src/ash/wm/session_state_animator_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 "ash/wm/session_state_animator_impl.h"
   6
   7 #include <vector>
   8
   9 #include "ash/shell.h"
  10 #include "ash/shell_window_ids.h"
  11 #include "ash/wm/window_animations.h"
  12 #include "ui/aura/client/aura_constants.h"
  13 #include "ui/aura/window_event_dispatcher.h"
  14 #include "ui/compositor/layer_animation_observer.h"
  15 #include "ui/compositor/layer_animation_sequence.h"
  16 #include "ui/compositor/scoped_layer_animation_settings.h"
  17 #include "ui/views/widget/widget.h"
  18
  19 namespace ash {
  20 namespace {
  21
  22 // Slightly-smaller size that we scale the screen down to for the pre-lock and
  23 // pre-shutdown states.
  24 const float kSlowCloseSizeRatio = 0.95f;
  25
  26 // Maximum opacity of white layer when animating pre-shutdown state.
  27 const float kPartialFadeRatio = 0.3f;
  28
  29 // Minimum size. Not zero as it causes numeric issues.
  30 const float kMinimumScale = 1e-4f;
  31
  32 // Returns the primary root window's container.
  33 aura::Window* GetBackground() {
  34   aura::Window* root_window = Shell::GetPrimaryRootWindow();
  35   return Shell::GetContainer(root_window,
  36                              kShellWindowId_DesktopBackgroundContainer);
  37 }
  38
  39 // Returns the transform that should be applied to containers for the slow-close
  40 // animation.
  41 gfx::Transform GetSlowCloseTransform() {
  42   gfx::Size root_size = Shell::GetPrimaryRootWindow()->bounds().size();
  43   gfx::Transform transform;
  44   transform.Translate(
  45       floor(0.5 * (1.0 - kSlowCloseSizeRatio) * root_size.width() + 0.5),
  46       floor(0.5 * (1.0 - kSlowCloseSizeRatio) * root_size.height() + 0.5));
  47   transform.Scale(kSlowCloseSizeRatio, kSlowCloseSizeRatio);
  48   return transform;
  49 }
  50
  51 // Returns the transform that should be applied to containers for the fast-close
  52 // animation.
  53 gfx::Transform GetFastCloseTransform() {
  54   gfx::Size root_size = Shell::GetPrimaryRootWindow()->bounds().size();
  55   gfx::Transform transform;
  56
  57   transform.Translate(floor(0.5 * root_size.width() + 0.5),
  58                       floor(0.5 * root_size.height() + 0.5));
  59   transform.Scale(kMinimumScale, kMinimumScale);
  60   return transform;
  61 }
  62
  63 // Slowly shrinks |window| to a slightly-smaller size.
  64 void StartSlowCloseAnimationForWindow(aura::Window* window,
  65                                       base::TimeDelta duration,
  66                                       ui::LayerAnimationObserver* observer) {
  67   ui::LayerAnimator* animator = window->layer()->GetAnimator();
  68   animator->set_preemption_strategy(
  69       ui::LayerAnimator::IMMEDIATELY_ANIMATE_TO_NEW_TARGET);
  70   ui::LayerAnimationSequence* sequence = new ui::LayerAnimationSequence(
  71       ui::LayerAnimationElement::CreateTransformElement(
  72           GetSlowCloseTransform(),
  73           duration));
  74   if (observer)
  75     sequence->AddObserver(observer);
  76   animator->StartAnimation(sequence);
  77 }
  78
  79 // Quickly undoes the effects of the slow-close animation on |window|.
  80 void StartUndoSlowCloseAnimationForWindow(
  81     aura::Window* window,
  82     base::TimeDelta duration,
  83     ui::LayerAnimationObserver* observer) {
  84   ui::LayerAnimator* animator = window->layer()->GetAnimator();
  85   animator->set_preemption_strategy(
  86       ui::LayerAnimator::IMMEDIATELY_ANIMATE_TO_NEW_TARGET);
  87   ui::LayerAnimationSequence* sequence = new ui::LayerAnimationSequence(
  88       ui::LayerAnimationElement::CreateTransformElement(
  89           gfx::Transform(),
  90           duration));
  91   if (observer)
  92     sequence->AddObserver(observer);
  93   animator->StartAnimation(sequence);
  94 }
  95
  96 // Quickly shrinks |window| down to a point in the center of the screen and
  97 // fades it out to 0 opacity.
