ui/events/gestures/gesture_recognizer_impl.cc

   1 // Copyright (c) 2012 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_recognizer_impl.h"
   6
   7 #include <limits>
   8
   9 #include "base/command_line.h"
  10 #include "base/logging.h"
  11 #include "base/memory/scoped_ptr.h"
  12 #include "base/message_loop/message_loop.h"
  13 #include "base/time/time.h"
  14 #include "ui/events/event.h"
  15 #include "ui/events/event_constants.h"
  16 #include "ui/events/event_switches.h"
  17 #include "ui/events/event_utils.h"
  18 #include "ui/events/gesture_detection/gesture_configuration.h"
  19 #include "ui/events/gestures/gesture_types.h"
  20
  21 namespace ui {
  22
  23 namespace {
  24
  25 template <typename T>
  26 void TransferConsumer(GestureConsumer* current_consumer,
  27                       GestureConsumer* new_consumer,
  28                       std::map<GestureConsumer*, T>* map) {
  29   if (map->count(current_consumer)) {
  30     (*map)[new_consumer] = (*map)[current_consumer];
  31     map->erase(current_consumer);
  32   }
  33 }
  34
  35 bool RemoveConsumerFromMap(GestureConsumer* consumer,
  36                            GestureRecognizerImpl::TouchIdToConsumerMap* map) {
  37   bool consumer_removed = false;
  38   for (GestureRecognizerImpl::TouchIdToConsumerMap::iterator i = map->begin();
  39        i != map->end();) {
  40     if (i->second == consumer) {
  41       map->erase(i++);
  42       consumer_removed = true;
  43     } else {
  44       ++i;
  45     }
  46   }
  47   return consumer_removed;
  48 }
  49
  50 void TransferTouchIdToConsumerMap(
  51     GestureConsumer* old_consumer,
  52     GestureConsumer* new_consumer,
  53     GestureRecognizerImpl::TouchIdToConsumerMap* map) {
  54   for (GestureRecognizerImpl::TouchIdToConsumerMap::iterator i = map->begin();
  55        i != map->end(); ++i) {
  56     if (i->second == old_consumer)
  57       i->second = new_consumer;
  58   }
  59 }
  60
  61 GestureProviderAura* CreateGestureProvider(GestureProviderAuraClient* client) {
  62   return new GestureProviderAura(client);
  63 }
  64
  65 }  // namespace
  66
  67 ////////////////////////////////////////////////////////////////////////////////
  68 // GestureRecognizerImpl, public:
  69
  70 GestureRecognizerImpl::GestureRecognizerImpl() {
  71 }
  72
  73 GestureRecognizerImpl::~GestureRecognizerImpl() {
  74   STLDeleteValues(&consumer_gesture_provider_);
  75 }
  76
  77 // Checks if this finger is already down, if so, returns the current target.
  78 // Otherwise, returns NULL.
  79 GestureConsumer* GestureRecognizerImpl::GetTouchLockedTarget(
  80     const TouchEvent& event) {
  81   return touch_id_target_[event.touch_id()];
  82 }
  83
  84 GestureConsumer* GestureRecognizerImpl::GetTargetForGestureEvent(
  85     const GestureEvent& event) {
  86   int touch_id = event.details().oldest_touch_id();
  87   if (!touch_id_target_for_gestures_.count(touch_id)) {
  88     NOTREACHED() << "Touch ID does not map to a valid GestureConsumer.";
  89     return nullptr;
  90   }
  91
  92   return touch_id_target_for_gestures_.at(touch_id);
  93 }
  94
  95 GestureConsumer* GestureRecognizerImpl::GetTargetForLocation(
  96     const gfx::PointF& location, int source_device_id) {
  97   const float max_distance =
  98       GestureConfiguration::GetInstance()
  99           ->max_separation_for_gesture_touches_in_pixels();
 100
 101   gfx::PointF closest_point;
 102   int closest_touch_id = 0;
 103   double closest_distance_squared = std::numeric_limits<double>::infinity();
 104
 105   std::map<GestureConsumer*, GestureProviderAura*>::iterator i;
 106   for (i = consumer_gesture_provider_.begin();
 107        i != consumer_gesture_provider_.end();
 108        ++i) {
 109     const MotionEventAura& pointer_state = i->second->pointer_state();
 110     for (size_t j = 0; j < pointer_state.GetPointerCount(); ++j) {
 111       if (source_device_id != pointer_state.GetSourceDeviceId(j))
 112         continue;
 113       gfx::PointF point(pointer_state.GetX(j), pointer_state.GetY(j));
 114       // Relative distance is all we need here, so LengthSquared() is
 115       // appropriate, and cheaper than Length().
