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::TransferEventsTo(GestureConsumer* current_consumer,
 131                                              GestureConsumer* new_consumer) {
 132   // Send cancel to all those save |new_consumer| and |current_consumer|.
 133   // Don't send a cancel to |current_consumer|, unless |new_consumer| is NULL.
 134   // Dispatching a touch-cancel event can end up altering |touch_id_target_|
 135   // (e.g. when the target of the event is destroyed, causing it to be removed
 136   // from |touch_id_target_| in |CleanupStateForConsumer()|). So create a list
 137   // of the touch-ids that need to be cancelled, and dispatch the cancel events
 138   // for them at the end.
 139
 140   std::vector<GestureConsumer*> consumers;
 141   std::map<GestureConsumer*, GestureProviderAura*>::iterator i;
 142   for (i = consumer_gesture_provider_.begin();
 143        i != consumer_gesture_provider_.end();
 144        ++i) {
 145     if (i->first && i->first != new_consumer &&
 146         (i->first != current_consumer || new_consumer == NULL)) {
 147       consumers.push_back(i->first);
 148     }
 149   }
 150   for (std::vector<GestureConsumer*>::iterator iter = consumers.begin();
 151        iter != consumers.end();
 152        ++iter) {
 153     CancelActiveTouches(*iter);
 154   }
 155   // Transfer events from |current_consumer| to |new_consumer|.
 156   if (current_consumer && new_consumer) {
 157     TransferTouchIdToConsumerMap(current_consumer, new_consumer,
 158                                  &touch_id_target_);
 159     TransferTouchIdToConsumerMap(current_consumer, new_consumer,
 160                                  &touch_id_target_for_gestures_);
 161     TransferConsumer(
 162         current_consumer, new_consumer, &consumer_gesture_provider_);
 163   }
 164 }
 165
 166 bool GestureRecognizerImpl::GetLastTouchPointForTarget(
 167     GestureConsumer* consumer,
 168     gfx::PointF* point) {
 169     if (consumer_gesture_provider_.count(consumer) == 0)
 170       return false;
 171     const MotionEvent& pointer_state =
 172         consumer_gesture_provider_[consumer]->pointer_state();
 173     *point = gfx::PointF(pointer_state.GetX(), pointer_state.GetY());
 174     return true;
 175 }
 176
 177 bool GestureRecognizerImpl::CancelActiveTouches(GestureConsumer* consumer) {
 178   bool cancelled_touch = false;
 179   if (consumer_gesture_provider_.count(consumer) == 0)
 180     return false;
 181   const MotionEventAura& pointer_state =
 182       consumer_gesture_provider_[consumer]->pointer_state();
 183   if (pointer_state.GetPointerCount() == 0)
 184     return false;
 185   // Pointer_state is modified every time after DispatchCancelTouchEvent.
 186   scoped_ptr<MotionEvent> pointer_state_clone = pointer_state.Clone();
 187   for (size_t i = 0; i < pointer_state_clone->GetPointerCount(); ++i) {
 188     gfx::PointF point(pointer_state_clone->GetX(i),
 189                       pointer_state_clone->GetY(i));
 190     TouchEvent touch_event(ui::ET_TOUCH_CANCELLED,
 191                            point,
 192                            ui::EF_IS_SYNTHESIZED,
 193                            pointer_state_clone->GetPointerId(i),
 194                            ui::EventTimeForNow(),
 195                            0.0f,
 196                            0.0f,
 197                            0.0f,
 198                            0.0f);
 199     GestureEventHelper* helper = FindDispatchHelperForConsumer(consumer);
 200     if (helper)
 201       helper->DispatchCancelTouchEvent(&touch_event);
 202     cancelled_touch = true;
 203   }
 204   return cancelled_touch;
 205 }
 206
 207 ////////////////////////////////////////////////////////////////////////////////
 208 // GestureRecognizerImpl, private:
 209
 210 GestureProviderAura* GestureRecognizerImpl::GetGestureProviderForConsumer(
 211     GestureConsumer* consumer) {
 212   GestureProviderAura* gesture_provider = consumer_gesture_provider_[consumer];
 213   if (!gesture_provider) {
 214     gesture_provider = CreateGestureProvider(this);
 215     consumer_gesture_provider_[consumer] = gesture_provider;
 216   }
 217   return gesture_provider;
 218 }
 219
 220 void GestureRecognizerImpl::SetupTargets(const TouchEvent& event,
 221                                          GestureConsumer* target) {
 222   if (event.type() == ui::ET_TOUCH_RELEASED ||
 223       event.type() == ui::ET_TOUCH_CANCELLED) {
 224     touch_id_target_.erase(event.touch_id());
 225   } else if (event.type() == ui::ET_TOUCH_PRESSED) {
 226     touch_id_target_[event.touch_id()] = target;
 227     if (target)
 228       touch_id_target_for_gestures_[event.touch_id()] = target;
 229   }
 230 }
 231
 232 void GestureRecognizerImpl::DispatchGestureEvent(GestureEvent* event) {
 233   GestureConsumer* consumer = GetTargetForGestureEvent(*event);
 234   if (consumer) {
 235     GestureEventHelper* helper = FindDispatchHelperForConsumer(consumer);
 236     if (helper)
 237       helper->DispatchGestureEvent(event);
 238   }
 239 }
 240
 241 bool GestureRecognizerImpl::ProcessTouchEventPreDispatch(
 242     TouchEvent* event,
 243     GestureConsumer* consumer) {
 244   SetupTargets(*event, consumer);
 245
 246   if (event->result() & ER_CONSUMED)
 247     return false;
 248
 249   GestureProviderAura* gesture_provider =
 250       GetGestureProviderForConsumer(consumer);
 251   return gesture_provider->OnTouchEvent(event);
 252 }
 253
 254 // TODO(tdresser): we should take a unique_event_id here, and validate
 255 // that the correct event is being acked. See crbug.com/457669 for
 256 // details.
