ui/events/gesture_detection/gesture_event_data_packet.h

   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_GESTURE_EVENT_DATA_PACKET_H_
   6 #define UI_EVENTS_GESTURE_DETECTION_GESTURE_EVENT_DATA_PACKET_H_
   7
   8 #include "base/containers/stack_container.h"
   9 #include "ui/events/gesture_detection/gesture_detection_export.h"
  10 #include "ui/events/gesture_detection/gesture_event_data.h"
  11
  12 namespace ui {
  13
  14 class MotionEvent;
  15
  16 // Acts as a transport container for gestures created (directly or indirectly)
  17 // by a touch event.
  18 class GESTURE_DETECTION_EXPORT GestureEventDataPacket {
  19  public:
  20   enum GestureSource {
  21     UNDEFINED = -1,        // Used only for a default-constructed packet.
  22     INVALID,               // The source of the gesture was invalid.
  23     TOUCH_SEQUENCE_START,  // The start of a new gesture sequence.
  24     TOUCH_SEQUENCE_END,    // The end of a gesture sequence.
  25     TOUCH_SEQUENCE_CANCEL, // The gesture sequence was cancelled.
  26     TOUCH_START,           // A touch down occured during a gesture sequence.
  27     TOUCH_MOVE,            // A touch move occured during a gesture sequence.
  28     TOUCH_END,             // A touch up occured during a gesture sequence.
  29     TOUCH_TIMEOUT,         // Timeout from an existing gesture sequence.
  30   };
  31
  32   enum class AckState {
  33     PENDING,
  34     CONSUMED,
  35     UNCONSUMED,
  36   };
  37
  38   GestureEventDataPacket();
  39   GestureEventDataPacket(const GestureEventDataPacket& other);
  40   ~GestureEventDataPacket();
  41   GestureEventDataPacket& operator=(const GestureEventDataPacket& other);
  42
  43   // Factory methods for creating a packet from a particular event.
  44   static GestureEventDataPacket FromTouch(const ui::MotionEvent& touch);
  45   static GestureEventDataPacket FromTouchTimeout(
  46       const GestureEventData& gesture);
  47
  48   void Push(const GestureEventData& gesture);
  49
  50   const base::TimeTicks& timestamp() const { return timestamp_; }
  51   const GestureEventData& gesture(size_t i) const { return gestures_[i]; }
  52   size_t gesture_count() const { return gestures_->size(); }
  53   GestureSource gesture_source() const { return gesture_source_; }
  54   const gfx::PointF& touch_location() const { return touch_location_; }
  55   const gfx::PointF& raw_touch_location() const { return raw_touch_location_; }
  56
  57   // We store the ack with the packet until the packet reaches the
  58   // head of the queue, and then we handle the ack.
  59   void Ack(bool event_consumed);
  60   AckState ack_state() { return ack_state_; }
  61   uint32 unique_touch_event_id() const { return unique_touch_event_id_; }
  62
  63  private:
  64   GestureEventDataPacket(base::TimeTicks timestamp,
  65                          GestureSource source,
  66                          const gfx::PointF& touch_location,
  67                          const gfx::PointF& raw_touch_location,
  68                          uint32 unique_touch_event_id);
  69
  70   enum { kTypicalMaxGesturesPerTouch = 5 };
  71   base::TimeTicks timestamp_;
  72   base::StackVector<GestureEventData, kTypicalMaxGesturesPerTouch> gestures_;
  73   gfx::PointF touch_location_;
  74   gfx::PointF raw_touch_location_;
  75   GestureSource gesture_source_;
  76   AckState ack_state_;
  77   uint32 unique_touch_event_id_;
  78 };
  79
  80 }  // namespace ui
  81
  82 #endif  // UI_EVENTS_GESTURE_DETECTION_GESTURE_EVENT_DATA_PACKET_H_