ui/aura/window_event_dispatcher.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/aura/window_event_dispatcher.h"
   6
   7 #include "base/bind.h"
   8 #include "base/debug/trace_event.h"
   9 #include "base/logging.h"
  10 #include "base/message_loop/message_loop.h"
  11 #include "ui/aura/client/capture_client.h"
  12 #include "ui/aura/client/cursor_client.h"
  13 #include "ui/aura/client/event_client.h"
  14 #include "ui/aura/client/focus_client.h"
  15 #include "ui/aura/client/screen_position_client.h"
  16 #include "ui/aura/env.h"
  17 #include "ui/aura/window.h"
  18 #include "ui/aura/window_delegate.h"
  19 #include "ui/aura/window_targeter.h"
  20 #include "ui/aura/window_tracker.h"
  21 #include "ui/aura/window_tree_host.h"
  22 #include "ui/base/hit_test.h"
  23 #include "ui/compositor/dip_util.h"
  24 #include "ui/events/event.h"
  25 #include "ui/events/gestures/gesture_recognizer.h"
  26 #include "ui/events/gestures/gesture_types.h"
  27
  28 typedef ui::EventDispatchDetails DispatchDetails;
  29
  30 namespace aura {
  31
  32 namespace {
  33
  34 // Returns true if |target| has a non-client (frame) component at |location|,
  35 // in window coordinates.
  36 bool IsNonClientLocation(Window* target, const gfx::Point& location) {
  37   if (!target->delegate())
  38     return false;
  39   int hit_test_code = target->delegate()->GetNonClientComponent(location);
  40   return hit_test_code != HTCLIENT && hit_test_code != HTNOWHERE;
  41 }
  42
  43 Window* ConsumerToWindow(ui::GestureConsumer* consumer) {
  44   return consumer ? static_cast<Window*>(consumer) : NULL;
  45 }
  46
  47 void SetLastMouseLocation(const Window* root_window,
  48                           const gfx::Point& location_in_root) {
  49   client::ScreenPositionClient* client =
  50       client::GetScreenPositionClient(root_window);
  51   if (client) {
  52     gfx::Point location_in_screen = location_in_root;
  53     client->ConvertPointToScreen(root_window, &location_in_screen);
  54     Env::GetInstance()->set_last_mouse_location(location_in_screen);
  55   } else {
  56     Env::GetInstance()->set_last_mouse_location(location_in_root);
  57   }
  58 }
  59
  60 bool IsEventCandidateForHold(const ui::Event& event) {
  61   if (event.type() == ui::ET_TOUCH_MOVED)
  62     return true;
  63   if (event.type() == ui::ET_MOUSE_DRAGGED)
  64     return true;
  65   if (event.IsMouseEvent() && (event.flags() & ui::EF_IS_SYNTHESIZED))
  66     return true;
  67   return false;
  68 }
  69
  70 }  // namespace
  71
  72 ////////////////////////////////////////////////////////////////////////////////
  73 // WindowEventDispatcher, public:
  74
  75 WindowEventDispatcher::WindowEventDispatcher(WindowTreeHost* host)
  76     : host_(host),
  77       touch_ids_down_(0),
  78       mouse_pressed_handler_(NULL),
  79       mouse_moved_handler_(NULL),
  80       event_dispatch_target_(NULL),
  81       old_dispatch_target_(NULL),
  82       synthesize_mouse_move_(false),
  83       move_hold_count_(0),
  84       dispatching_held_event_(false),
  85       observer_manager_(this),
  86       repost_event_factory_(this),
  87       held_event_factory_(this) {
  88   ui::GestureRecognizer::Get()->AddGestureEventHelper(this);
  89   Env::GetInstance()->AddObserver(this);
  90 }
  91
  92 WindowEventDispatcher::~WindowEventDispatcher() {
  93   TRACE_EVENT0("shutdown", "WindowEventDispatcher::Destructor");
  94   Env::GetInstance()->RemoveObserver(this);
  95   ui::GestureRecognizer::Get()->RemoveGestureEventHelper(this);
  96 }
  97
  98 void WindowEventDispatcher::RepostEvent(const ui::LocatedEvent& event) {
  99   DCHECK(event.type() == ui::ET_MOUSE_PRESSED ||
 100          event.type() == ui::ET_GESTURE_TAP_DOWN);
 101   // We allow for only one outstanding repostable event. This is used
 102   // in exiting context menus.  A dropped repost request is allowed.