 257 GestureRecognizer::Gestures*
 258 GestureRecognizerImpl::AckAsyncTouchEvent(
 259     ui::EventResult result,
 260     GestureConsumer* consumer) {
 261   GestureProviderAura* gesture_provider =
 262       GetGestureProviderForConsumer(consumer);
 263   gesture_provider->OnAsyncTouchEventAck(result != ER_UNHANDLED);
 264   return gesture_provider->GetAndResetPendingGestures();
 265 }
 266
 267 GestureRecognizer::Gestures* GestureRecognizerImpl::AckSyncTouchEvent(
 268     const uint64 unique_event_id,
 269     ui::EventResult result,
 270     GestureConsumer* consumer) {
 271   GestureProviderAura* gesture_provider =
 272       GetGestureProviderForConsumer(consumer);
 273   gesture_provider->OnSyncTouchEventAck(unique_event_id,
 274                                         result != ER_UNHANDLED);
 275   return gesture_provider->GetAndResetPendingGestures();
 276 }
 277
 278 bool GestureRecognizerImpl::CleanupStateForConsumer(
 279     GestureConsumer* consumer) {
 280   bool state_cleaned_up = false;
 281
 282   if (consumer_gesture_provider_.count(consumer)) {
 283     state_cleaned_up = true;
 284     delete consumer_gesture_provider_[consumer];
 285     consumer_gesture_provider_.erase(consumer);
 286   }
 287
 288   state_cleaned_up |= RemoveConsumerFromMap(consumer, &touch_id_target_);
 289   state_cleaned_up |=
 290       RemoveConsumerFromMap(consumer, &touch_id_target_for_gestures_);
 291   return state_cleaned_up;
 292 }
 293
 294 void GestureRecognizerImpl::AddGestureEventHelper(GestureEventHelper* helper) {
 295   helpers_.push_back(helper);
 296 }
 297
 298 void GestureRecognizerImpl::RemoveGestureEventHelper(
 299     GestureEventHelper* helper) {
 300   std::vector<GestureEventHelper*>::iterator it = std::find(helpers_.begin(),
 301       helpers_.end(), helper);
 302   if (it != helpers_.end())
 303     helpers_.erase(it);
 304 }
 305
 306 void GestureRecognizerImpl::OnGestureEvent(GestureEvent* event) {
 307   DispatchGestureEvent(event);
 308 }
 309
 310 GestureEventHelper* GestureRecognizerImpl::FindDispatchHelperForConsumer(
 311     GestureConsumer* consumer) {
 312   std::vector<GestureEventHelper*>::iterator it;
 313   for (it = helpers_.begin(); it != helpers_.end(); ++it) {
 314     if ((*it)->CanDispatchToConsumer(consumer))
 315       return (*it);
 316   }
 317   return NULL;
 318 }
 319
 320 // GestureRecognizer, static
 321 GestureRecognizer* GestureRecognizer::Create() {
 322   return new GestureRecognizerImpl();
 323 }
 324
 325 static GestureRecognizerImpl* g_gesture_recognizer_instance = NULL;
 326
 327 // GestureRecognizer, static
 328 GestureRecognizer* GestureRecognizer::Get() {
 329   if (!g_gesture_recognizer_instance)
 330     g_gesture_recognizer_instance = new GestureRecognizerImpl();
 331   return g_gesture_recognizer_instance;
 332 }
 333
 334 // GestureRecognizer, static
 335 void GestureRecognizer::Reset() {
 336   delete g_gesture_recognizer_instance;
 337   g_gesture_recognizer_instance = NULL;
 338 }
 339
 340 void SetGestureRecognizerForTesting(GestureRecognizer* gesture_recognizer) {
 341   // Transfer helpers to the new GR.
 342   std::vector<GestureEventHelper*>& helpers =
 343       g_gesture_recognizer_instance->helpers();
 344   std::vector<GestureEventHelper*>::iterator it;
 345   for (it = helpers.begin(); it != helpers.end(); ++it)
 346     gesture_recognizer->AddGestureEventHelper(*it);
 347
 348   helpers.clear();
 349   g_gesture_recognizer_instance =
 350       static_cast<GestureRecognizerImpl*>(gesture_recognizer);
 351 }
 352
 353 }  // namespace ui