 116       double distance_squared = (point - location).LengthSquared();
 117       if (distance_squared < closest_distance_squared) {
 118         closest_point = point;
 119         closest_touch_id = pointer_state.GetPointerId(j);
 120         closest_distance_squared = distance_squared;
 121       }
 122     }
 123   }
 124
 125   if (closest_distance_squared < max_distance * max_distance)
 126     return touch_id_target_[closest_touch_id];
 127   return NULL;
 128 }
 129
 130 void GestureRecognizerImpl::CancelActiveTouchesExcept(
 131     GestureConsumer* not_cancelled) {
 132   for (const auto& consumer_provider : consumer_gesture_provider_) {
 133     if (consumer_provider.first == not_cancelled)
 134       continue;
 135     CancelActiveTouches(consumer_provider.first);
 136   }
 137 }
 138
 139 void GestureRecognizerImpl::TransferEventsTo(GestureConsumer* current_consumer,
 140                                              GestureConsumer* new_consumer) {
 141   DCHECK(current_consumer);
 142   DCHECK(new_consumer);
 143
 144   CancelActiveTouchesExcept(current_consumer);
 145
 146   TransferTouchIdToConsumerMap(current_consumer, new_consumer,
 147                                &touch_id_target_);
 148   TransferTouchIdToConsumerMap(current_consumer, new_consumer,
 149                                &touch_id_target_for_gestures_);
 150   TransferConsumer(current_consumer, new_consumer, &consumer_gesture_provider_);
 151 }
 152
 153 bool GestureRecognizerImpl::GetLastTouchPointForTarget(
 154     GestureConsumer* consumer,
 155     gfx::PointF* point) {
 156     if (consumer_gesture_provider_.count(consumer) == 0)
 157       return false;
 158     const MotionEvent& pointer_state =
 159         consumer_gesture_provider_[consumer]->pointer_state();
 160     *point = gfx::PointF(pointer_state.GetX(), pointer_state.GetY());
 161     return true;
 162 }
 163
 164 bool GestureRecognizerImpl::CancelActiveTouches(GestureConsumer* consumer) {
 165   bool cancelled_touch = false;
 166   if (consumer_gesture_provider_.count(consumer) == 0)
 167     return false;
 168   const MotionEventAura& pointer_state =
 169       consumer_gesture_provider_[consumer]->pointer_state();
 170   if (pointer_state.GetPointerCount() == 0)
 171     return false;
 172   // pointer_state is modified every time after DispatchCancelTouchEvent.
 173   scoped_ptr<MotionEvent> pointer_state_clone = pointer_state.Clone();
 174   for (size_t i = 0; i < pointer_state_clone->GetPointerCount(); ++i) {
 175     gfx::PointF point(pointer_state_clone->GetX(i),
 176                       pointer_state_clone->GetY(i));
 177     TouchEvent touch_event(ui::ET_TOUCH_CANCELLED,
 178                            point,
 179                            ui::EF_IS_SYNTHESIZED,
 180                            pointer_state_clone->GetPointerId(i),
 181                            ui::EventTimeForNow(),
 182                            0.0f,
 183                            0.0f,
 184                            0.0f,
 185                            0.0f);
 186     GestureEventHelper* helper = FindDispatchHelperForConsumer(consumer);
 187     if (helper)
 188       helper->DispatchCancelTouchEvent(&touch_event);
 189     cancelled_touch = true;
 190   }
 191   return cancelled_touch;
 192 }
 193
 194 ////////////////////////////////////////////////////////////////////////////////
 195 // GestureRecognizerImpl, private:
 196
 197 GestureProviderAura* GestureRecognizerImpl::GetGestureProviderForConsumer(
 198     GestureConsumer* consumer) {
 199   GestureProviderAura* gesture_provider = consumer_gesture_provider_[consumer];
 200   if (!gesture_provider) {
 201     gesture_provider = CreateGestureProvider(this);
 202     consumer_gesture_provider_[consumer] = gesture_provider;
 203   }
 204   return gesture_provider;
 205 }
 206
 207 void GestureRecognizerImpl::SetupTargets(const TouchEvent& event,
 208                                          GestureConsumer* target) {
 209   if (event.type() == ui::ET_TOUCH_RELEASED ||
 210       event.type() == ui::ET_TOUCH_CANCELLED) {
 211     touch_id_target_.erase(event.touch_id());
