src/ui/events/gestures/gesture_provider_aura.cc

   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 #include "ui/events/gestures/gesture_provider_aura.h"
   6
   7 #include "base/auto_reset.h"
   8 #include "base/logging.h"
   9 #include "ui/events/event.h"
  10 #include "ui/events/gesture_detection/gesture_config_helper.h"
  11 #include "ui/events/gesture_detection/gesture_event_data.h"
  12 #include "ui/events/gestures/gesture_configuration.h"
  13
  14 namespace ui {
  15
  16 GestureProviderAura::GestureProviderAura(GestureProviderAuraClient* client)
  17     : client_(client),
  18       filtered_gesture_provider_(ui::DefaultGestureProviderConfig(), this),
  19       handling_event_(false) {
  20   filtered_gesture_provider_.SetDoubleTapSupportForPlatformEnabled(false);
  21 }
  22
  23 GestureProviderAura::~GestureProviderAura() {}
  24
  25 bool GestureProviderAura::OnTouchEvent(const TouchEvent& event) {
  26   int index = pointer_state_.FindPointerIndexOfId(event.touch_id());
  27   bool pointer_id_is_active = index != -1;
  28
  29   if (event.type() == ET_TOUCH_PRESSED && pointer_id_is_active) {
  30     // Ignore touch press events if we already believe the pointer is down.
  31     return false;
  32   } else if (event.type() != ET_TOUCH_PRESSED && !pointer_id_is_active) {
  33     // We could have an active touch stream transfered to us, resulting in touch
  34     // move or touch up events without associated touch down events. Ignore
  35     // them.
  36     return false;
  37   }
  38
  39   // If this is a touchmove event, and it isn't different from the last
  40   // event, ignore it.
  41   if (event.type() == ET_TOUCH_MOVED &&
  42       event.x() == pointer_state_.GetX(index) &&
  43       event.y() == pointer_state_.GetY(index)) {
  44     return false;
  45   }
  46
  47   last_touch_event_latency_info_ = *event.latency();
  48   pointer_state_.OnTouch(event);
  49
  50   bool result = filtered_gesture_provider_.OnTouchEvent(pointer_state_);
  51   pointer_state_.CleanupRemovedTouchPoints(event);
  52   return result;
  53 }
  54
  55 void GestureProviderAura::OnTouchEventAck(bool event_consumed) {
  56   DCHECK(pending_gestures_.empty());
  57   DCHECK(!handling_event_);
  58   base::AutoReset<bool> handling_event(&handling_event_, true);
  59   filtered_gesture_provider_.OnTouchEventAck(event_consumed);
  60   last_touch_event_latency_info_.Clear();
  61 }
  62
  63 void GestureProviderAura::OnGestureEvent(
  64     const GestureEventData& gesture) {
  65   GestureEventDetails details = gesture.details;
  66   details.set_oldest_touch_id(gesture.motion_event_id);
  67
  68   if (gesture.type() == ET_GESTURE_TAP) {
  69     int tap_count = 1;
  70     if (previous_tap_ && IsConsideredDoubleTap(*previous_tap_, gesture))
  71       tap_count = 1 + (previous_tap_->details.tap_count() % 3);
  72     details.set_tap_count(tap_count);
  73     if (!previous_tap_)
  74       previous_tap_.reset(new GestureEventData(gesture));
  75     else
  76       *previous_tap_ = gesture;
  77     previous_tap_->details = details;
  78   } else if (gesture.type() == ET_GESTURE_TAP_CANCEL) {
  79     previous_tap_.reset();
  80   }
  81
  82   scoped_ptr<ui::GestureEvent> event(
  83       new ui::GestureEvent(gesture.x,
  84                            gesture.y,
  85                            gesture.flags,
  86                            gesture.time - base::TimeTicks(),
  87                            details));
  88
  89   ui::LatencyInfo* gesture_latency = event->latency();
  90
  91   gesture_latency->CopyLatencyFrom(
  92       last_touch_event_latency_info_,
  93       ui::INPUT_EVENT_LATENCY_ORIGINAL_COMPONENT);
  94   gesture_latency->CopyLatencyFrom(
  95       last_touch_event_latency_info_,
  96       ui::INPUT_EVENT_LATENCY_UI_COMPONENT);
  97   gesture_latency->CopyLatencyFrom(
  98       last_touch_event_latency_info_,
  99       ui::INPUT_EVENT_LATENCY_ACKED_TOUCH_COMPONENT);
 100
 101   if (!handling_event_) {
 102     // Dispatching event caused by timer.
 103     client_->OnGestureEvent(event.get());
 104   } else {
 105     // Memory managed by ScopedVector pending_gestures_.
 106     pending_gestures_.push_back(event.release());
 107   }
 108 }
 109
 110 ScopedVector<GestureEvent>* GestureProviderAura::GetAndResetPendingGestures() {
 111   if (pending_gestures_.empty())
 112     return NULL;
 113   // Caller is responsible for deleting old_pending_gestures.
 114   ScopedVector<GestureEvent>* old_pending_gestures =
 115       new ScopedVector<GestureEvent>();
 116   old_pending_gestures->swap(pending_gestures_);
 117   return old_pending_gestures;
 118 }
 119
 120 bool GestureProviderAura::IsConsideredDoubleTap(
 121     const GestureEventData& previous_tap,
 122     const GestureEventData& current_tap) const {
 123   if (current_tap.time - previous_tap.time >
 124       base::TimeDelta::FromMilliseconds(
 125           ui::GestureConfiguration::max_seconds_between_double_click() *
 126           1000)) {
 127     return false;
 128   }
 129
 130   double double_tap_slop_square =
 131       GestureConfiguration::max_distance_between_taps_for_double_tap();
 132   double_tap_slop_square *= double_tap_slop_square;
 133   const float delta_x = previous_tap.x - current_tap.x;
 134   const float delta_y = previous_tap.y - current_tap.y;
 135   return (delta_x * delta_x + delta_y * delta_y < double_tap_slop_square);
 136 }
 137
 138 }  // namespace content