled);
72 // Update whether double-tap gesture detection should be suppressed, e.g.,
73 // if the page scale is fixed or the page has a mobile viewport. This disables
74 // the tap delay, allowing rapid and responsive single-tap gestures.
75 void SetDoubleTapSupportForPageEnabled(bool enabled);
77 // Whether a scroll gesture is in-progress.
78 bool IsScrollInProgress() const;
80 // Whether a pinch gesture is in-progress (i.e. a pinch update has been
81 // forwarded and detection is still active).
82 bool IsPinchInProgress() const;
84 // Whether a double-tap gesture is in-progress (either double-tap or
85 // double-tap drag zoom).
86 bool IsDoubleTapInProgress() const;
88 // May be NULL if there is no currently active touch sequence.
89 const ui::MotionEvent* current_down_event() const {
90 return current_down_event_.get();
94 void InitGestureDetectors(const Config& config);
96 bool CanHandle(const MotionEvent& event) const;
98 void Fling(const MotionEvent& e, float velocity_x, float velocity_y);
99 void Send(GestureEventData gesture);
100 bool SendLongTapIfNecessary(const MotionEvent& event);
101 void EndTouchScrollIfNecessary(const MotionEvent& event,
102 bool send_scroll_end_event);
103 void OnTouchEventHandlingBegin(const MotionEvent& event);
104 void OnTouchEventHandlingEnd(const MotionEvent& event);
105 void UpdateDoubleTapDetectionSupport();
107 GestureProviderClient* const client_;
109 class GestureListenerImpl;
110 friend class GestureListenerImpl;
111 scoped_ptr<GestureListenerImpl> gesture_listener_;
113 class ScaleGestureListenerImpl;
114 friend class ScaleGestureListenerImpl;
115 scoped_ptr<ScaleGestureListenerImpl> scale_gesture_listener_;
117 scoped_ptr<MotionEvent> current_down_event_;
119 // Whether the respective {SCROLL,PINCH}_BEGIN gestures have been terminated
120 // with a {SCROLL,PINCH}_END.
121 bool touch_scroll_in_progress_;
122 bool pinch_in_progress_;
124 // Whether double-tap gesture detection is currently supported.
125 bool double_tap_support_for_page_;
126 bool double_tap_support_for_platform_;
128 // Keeps track of the current GESTURE_LONG_PRESS event. If a context menu is
129 // opened after a GESTURE_LONG_PRESS, this is used to insert a
130 // GESTURE_TAP_CANCEL for removing any ::active styling.
131 base::TimeTicks current_longpress_time_;
133 const bool gesture_begin_end_types_enabled_;
135 const float min_gesture_bounds_length_;
136 const float max_gesture_bounds_length_;
141 #endif // UI_EVENTS_GESTURE_DETECTION_GESTURE_PROVIDER_H_