  98 void StartFastCloseAnimationForWindow(aura::Window* window,
  99                                       base::TimeDelta duration,
 100                                       ui::LayerAnimationObserver* observer) {
 101   ui::LayerAnimator* animator = window->layer()->GetAnimator();
 102   animator->set_preemption_strategy(
 103       ui::LayerAnimator::IMMEDIATELY_ANIMATE_TO_NEW_TARGET);
 104   animator->StartAnimation(
 105       new ui::LayerAnimationSequence(
 106           ui::LayerAnimationElement::CreateTransformElement(
 107               GetFastCloseTransform(), duration)));
 108   ui::LayerAnimationSequence* sequence = new ui::LayerAnimationSequence(
 109       ui::LayerAnimationElement::CreateOpacityElement(0.0, duration));
 110   if (observer)
 111     sequence->AddObserver(observer);
 112   animator->StartAnimation(sequence);
 113 }
 114
 115 // Fades |window| to |target_opacity| over |duration|.
 116 void StartPartialFadeAnimation(aura::Window* window,
 117                                float target_opacity,
 118                                base::TimeDelta duration,
 119                                ui::LayerAnimationObserver* observer) {
 120   ui::LayerAnimator* animator = window->layer()->GetAnimator();
 121   animator->set_preemption_strategy(
 122       ui::LayerAnimator::IMMEDIATELY_ANIMATE_TO_NEW_TARGET);
 123   ui::LayerAnimationSequence* sequence = new ui::LayerAnimationSequence(
 124       ui::LayerAnimationElement::CreateOpacityElement(
 125           target_opacity, duration));
 126   if (observer)
 127     sequence->AddObserver(observer);
 128   animator->StartAnimation(sequence);
 129 }
 130
 131 // Fades |window| to |opacity| over |duration|.
 132 void StartOpacityAnimationForWindow(aura::Window* window,
 133                                     float opacity,
 134                                     base::TimeDelta duration,
 135                                     ui::LayerAnimationObserver* observer) {
 136   ui::LayerAnimator* animator = window->layer()->GetAnimator();
 137   animator->set_preemption_strategy(
 138       ui::LayerAnimator::IMMEDIATELY_ANIMATE_TO_NEW_TARGET);
 139   ui::LayerAnimationSequence* sequence = new ui::LayerAnimationSequence(
 140       ui::LayerAnimationElement::CreateOpacityElement(opacity, duration));
 141   if (observer)
 142     sequence->AddObserver(observer);
 143   animator->StartAnimation(sequence);
 144 }
 145
 146 // Makes |window| fully transparent instantaneously.
 147 void HideWindowImmediately(aura::Window* window,
 148                            ui::LayerAnimationObserver* observer) {
 149   window->layer()->SetOpacity(0.0);
 150   if (observer)
 151     observer->OnLayerAnimationEnded(NULL);
 152 }
 153
 154 // Restores |window| to its original position and scale and full opacity
 155 // instantaneously.
 156 void RestoreWindow(aura::Window* window, ui::LayerAnimationObserver* observer) {
 157   window->layer()->SetTransform(gfx::Transform());
 158   window->layer()->SetOpacity(1.0);
 159   if (observer)
 160     observer->OnLayerAnimationEnded(NULL);
 161 }
 162
 163 void HideWindow(aura::Window* window,
 164                 base::TimeDelta duration,
 165                 bool above,
 166                 ui::LayerAnimationObserver* observer) {
 167   ui::Layer* layer = window->layer();
 168   ui::ScopedLayerAnimationSettings settings(layer->GetAnimator());
 169
 170   settings.SetPreemptionStrategy(
 171       ui::LayerAnimator::IMMEDIATELY_ANIMATE_TO_NEW_TARGET);
 172   settings.SetTransitionDuration(duration);
 173
 174   settings.SetTweenType(gfx::Tween::EASE_OUT);
 175   SetTransformForScaleAnimation(layer,
 176       above ? LAYER_SCALE_ANIMATION_ABOVE : LAYER_SCALE_ANIMATION_BELOW);
 177
 178   settings.SetTweenType(gfx::Tween::EASE_IN_OUT);
 179   layer->SetOpacity(0.0f);
 180
 181   // After the animation completes snap the transform back to the identity,
 182   // otherwise any one that asks for screen bounds gets a slightly scaled
 183   // version.