 103   if (event.type() == ui::ET_MOUSE_PRESSED) {
 104     held_repostable_event_.reset(
 105         new ui::MouseEvent(
 106             static_cast<const ui::MouseEvent&>(event),
 107             static_cast<aura::Window*>(event.target()),
 108             window()));
 109     base::MessageLoop::current()->PostNonNestableTask(
 110         FROM_HERE, base::Bind(
 111             base::IgnoreResult(&WindowEventDispatcher::DispatchHeldEvents),
 112             repost_event_factory_.GetWeakPtr()));
 113   } else {
 114     DCHECK(event.type() == ui::ET_GESTURE_TAP_DOWN);
 115     held_repostable_event_.reset();
 116     // TODO(rbyers): Reposing of gestures is tricky to get
 117     // right, so it's not yet supported.  crbug.com/170987.
 118   }
 119 }
 120
 121 void WindowEventDispatcher::OnMouseEventsEnableStateChanged(bool enabled) {
 122   // Send entered / exited so that visual state can be updated to match
 123   // mouse events state.
 124   PostSynthesizeMouseMove();
 125   // TODO(mazda): Add code to disable mouse events when |enabled| == false.
 126 }
 127
 128 void WindowEventDispatcher::DispatchCancelModeEvent() {
 129   ui::CancelModeEvent event;
 130   Window* focused_window = client::GetFocusClient(window())->GetFocusedWindow();
 131   if (focused_window && !window()->Contains(focused_window))
 132     focused_window = NULL;
 133   DispatchDetails details =
 134       DispatchEvent(focused_window ? focused_window : window(), &event);
 135   if (details.dispatcher_destroyed)
 136     return;
 137 }
 138
 139 void WindowEventDispatcher::DispatchGestureEvent(ui::GestureEvent* event) {
 140   DispatchDetails details = DispatchHeldEvents();
 141   if (details.dispatcher_destroyed)
 142     return;
 143
 144   Window* target = GetGestureTarget(event);
 145   if (target) {
 146     event->ConvertLocationToTarget(window(), target);
 147     DispatchDetails details = DispatchEvent(target, event);
 148     if (details.dispatcher_destroyed)
 149       return;
 150   }
 151 }
 152
 153 void WindowEventDispatcher::DispatchMouseExitAtPoint(const gfx::Point& point) {
 154   ui::MouseEvent event(ui::ET_MOUSE_EXITED, point, point, ui::EF_NONE,
 155                        ui::EF_NONE);
 156   DispatchDetails details =
 157       DispatchMouseEnterOrExit(event, ui::ET_MOUSE_EXITED);
 158   if (details.dispatcher_destroyed)
 159     return;
 160 }
 161
 162 void WindowEventDispatcher::ProcessedTouchEvent(ui::TouchEvent* event,
 163                                                 Window* window,
 164                                                 ui::EventResult result) {
 165   scoped_ptr<ui::GestureRecognizer::Gestures> gestures;
 166   gestures.reset(ui::GestureRecognizer::Get()->
 167       ProcessTouchEventForGesture(*event, result, window));
 168   DispatchDetails details = ProcessGestures(gestures.get());
 169   if (details.dispatcher_destroyed)
 170     return;
 171 }
 172
 173 void WindowEventDispatcher::HoldPointerMoves() {
 174   if (!move_hold_count_)
 175     held_event_factory_.InvalidateWeakPtrs();
 176   ++move_hold_count_;
 177   TRACE_EVENT_ASYNC_BEGIN0("ui", "WindowEventDispatcher::HoldPointerMoves",
 178                            this);
 179 }
 180
 181 void WindowEventDispatcher::ReleasePointerMoves() {
 182   --move_hold_count_;
 183   DCHECK_GE(move_hold_count_, 0);
 184   if (!move_hold_count_ && held_move_event_) {
 185     // We don't want to call DispatchHeldEvents directly, because this might be
 186     // called from a deep stack while another event, in which case dispatching
 187     // another one may not be safe/expected.  Instead we post a task, that we
 188     // may cancel if HoldPointerMoves is called again before it executes.