 212   } else if (event.type() == ui::ET_TOUCH_PRESSED) {
 213     touch_id_target_[event.touch_id()] = target;
 214     if (target)
 215       touch_id_target_for_gestures_[event.touch_id()] = target;
 216   }
 217 }
 218
 219 void GestureRecognizerImpl::DispatchGestureEvent(GestureEvent* event) {
 220   GestureConsumer* consumer = GetTargetForGestureEvent(*event);
 221   if (consumer) {
 222     GestureEventHelper* helper = FindDispatchHelperForConsumer(consumer);
 223     if (helper)
 224       helper->DispatchGestureEvent(event);
 225   }
 226 }
 227
 228 bool GestureRecognizerImpl::ProcessTouchEventPreDispatch(
 229     TouchEvent* event,
 230     GestureConsumer* consumer) {
 231   SetupTargets(*event, consumer);
 232
 233   if (event->result() & ER_CONSUMED)
 234     return false;
 235
 236   GestureProviderAura* gesture_provider =
 237       GetGestureProviderForConsumer(consumer);
 238   return gesture_provider->OnTouchEvent(event);
 239 }
 240
 241 GestureRecognizer::Gestures* GestureRecognizerImpl::AckTouchEvent(
 242     uint32 unique_event_id,
 243     ui::EventResult result,
 244     GestureConsumer* consumer) {
 245   GestureProviderAura* gesture_provider =
 246       GetGestureProviderForConsumer(consumer);
 247   gesture_provider->OnTouchEventAck(unique_event_id, result != ER_UNHANDLED);
 248   return gesture_provider->GetAndResetPendingGestures();
 249 }
 250
 251 bool GestureRecognizerImpl::CleanupStateForConsumer(
 252     GestureConsumer* consumer) {
 253   bool state_cleaned_up = false;
 254
 255   if (consumer_gesture_provider_.count(consumer)) {
 256     state_cleaned_up = true;
 257     delete consumer_gesture_provider_[consumer];
 258     consumer_gesture_provider_.erase(consumer);
 259   }
 260
 261   state_cleaned_up |= RemoveConsumerFromMap(consumer, &touch_id_target_);
 262   state_cleaned_up |=
 263       RemoveConsumerFromMap(consumer, &touch_id_target_for_gestures_);
 264   return state_cleaned_up;
 265 }
 266
 267 void GestureRecognizerImpl::AddGestureEventHelper(GestureEventHelper* helper) {
 268   helpers_.push_back(helper);
 269 }
 270
 271 void GestureRecognizerImpl::RemoveGestureEventHelper(
 272     GestureEventHelper* helper) {
 273   std::vector<GestureEventHelper*>::iterator it = std::find(helpers_.begin(),
 274       helpers_.end(), helper);
 275   if (it != helpers_.end())
 276     helpers_.erase(it);
 277 }
 278
 279 void GestureRecognizerImpl::OnGestureEvent(GestureEvent* event) {
 280   DispatchGestureEvent(event);
 281 }
 282
 283 GestureEventHelper* GestureRecognizerImpl::FindDispatchHelperForConsumer(
 284     GestureConsumer* consumer) {
 285   std::vector<GestureEventHelper*>::iterator it;
 286   for (it = helpers_.begin(); it != helpers_.end(); ++it) {
 287     if ((*it)->CanDispatchToConsumer(consumer))
 288       return (*it);
 289   }
 290   return NULL;
 291 }
 292
 293 // GestureRecognizer, static
 294 GestureRecognizer* GestureRecognizer::Create() {
 295   return new GestureRecognizerImpl();
 296 }
 297
 298 static GestureRecognizerImpl* g_gesture_recognizer_instance = NULL;
 299
 300 // GestureRecognizer, static
 301 GestureRecognizer* GestureRecognizer::Get() {
 302   if (!g_gesture_recognizer_instance)
 303     g_gesture_recognizer_instance = new GestureRecognizerImpl();
 304   return g_gesture_recognizer_instance;
 305 }
 306
 307 // GestureRecognizer, static
 308 void GestureRecognizer::Reset() {
 309   delete g_gesture_recognizer_instance;
 310   g_gesture_recognizer_instance = NULL;
 311 }
 312
 313 void SetGestureRecognizerForTesting(GestureRecognizer* gesture_recognizer) {
 314   // Transfer helpers to the new GR.
 315   std::vector<GestureEventHelper*>& helpers =
 316       g_gesture_recognizer_instance->helpers();
 317   std::vector<GestureEventHelper*>::iterator it;
 318   for (it = helpers.begin(); it != helpers.end(); ++it)
 319     gesture_recognizer->AddGestureEventHelper(*it);
 320
 321   helpers.clear();
 322   g_gesture_recognizer_instance =
 323       static_cast<GestureRecognizerImpl*>(gesture_recognizer);
 324 }
 325
 326 }  // namespace ui