 184   settings.SetPreemptionStrategy(ui::LayerAnimator::ENQUEUE_NEW_ANIMATION);
 185   settings.SetTransitionDuration(base::TimeDelta());
 186   layer->SetTransform(gfx::Transform());
 187
 188   // A bit of a dirty trick: we need to catch the end of the animation we don't
 189   // control. So we use two facts we know: which animator will be used and the
 190   // target opacity to add "Do nothing" animation sequence.
 191   // Unfortunately, we can not just use empty LayerAnimationSequence, because
 192   // it does not call NotifyEnded().
 193   if (observer) {
 194     ui::LayerAnimationSequence* sequence = new ui::LayerAnimationSequence(
 195         ui::LayerAnimationElement::CreateOpacityElement(
 196             0.0, base::TimeDelta()));
 197       sequence->AddObserver(observer);
 198     layer->GetAnimator()->ScheduleAnimation(sequence);
 199   }
 200 }
 201
 202 // Animates |window| to identity transform and full opacity over |duration|.
 203 void TransformWindowToBaseState(aura::Window* window,
 204                                 base::TimeDelta duration,
 205                                 ui::LayerAnimationObserver* observer) {
 206   ui::Layer* layer = window->layer();
 207   ui::ScopedLayerAnimationSettings settings(layer->GetAnimator());
 208
 209   // Animate to target values.
 210   settings.SetPreemptionStrategy(
 211       ui::LayerAnimator::IMMEDIATELY_ANIMATE_TO_NEW_TARGET);
 212   settings.SetTransitionDuration(duration);
 213
 214   settings.SetTweenType(gfx::Tween::EASE_OUT);
 215   layer->SetTransform(gfx::Transform());
 216
 217   settings.SetTweenType(gfx::Tween::EASE_IN_OUT);
 218   layer->SetOpacity(1.0f);
 219
 220   // A bit of a dirty trick: we need to catch the end of the animation we don't
 221   // control. So we use two facts we know: which animator will be used and the
 222   // target opacity to add "Do nothing" animation sequence.
 223   // Unfortunately, we can not just use empty LayerAnimationSequence, because
 224   // it does not call NotifyEnded().
 225   if (observer) {
 226     ui::LayerAnimationSequence* sequence = new ui::LayerAnimationSequence(
 227         ui::LayerAnimationElement::CreateOpacityElement(
 228             1.0, base::TimeDelta()));
 229     sequence->AddObserver(observer);
 230     layer->GetAnimator()->ScheduleAnimation(sequence);
 231   }
 232 }
 233
 234 void ShowWindow(aura::Window* window,
 235                 base::TimeDelta duration,
 236                 bool above,
 237                 ui::LayerAnimationObserver* observer) {
 238   ui::Layer* layer = window->layer();
 239   ui::ScopedLayerAnimationSettings settings(layer->GetAnimator());
 240
 241   // Set initial state of animation
 242   settings.SetPreemptionStrategy(
 243       ui::LayerAnimator::IMMEDIATELY_ANIMATE_TO_NEW_TARGET);
 244   settings.SetTransitionDuration(base::TimeDelta());
 245   SetTransformForScaleAnimation(layer,
 246       above ? LAYER_SCALE_ANIMATION_ABOVE : LAYER_SCALE_ANIMATION_BELOW);
 247
 248   TransformWindowToBaseState(window, duration, observer);
 249 }
 250
 251 // Starts grayscale/brightness animation for |window| over |duration|. Target
 252 // value for both grayscale and brightness are specified by |target|.