 189     base::MessageLoop::current()->PostNonNestableTask(
 190         FROM_HERE, base::Bind(
 191           base::IgnoreResult(&WindowEventDispatcher::DispatchHeldEvents),
 192           held_event_factory_.GetWeakPtr()));
 193   }
 194   TRACE_EVENT_ASYNC_END0("ui", "WindowEventDispatcher::HoldPointerMoves", this);
 195 }
 196
 197 gfx::Point WindowEventDispatcher::GetLastMouseLocationInRoot() const {
 198   gfx::Point location = Env::GetInstance()->last_mouse_location();
 199   client::ScreenPositionClient* client =
 200       client::GetScreenPositionClient(window());
 201   if (client)
 202     client->ConvertPointFromScreen(window(), &location);
 203   return location;
 204 }
 205
 206 void WindowEventDispatcher::OnHostLostMouseGrab() {
 207   mouse_pressed_handler_ = NULL;
 208   mouse_moved_handler_ = NULL;
 209 }
 210
 211 void WindowEventDispatcher::OnCursorMovedToRootLocation(
 212     const gfx::Point& root_location) {
 213   SetLastMouseLocation(window(), root_location);
 214   synthesize_mouse_move_ = false;
 215 }
 216
 217 void WindowEventDispatcher::OnPostNotifiedWindowDestroying(Window* window) {
 218   OnWindowHidden(window, WINDOW_DESTROYED);
 219 }
 220
 221 ////////////////////////////////////////////////////////////////////////////////
 222 // WindowEventDispatcher, private:
 223
 224 Window* WindowEventDispatcher::window() {
 225   return host_->window();
 226 }
 227
 228 const Window* WindowEventDispatcher::window() const {
 229   return host_->window();
 230 }
 231
 232 void WindowEventDispatcher::TransformEventForDeviceScaleFactor(
 233     ui::LocatedEvent* event) {
 234   event->UpdateForRootTransform(host_->GetInverseRootTransform());
 235 }
 236
 237 void WindowEventDispatcher::DispatchMouseExitToHidingWindow(Window* window) {
 238   // The mouse capture is intentionally ignored. Think that a mouse enters
 239   // to a window, the window sets the capture, the mouse exits the window,
 240   // and then it releases the capture. In that case OnMouseExited won't
 241   // be called. So it is natural not to emit OnMouseExited even though
 242   // |window| is the capture window.
 243   gfx::Point last_mouse_location = GetLastMouseLocationInRoot();
 244   if (window->Contains(mouse_moved_handler_) &&
 245       window->ContainsPointInRoot(last_mouse_location))
 246     DispatchMouseExitAtPoint(last_mouse_location);
 247 }
 248
 249 ui::EventDispatchDetails WindowEventDispatcher::DispatchMouseEnterOrExit(
 250     const ui::MouseEvent& event,
 251     ui::EventType type) {
 252   if (event.type() != ui::ET_MOUSE_CAPTURE_CHANGED &&
 253       !(event.flags() & ui::EF_IS_SYNTHESIZED)) {
 254     SetLastMouseLocation(window(), event.root_location());
 255   }
 256
 257   if (!mouse_moved_handler_ || !mouse_moved_handler_->delegate() ||
 258       !window()->Contains(mouse_moved_handler_))
 259     return DispatchDetails();
 260
 261   // |event| may be an event in the process of being dispatched to a target (in
 262   // which case its locations will be in the event's target's coordinate
 263   // system), or a synthetic event created in root-window (in which case, the
 264   // event's target will be NULL, and the event will be in the root-window's
 265   // coordinate system.
 266   aura::Window* target = static_cast<Window*>(event.target());
 267   if (!target)
 268     target = window();
 269   ui::MouseEvent translated_event(event,
 270                                   target,
 271                                   mouse_moved_handler_,
 272                                   type,
 273                                   event.flags() | ui::EF_IS_SYNTHESIZED);
 274   return DispatchEvent(mouse_moved_handler_, &translated_event);
 275 }
 276
 277 ui::EventDispatchDetails WindowEventDispatcher::ProcessGestures(
 278     ui::GestureRecognizer::Gestures* gestures) {
 279   DispatchDetails details;
 280   if (!gestures || gestures->empty())
 281     return details;
 282
 283   Window* target = GetGestureTarget(gestures->get().at(0));
 284   for (size_t i = 0; i < gestures->size(); ++i) {
 285     ui::GestureEvent* event = gestures->get().at(i);
 286     event->ConvertLocationToTarget(window(), target);
 287     details = DispatchEvent(target, event);
 288     if (details.dispatcher_destroyed || details.target_destroyed)
 289       break;
 290   }
 291   return details;
 292 }
 293
 294 void WindowEventDispatcher::OnWindowHidden(Window* invisible,
 295                                            WindowHiddenReason reason) {
 296   // If the window the mouse was pressed in becomes invisible, it should no
 297   // longer receive mouse events.
 298   if (invisible->Contains(mouse_pressed_handler_))
 299     mouse_pressed_handler_ = NULL;
 300   if (invisible->Contains(mouse_moved_handler_))
 301     mouse_moved_handler_ = NULL;
 302
 303   // If events are being dispatched from a nested message-loop, and the target
 304   // of the outer loop is hidden or moved to another dispatcher during
 305   // dispatching events in the inner loop, then reset the target for the outer
 306   // loop.
 307   if (invisible->Contains(old_dispatch_target_))
 308     old_dispatch_target_ = NULL;
 309
 310   invisible->CleanupGestureState();
 311
 312   // Do not clear the capture, and the |event_dispatch_target_| if the
 313   // window is moving across hosts, because the target itself is actually still
 314   // visible and clearing them stops further event processing, which can cause
 315   // unexpected behaviors. See crbug.com/157583
 316   if (reason != WINDOW_MOVING) {
 317     // We don't ask |invisible| here, because invisible may have been removed
 318     // from the window hierarchy already by the time this function is called
 319     // (OnWindowDestroyed).
 320     client::CaptureClient* capture_client =
 321         client::GetCaptureClient(host_->window());
 322     Window* capture_window =
 323         capture_client ? capture_client->GetCaptureWindow() : NULL;
 324
 325     if (invisible->Contains(event_dispatch_target_))
 326       event_dispatch_target_ = NULL;
 327
 328     // If the ancestor of the capture window is hidden, release the capture.
 329     // Note that this may delete the window so do not use capture_window
 330     // after this.
 331     if (invisible->Contains(capture_window) && invisible != window())
 332       capture_window->ReleaseCapture();
 333   }
 334 }
 335
 336 Window* WindowEventDispatcher::GetGestureTarget(ui::GestureEvent* event) {
 337   Window* target = NULL;
 338   if (!event->IsEndingEvent()) {
 339     // The window that received the start event (e.g. scroll begin) needs to
 340     // receive the end event (e.g. scroll end).
 341     target = client::GetCaptureWindow(window());
 342   }
 343   if (!target) {
 344     target = ConsumerToWindow(
 345         ui::GestureRecognizer::Get()->GetTargetForGestureEvent(*event));
 346   }
 347
 348   return target;
 349 }
 350
 351 ////////////////////////////////////////////////////////////////////////////////
 352 // WindowEventDispatcher, aura::client::CaptureDelegate implementation:
 353
 354 void WindowEventDispatcher::UpdateCapture(Window* old_capture,
 355                                           Window* new_capture) {
 356   // |mouse_moved_handler_| may have been set to a Window in a different root
 357   // (see below). Clear it here to ensure we don't end up referencing a stale
 358   // Window.
 359   if (mouse_moved_handler_ && !window()->Contains(mouse_moved_handler_))
 360     mouse_moved_handler_ = NULL;
 361
 362   if (old_capture && old_capture->GetRootWindow() == window() &&
 363       old_capture->delegate()) {
 364     // Send a capture changed event with bogus location data.
 365     ui::MouseEvent event(ui::ET_MOUSE_CAPTURE_CHANGED, gfx::Point(),
 366                          gfx::Point(), 0, 0);
 367
 368     DispatchDetails details = DispatchEvent(old_capture, &event);
 369     if (details.dispatcher_destroyed)
 370       return;
 371
 372     old_capture->delegate()->OnCaptureLost();
 373   }
 374
 375   if (new_capture) {
 376     // Make all subsequent mouse events go to the capture window. We shouldn't
 377     // need to send an event here as OnCaptureLost() should take care of that.
 378     if (mouse_moved_handler_ || Env::GetInstance()->IsMouseButtonDown())
 379       mouse_moved_handler_ = new_capture;
 380   } else {
 381     // Make sure mouse_moved_handler gets updated.
 382     DispatchDetails details = SynthesizeMouseMoveEvent();
 383     if (details.dispatcher_destroyed)
 384       return;
 385   }
 386   mouse_pressed_handler_ = NULL;
 387 }
 388
 389 void WindowEventDispatcher::OnOtherRootGotCapture() {
 390   mouse_moved_handler_ = NULL;
 391   mouse_pressed_handler_ = NULL;
 392 }
 393
 394 void WindowEventDispatcher::SetNativeCapture() {
 395   host_->SetCapture();
 396 }
 397
 398 void WindowEventDispatcher::ReleaseNativeCapture() {
 399   host_->ReleaseCapture();
 400 }
 401
 402 ////////////////////////////////////////////////////////////////////////////////
 403 // WindowEventDispatcher, ui::EventProcessor implementation:
 404 ui::EventTarget* WindowEventDispatcher::GetRootTarget() {
 405   return window();
 406 }
 407
 408 void WindowEventDispatcher::PrepareEventForDispatch(ui::Event* event) {
 409   if (dispatching_held_event_) {
 410     // The held events are already in |window()|'s coordinate system. So it is
 411     // not necessary to apply the transform to convert from the host's
 412     // coordinate system to |window()|'s coordinate system.