 253 void StartGrayscaleBrightnessAnimationForWindow(
 254     aura::Window* window,
 255     float target,
 256     base::TimeDelta duration,
 257     gfx::Tween::Type tween_type,
 258     ui::LayerAnimationObserver* observer) {
 259   ui::LayerAnimator* animator = window->layer()->GetAnimator();
 260
 261   scoped_ptr<ui::LayerAnimationSequence> brightness_sequence(
 262       new ui::LayerAnimationSequence());
 263   scoped_ptr<ui::LayerAnimationSequence> grayscale_sequence(
 264       new ui::LayerAnimationSequence());
 265
 266   scoped_ptr<ui::LayerAnimationElement> brightness_element(
 267       ui::LayerAnimationElement::CreateBrightnessElement(
 268           target, duration));
 269   brightness_element->set_tween_type(tween_type);
 270   brightness_sequence->AddElement(brightness_element.release());
 271
 272   scoped_ptr<ui::LayerAnimationElement> grayscale_element(
 273       ui::LayerAnimationElement::CreateGrayscaleElement(
 274           target, duration));
 275   grayscale_element->set_tween_type(tween_type);
 276   grayscale_sequence->AddElement(grayscale_element.release());
 277
 278   std::vector<ui::LayerAnimationSequence*> animations;
 279   animations.push_back(brightness_sequence.release());
 280   animations.push_back(grayscale_sequence.release());
 281
 282   if (observer)
 283     animations[0]->AddObserver(observer);
 284
 285   animator->set_preemption_strategy(
 286       ui::LayerAnimator::IMMEDIATELY_ANIMATE_TO_NEW_TARGET);
 287
 288   animator->StartTogether(animations);
 289 }
 290
 291 // Animation observer that will drop animated foreground once animation is
 292 // finished. It is used in when undoing shutdown animation.
 293 class CallbackAnimationObserver : public ui::LayerAnimationObserver {
 294  public:
 295   explicit CallbackAnimationObserver(base::Closure callback)
 296       : callback_(callback) {
 297   }
 298   ~CallbackAnimationObserver() override {}
 299
 300  private:
 301   // Overridden from ui::LayerAnimationObserver:
 302   void OnLayerAnimationEnded(ui::LayerAnimationSequence* seq) override {
 303     // Drop foreground once animation is over.
 304     callback_.Run();
 305     delete this;
 306   }
 307
 308   void OnLayerAnimationAborted(ui::LayerAnimationSequence* seq) override {
 309     // Drop foreground once animation is over.
 310     callback_.Run();
 311     delete this;
 312   }
 313
 314   void OnLayerAnimationScheduled(ui::LayerAnimationSequence* seq) override {}
 315
 316   base::Closure callback_;
 317
 318   DISALLOW_COPY_AND_ASSIGN(CallbackAnimationObserver);
 319 };
 320
 321
 322 bool IsLayerAnimated(ui::Layer* layer,
 323                      SessionStateAnimator::AnimationType type) {
 324   switch (type) {
 325     case SessionStateAnimator::ANIMATION_PARTIAL_CLOSE:
 326       if (layer->GetTargetTransform() != GetSlowCloseTransform())
 327         return false;
 328       break;
 329     case SessionStateAnimator::ANIMATION_UNDO_PARTIAL_CLOSE:
 330       if (layer->GetTargetTransform() != gfx::Transform())
 331         return false;
 332       break;
 333     case SessionStateAnimator::ANIMATION_FULL_CLOSE:
 334       if (layer->GetTargetTransform() != GetFastCloseTransform() ||
 335           layer->GetTargetOpacity() > 0.0001)
 336         return false;
 337       break;
 338     case SessionStateAnimator::ANIMATION_FADE_IN:
 339       if (layer->GetTargetOpacity() < 0.9999)
 340         return false;
 341       break;
 342     case SessionStateAnimator::ANIMATION_FADE_OUT:
 343       if (layer->GetTargetOpacity() > 0.0001)
 344         return false;
 345       break;
 346     case SessionStateAnimator::ANIMATION_HIDE_IMMEDIATELY:
 347       if (layer->GetTargetOpacity() > 0.0001)
 348         return false;
 349       break;
 350     case SessionStateAnimator::ANIMATION_RESTORE:
 351       if (layer->opacity() < 0.9999 || layer->transform() != gfx::Transform())
 352         return false;