 413     return;
 414   }
 415   if (event->IsMouseEvent() ||
 416       event->IsScrollEvent() ||
 417       event->IsTouchEvent() ||
 418       event->IsGestureEvent()) {
 419     TransformEventForDeviceScaleFactor(static_cast<ui::LocatedEvent*>(event));
 420   }
 421 }
 422
 423 ////////////////////////////////////////////////////////////////////////////////
 424 // WindowEventDispatcher, ui::EventDispatcherDelegate implementation:
 425
 426 bool WindowEventDispatcher::CanDispatchToTarget(ui::EventTarget* target) {
 427   return event_dispatch_target_ == target;
 428 }
 429
 430 ui::EventDispatchDetails WindowEventDispatcher::PreDispatchEvent(
 431     ui::EventTarget* target,
 432     ui::Event* event) {
 433   Window* target_window = static_cast<Window*>(target);
 434   CHECK(window()->Contains(target_window));
 435
 436   if (!dispatching_held_event_) {
 437     bool can_be_held = IsEventCandidateForHold(*event);
 438     if (!move_hold_count_ || !can_be_held) {
 439       if (can_be_held)
 440         held_move_event_.reset();
 441       DispatchDetails details = DispatchHeldEvents();
 442       if (details.dispatcher_destroyed || details.target_destroyed)
 443         return details;
 444     }
 445   }
 446
 447   if (event->IsMouseEvent()) {
 448     PreDispatchMouseEvent(target_window, static_cast<ui::MouseEvent*>(event));
 449   } else if (event->IsScrollEvent()) {
 450     PreDispatchLocatedEvent(target_window,
 451                             static_cast<ui::ScrollEvent*>(event));
 452   } else if (event->IsTouchEvent()) {
 453     PreDispatchTouchEvent(target_window, static_cast<ui::TouchEvent*>(event));
 454   }
 455   old_dispatch_target_ = event_dispatch_target_;
 456   event_dispatch_target_ = static_cast<Window*>(target);
 457   return DispatchDetails();
 458 }
 459
 460 ui::EventDispatchDetails WindowEventDispatcher::PostDispatchEvent(
 461     ui::EventTarget* target,
 462     const ui::Event& event) {
 463   DispatchDetails details;
 464   if (!target || target != event_dispatch_target_)
 465     details.target_destroyed = true;
 466   event_dispatch_target_ = old_dispatch_target_;
 467   old_dispatch_target_ = NULL;
 468 #ifndef NDEBUG
 469   DCHECK(!event_dispatch_target_ || window()->Contains(event_dispatch_target_));
 470 #endif
 471
 472   if (event.IsTouchEvent() && !details.target_destroyed) {
 473     // Do not let 'held' touch events contribute to any gestures.
 474     if (!held_move_event_ || !held_move_event_->IsTouchEvent()) {
 475       ui::TouchEvent orig_event(static_cast<const ui::TouchEvent&>(event),
 476                                 static_cast<Window*>(event.target()), window());
 477       // Get the list of GestureEvents from GestureRecognizer.
 478       scoped_ptr<ui::GestureRecognizer::Gestures> gestures;
 479       gestures.reset(ui::GestureRecognizer::Get()->
 480           ProcessTouchEventForGesture(orig_event, event.result(),
 481                                       static_cast<Window*>(target)));
 482       return ProcessGestures(gestures.get());
 483     }
 484   }
 485
 486   return details;
 487 }
 488
 489 ////////////////////////////////////////////////////////////////////////////////
 490 // WindowEventDispatcher, ui::GestureEventHelper implementation:
 491
 492 bool WindowEventDispatcher::CanDispatchToConsumer(
 493     ui::GestureConsumer* consumer) {
 494   Window* consumer_window = ConsumerToWindow(consumer);
 495   return (consumer_window && consumer_window->GetRootWindow() == window());
 496 }
 497
 498 void WindowEventDispatcher::DispatchPostponedGestureEvent(
 499     ui::GestureEvent* event) {
 500   DispatchGestureEvent(event);
 501 }
 502
 503 void WindowEventDispatcher::DispatchCancelTouchEvent(ui::TouchEvent* event) {
 504   DispatchDetails details = OnEventFromSource(event);
 505   if (details.dispatcher_destroyed)
 506     return;
 507 }
 508
 509 ////////////////////////////////////////////////////////////////////////////////
 510 // WindowEventDispatcher, WindowObserver implementation:
 511
 512 void WindowEventDispatcher::OnWindowDestroying(Window* window) {
 513   if (!host_->window()->Contains(window))
 514     return;
 515
 516   DispatchMouseExitToHidingWindow(window);
 517   SynthesizeMouseMoveAfterChangeToWindow(window);
 518 }
 519
 520 void WindowEventDispatcher::OnWindowDestroyed(Window* window) {
 521   // We observe all windows regardless of what root Window (if any) they're
 522   // attached to.
 523   observer_manager_.Remove(window);
 524 }
 525
 526 void WindowEventDispatcher::OnWindowAddedToRootWindow(Window* attached) {
 527   if (!observer_manager_.IsObserving(attached))
 528     observer_manager_.Add(attached);
 529
 530   if (!host_->window()->Contains(attached))
 531     return;
 532
 533   SynthesizeMouseMoveAfterChangeToWindow(attached);
 534 }
 535
 536 void WindowEventDispatcher::OnWindowRemovingFromRootWindow(Window* detached,
 537                                                            Window* new_root) {
 538   if (!host_->window()->Contains(detached))
 539     return;
 540
 541   DCHECK(client::GetCaptureWindow(window()) != window());
 542
 543   DispatchMouseExitToHidingWindow(detached);
 544   SynthesizeMouseMoveAfterChangeToWindow(detached);
 545
 546   // Hiding the window releases capture which can implicitly destroy the window
 547   // so the window may no longer be valid after this call.
 548   OnWindowHidden(detached, new_root ? WINDOW_MOVING : WINDOW_HIDDEN);
 549 }
 550
 551 void WindowEventDispatcher::OnWindowVisibilityChanging(Window* window,
 552                                                        bool visible) {
 553   if (!host_->window()->Contains(window))
 554     return;
 555
 556   DispatchMouseExitToHidingWindow(window);
 557 }
 558
 559 void WindowEventDispatcher::OnWindowVisibilityChanged(Window* window,
 560                                                       bool visible) {
 561   if (!host_->window()->Contains(window))
 562     return;
 563
 564   if (window->ContainsPointInRoot(GetLastMouseLocationInRoot()))
 565     PostSynthesizeMouseMove();
 566
 567   // Hiding the window releases capture which can implicitly destroy the window
 568   // so the window may no longer be valid after this call.
 569   if (!visible)
 570     OnWindowHidden(window, WINDOW_HIDDEN);
 571 }
 572
 573 void WindowEventDispatcher::OnWindowBoundsChanged(Window* window,
 574                                                   const gfx::Rect& old_bounds,
 575                                                   const gfx::Rect& new_bounds) {
 576   if (!host_->window()->Contains(window))
 577     return;
 578
 579   if (window == host_->window()) {
 580     TRACE_EVENT1("ui", "WindowEventDispatcher::OnWindowBoundsChanged(root)",
 581                  "size", new_bounds.size().ToString());
 582
 583     DispatchDetails details = DispatchHeldEvents();
 584     if (details.dispatcher_destroyed)
 585       return;
 586
 587     // Constrain the mouse position within the new root Window size.
 588     gfx::Point point;
 589     if (host_->QueryMouseLocation(&point)) {
 590       SetLastMouseLocation(
 591           host_->window(),
 592           ui::ConvertPointToDIP(host_->window()->layer(), point));
 593     }
 594     synthesize_mouse_move_ = false;
 595   }
 596
 597   if (window->IsVisible()) {
 598     gfx::Rect old_bounds_in_root = old_bounds, new_bounds_in_root = new_bounds;
 599     Window::ConvertRectToTarget(window->parent(), host_->window(),
 600                                 &old_bounds_in_root);
 601     Window::ConvertRectToTarget(window->parent(), host_->window(),
 602                                 &new_bounds_in_root);
 603     gfx::Point last_mouse_location = GetLastMouseLocationInRoot();
 604     if (old_bounds_in_root.Contains(last_mouse_location) !=
 605         new_bounds_in_root.Contains(last_mouse_location)) {
 606       PostSynthesizeMouseMove();
 607     }
 608   }
 609 }
 610
 611 void WindowEventDispatcher::OnWindowTransforming(Window* window) {
 612   if (!host_->window()->Contains(window))
 613     return;
 614
 615   SynthesizeMouseMoveAfterChangeToWindow(window);
 616 }
 617
 618 void WindowEventDispatcher::OnWindowTransformed(Window* window) {
 619   if (!host_->window()->Contains(window))
 620     return;
 621
 622   SynthesizeMouseMoveAfterChangeToWindow(window);
 623 }
 624
 625 ///////////////////////////////////////////////////////////////////////////////
 626 // WindowEventDispatcher, EnvObserver implementation:
 627
 628 void WindowEventDispatcher::OnWindowInitialized(Window* window) {
 629   observer_manager_.Add(window);
 630 }
 631
 632 ////////////////////////////////////////////////////////////////////////////////
 633 // WindowEventDispatcher, private:
 634
 635 ui::EventDispatchDetails WindowEventDispatcher::DispatchHeldEvents() {
 636   if (!held_repostable_event_ && !held_move_event_)
 637     return DispatchDetails();
 638
 639   CHECK(!dispatching_held_event_);
 640   dispatching_held_event_ = true;
 641
 642   DispatchDetails dispatch_details;
 643   if (held_repostable_event_) {
 644     if (held_repostable_event_->type() == ui::ET_MOUSE_PRESSED) {
 645       scoped_ptr<ui::MouseEvent> mouse_event(
 646           static_cast<ui::MouseEvent*>(held_repostable_event_.release()));
 647       dispatch_details = OnEventFromSource(mouse_event.get());
 648     } else {
 649       // TODO(rbyers): GESTURE_TAP_DOWN not yet supported: crbug.com/170987.