 353       break;
 354     case SessionStateAnimator::ANIMATION_GRAYSCALE_BRIGHTNESS:
 355       if ((layer->GetTargetBrightness() < 0.9999) ||
 356           (layer->GetTargetGrayscale() < 0.9999))
 357         return false;
 358       break;
 359     case SessionStateAnimator::ANIMATION_UNDO_GRAYSCALE_BRIGHTNESS:
 360       if ((layer->GetTargetBrightness() > 0.0001) ||
 361           (layer->GetTargetGrayscale() > 0.0001))
 362         return false;
 363       break;
 364     case SessionStateAnimator::ANIMATION_DROP:
 365     case SessionStateAnimator::ANIMATION_UNDO_LIFT:
 366       //ToDo(antim) : check other effects
 367       if (layer->GetTargetOpacity() < 0.9999)
 368         return false;
 369       break;
 370       //ToDo(antim) : check other effects
 371     case SessionStateAnimator::ANIMATION_LIFT:
 372       if (layer->GetTargetOpacity() > 0.0001)
 373         return false;
 374       break;
 375     case SessionStateAnimator::ANIMATION_RAISE_TO_SCREEN:
 376       //ToDo(antim) : check other effects
 377       if (layer->GetTargetOpacity() < 0.9999)
 378         return false;
 379       break;
 380       //ToDo(antim) : check other effects
 381     case SessionStateAnimator::ANIMATION_LOWER_BELOW_SCREEN:
 382       if (layer->GetTargetOpacity() > 0.0001)
 383         return false;
 384       break;
 385     default:
 386       NOTREACHED() << "Unhandled animation type " << type;
 387       return false;
 388   }
 389   return true;
 390 }
 391
 392 }  // namespace
 393
 394 // This observer is intended to use in cases when some action has to be taken
 395 // once some animation successfully completes (i.e. it was not aborted).
 396 // Observer will count a number of sequences it is attached to, and a number of
 397 // finished sequences (either Ended or Aborted). Once these two numbers are
 398 // equal, observer will delete itself, calling callback passed to constructor if
 399 // there were no aborted animations.
 400 // This way it can be either used to wait for some animation to be finished in
 401 // multiple layers, to wait once a sequence of animations is finished in one
 402 // layer or the mixture of both.
 403 class SessionStateAnimatorImpl::AnimationSequence
 404   : public SessionStateAnimator::AnimationSequence,
 405     public ui::LayerAnimationObserver {
 406  public:
 407   explicit AnimationSequence(
 408       SessionStateAnimatorImpl* animator,
 409       base::Closure callback)
 410       : SessionStateAnimator::AnimationSequence(callback),
 411         animator_(animator),
 412         sequences_attached_(0),
 413         sequences_completed_(0) {
 414   }
 415
 416   // SessionStateAnimator::AnimationSequence:
 417   void StartAnimation(int container_mask,
 418                       SessionStateAnimator::AnimationType type,
 419                       SessionStateAnimator::AnimationSpeed speed) override {
 420     animator_->StartAnimationInSequence(container_mask, type, speed, this);
 421   }
 422
 423  private:
 424   ~AnimationSequence() override {}
 425
 426   // ui::LayerAnimationObserver:
 427   void OnLayerAnimationEnded(ui::LayerAnimationSequence* sequence) override {
 428     sequences_completed_++;
 429     if (sequences_completed_ == sequences_attached_)
 430       OnAnimationCompleted();
 431   }
 432
 433   void OnLayerAnimationAborted(ui::LayerAnimationSequence* sequence) override {
 434     sequences_completed_++;
 435     if (sequences_completed_ == sequences_attached_)
 436       OnAnimationAborted();
 437   }
 438
 439   void OnLayerAnimationScheduled(
 440       ui::LayerAnimationSequence* sequence) override {}
 441
 442   void OnAttachedToSequence(ui::LayerAnimationSequence* sequence) override {
 443     LayerAnimationObserver::OnAttachedToSequence(sequence);
 444     sequences_attached_++;
 445   }
 446
 447   SessionStateAnimatorImpl* animator_;  // not owned
 448
 449   // Number of sequences this observer was attached to.