 650       NOTREACHED();
 651     }
 652     if (dispatch_details.dispatcher_destroyed)
 653       return dispatch_details;
 654   }
 655
 656   if (held_move_event_) {
 657     // If a mouse move has been synthesized, the target location is suspect,
 658     // so drop the held mouse event.
 659     if (held_move_event_->IsTouchEvent() ||
 660         (held_move_event_->IsMouseEvent() && !synthesize_mouse_move_)) {
 661       dispatch_details = OnEventFromSource(held_move_event_.get());
 662     }
 663     if (!dispatch_details.dispatcher_destroyed)
 664       held_move_event_.reset();
 665   }
 666
 667   if (!dispatch_details.dispatcher_destroyed)
 668     dispatching_held_event_ = false;
 669   return dispatch_details;
 670 }
 671
 672 void WindowEventDispatcher::PostSynthesizeMouseMove() {
 673   if (synthesize_mouse_move_)
 674     return;
 675   synthesize_mouse_move_ = true;
 676   base::MessageLoop::current()->PostNonNestableTask(
 677       FROM_HERE,
 678       base::Bind(base::IgnoreResult(
 679           &WindowEventDispatcher::SynthesizeMouseMoveEvent),
 680           held_event_factory_.GetWeakPtr()));
 681 }
 682
 683 void WindowEventDispatcher::SynthesizeMouseMoveAfterChangeToWindow(
 684     Window* window) {
 685   if (window->IsVisible() &&
 686       window->ContainsPointInRoot(GetLastMouseLocationInRoot())) {
 687     PostSynthesizeMouseMove();
 688   }
 689 }
 690
 691 ui::EventDispatchDetails WindowEventDispatcher::SynthesizeMouseMoveEvent() {
 692   DispatchDetails details;
 693   if (!synthesize_mouse_move_)
 694     return details;
 695   synthesize_mouse_move_ = false;
 696   gfx::Point root_mouse_location = GetLastMouseLocationInRoot();
 697   if (!window()->bounds().Contains(root_mouse_location))
 698     return details;
 699   gfx::Point host_mouse_location = root_mouse_location;
 700   host_->ConvertPointToHost(&host_mouse_location);
 701   ui::MouseEvent event(ui::ET_MOUSE_MOVED,
 702                        host_mouse_location,
 703                        host_mouse_location,
 704                        ui::EF_IS_SYNTHESIZED,
 705                        0);
 706   return OnEventFromSource(&event);
 707 }
 708
 709 void WindowEventDispatcher::PreDispatchLocatedEvent(Window* target,
 710                                                     ui::LocatedEvent* event) {
 711   int flags = event->flags();
 712   if (IsNonClientLocation(target, event->location()))
 713     flags |= ui::EF_IS_NON_CLIENT;
 714   event->set_flags(flags);
 715
 716   if (!dispatching_held_event_ &&
 717       (event->IsMouseEvent() || event->IsScrollEvent()) &&
 718       !(event->flags() & ui::EF_IS_SYNTHESIZED)) {
 719     if (event->type() != ui::ET_MOUSE_CAPTURE_CHANGED)
 720       SetLastMouseLocation(window(), event->root_location());
 721     synthesize_mouse_move_ = false;
 722   }
 723 }
 724
 725 void WindowEventDispatcher::PreDispatchMouseEvent(Window* target,
 726                                                   ui::MouseEvent* event) {
 727   client::CursorClient* cursor_client = client::GetCursorClient(window());
 728   // We allow synthesized mouse exit events through even if mouse events are
 729   // disabled. This ensures that hover state, etc on controls like buttons is
 730   // cleared.
 731   if (cursor_client &&
 732       !cursor_client->IsMouseEventsEnabled() &&
 733       (event->flags() & ui::EF_IS_SYNTHESIZED) &&
 734       (event->type() != ui::ET_MOUSE_EXITED)) {
 735     event->SetHandled();
 736     return;
 737   }
 738
 739   if (IsEventCandidateForHold(*event) && !dispatching_held_event_) {
 740     if (move_hold_count_) {
 741       if (!(event->flags() & ui::EF_IS_SYNTHESIZED) &&
 742           event->type() != ui::ET_MOUSE_CAPTURE_CHANGED) {
 743         SetLastMouseLocation(window(), event->root_location());
 744       }
 745       held_move_event_.reset(new ui::MouseEvent(*event, target, window()));
 746       event->SetHandled();
 747       return;
 748     } else {
 749       // We may have a held event for a period between the time move_hold_count_
 750       // fell to 0 and the DispatchHeldEvents executes. Since we're going to
 751       // dispatch the new event directly below, we can reset the old one.
 752       held_move_event_.reset();
 753     }
 754   }
 755
 756   const int kMouseButtonFlagMask = ui::EF_LEFT_MOUSE_BUTTON |
 757                                    ui::EF_MIDDLE_MOUSE_BUTTON |
 758                                    ui::EF_RIGHT_MOUSE_BUTTON;
 759   switch (event->type()) {
 760     case ui::ET_MOUSE_EXITED:
 761       if (!target || target == window()) {
 762         DispatchDetails details =
 763             DispatchMouseEnterOrExit(*event, ui::ET_MOUSE_EXITED);
 764         if (details.dispatcher_destroyed) {
 765           event->SetHandled();
 766           return;
 767         }
 768         mouse_moved_handler_ = NULL;
 769       }
 770       break;
 771     case ui::ET_MOUSE_MOVED:
 772       // Send an exit to the current |mouse_moved_handler_| and an enter to
 773       // |target|. Take care that both us and |target| aren't destroyed during
 774       // dispatch.
 775       if (target != mouse_moved_handler_) {
 776         aura::Window* old_mouse_moved_handler = mouse_moved_handler_;
 777         WindowTracker live_window;
 778         live_window.Add(target);
 779         DispatchDetails details =
 780             DispatchMouseEnterOrExit(*event, ui::ET_MOUSE_EXITED);
 781         if (details.dispatcher_destroyed) {
 782           event->SetHandled();
 783           return;
 784         }
 785         // If the |mouse_moved_handler_| changes out from under us, assume a
 786         // nested message loop ran and we don't need to do anything.
 787         if (mouse_moved_handler_ != old_mouse_moved_handler) {
 788           event->SetHandled();
 789           return;
 790         }
 791         if (!live_window.Contains(target) || details.target_destroyed) {
 792           mouse_moved_handler_ = NULL;
 793           event->SetHandled();
 794           return;
 795         }
 796         live_window.Remove(target);
 797
 798         mouse_moved_handler_ = target;
 799         details = DispatchMouseEnterOrExit(*event, ui::ET_MOUSE_ENTERED);
 800         if (details.dispatcher_destroyed || details.target_destroyed) {
 801           event->SetHandled();
 802           return;
 803         }
 804       }
 805       break;
 806     case ui::ET_MOUSE_PRESSED:
 807       // Don't set the mouse pressed handler for non client mouse down events.
 808       // These are only sent by Windows and are not always followed with non
 809       // client mouse up events which causes subsequent mouse events to be
 810       // sent to the wrong target.
 811       if (!(event->flags() & ui::EF_IS_NON_CLIENT) && !mouse_pressed_handler_)
 812         mouse_pressed_handler_ = target;
 813       Env::GetInstance()->set_mouse_button_flags(
 814           event->flags() & kMouseButtonFlagMask);
 815       break;
 816     case ui::ET_MOUSE_RELEASED:
 817       mouse_pressed_handler_ = NULL;
 818       Env::GetInstance()->set_mouse_button_flags(event->flags() &
 819           kMouseButtonFlagMask & ~event->changed_button_flags());
 820       break;
 821     default:
 822       break;
 823   }
 824
 825   PreDispatchLocatedEvent(target, event);
 826 }
 827
 828 void WindowEventDispatcher::PreDispatchTouchEvent(Window* target,
 829                                                   ui::TouchEvent* event) {
 830   switch (event->type()) {
 831     case ui::ET_TOUCH_PRESSED:
 832       touch_ids_down_ |= (1 << event->touch_id());
 833       Env::GetInstance()->set_touch_down(touch_ids_down_ != 0);
 834       break;
 835
 836       // Handle ET_TOUCH_CANCELLED only if it has a native event.
 837     case ui::ET_TOUCH_CANCELLED:
 838       if (!event->HasNativeEvent())
 839         break;
 840       // fallthrough
 841     case ui::ET_TOUCH_RELEASED:
 842       touch_ids_down_ = (touch_ids_down_ | (1 << event->touch_id())) ^
 843             (1 << event->touch_id());
 844       Env::GetInstance()->set_touch_down(touch_ids_down_ != 0);
 845       break;
 846
 847     case ui::ET_TOUCH_MOVED:
 848       if (move_hold_count_ && !dispatching_held_event_) {
 849         held_move_event_.reset(new ui::TouchEvent(*event, target, window()));
 850         event->SetHandled();
 851         return;
 852       }
 853       break;
 854
 855     default:
 856       NOTREACHED();
 857       break;
 858   }
 859   PreDispatchLocatedEvent(target, event);
 860 }
 861
 862 }  // namespace aura