 450   int sequences_attached_;
 451
 452   // Number of sequences either ended or aborted.
 453   int sequences_completed_;
 454
 455   DISALLOW_COPY_AND_ASSIGN(AnimationSequence);
 456 };
 457
 458 bool SessionStateAnimatorImpl::TestApi::ContainersAreAnimated(
 459     int container_mask, AnimationType type) const {
 460   aura::Window::Windows containers;
 461   animator_->GetContainers(container_mask, &containers);
 462   for (aura::Window::Windows::const_iterator it = containers.begin();
 463        it != containers.end(); ++it) {
 464     aura::Window* window = *it;
 465     ui::Layer* layer = window->layer();
 466     if (!IsLayerAnimated(layer, type))
 467       return false;
 468   }
 469   return true;
 470 }
 471
 472 bool SessionStateAnimatorImpl::TestApi::RootWindowIsAnimated(AnimationType type)
 473     const {
 474   aura::Window* root_window = Shell::GetPrimaryRootWindow();
 475   ui::Layer* layer = root_window->layer();
 476   return IsLayerAnimated(layer, type);
 477 }
 478
 479 SessionStateAnimatorImpl::SessionStateAnimatorImpl() {
 480 }
 481
 482 SessionStateAnimatorImpl::~SessionStateAnimatorImpl() {
 483 }
 484
 485 // Fills |containers| with the containers described by |container_mask|.
 486 void SessionStateAnimatorImpl::GetContainers(int container_mask,
 487     aura::Window::Windows* containers) {
 488   aura::Window* root_window = Shell::GetPrimaryRootWindow();
 489   containers->clear();
 490
 491   if (container_mask & ROOT_CONTAINER) {
 492     containers->push_back(Shell::GetPrimaryRootWindow());
 493   }
 494
 495   if (container_mask & DESKTOP_BACKGROUND) {
 496     containers->push_back(Shell::GetContainer(
 497         root_window, kShellWindowId_DesktopBackgroundContainer));
 498   }
 499   if (container_mask & LAUNCHER) {
 500     containers->push_back(
 501         Shell::GetContainer(root_window, kShellWindowId_ShelfContainer));
 502   }
 503   if (container_mask & NON_LOCK_SCREEN_CONTAINERS) {
 504     // TODO(antrim): Figure out a way to eliminate a need to exclude launcher
 505     // in such way.
 506     aura::Window* non_lock_screen_containers = Shell::GetContainer(
 507         root_window, kShellWindowId_NonLockScreenContainersContainer);
 508     aura::Window::Windows children = non_lock_screen_containers->children();
 509
 510     for (aura::Window::Windows::const_iterator it = children.begin();
 511          it != children.end(); ++it) {
 512       aura::Window* window = *it;
 513       if (window->id() == kShellWindowId_ShelfContainer)
 514         continue;
 515       containers->push_back(window);
 516     }
 517   }
 518   if (container_mask & LOCK_SCREEN_BACKGROUND) {
 519     containers->push_back(Shell::GetContainer(
 520         root_window, kShellWindowId_LockScreenBackgroundContainer));
 521   }
 522   if (container_mask & LOCK_SCREEN_CONTAINERS) {
 523     containers->push_back(Shell::GetContainer(
 524         root_window, kShellWindowId_LockScreenContainersContainer));
 525   }
 526   if (container_mask & LOCK_SCREEN_RELATED_CONTAINERS) {
 527     containers->push_back(Shell::GetContainer(
 528         root_window, kShellWindowId_LockScreenRelatedContainersContainer));
 529   }
 530 }
 531
 532 void SessionStateAnimatorImpl::StartAnimation(int container_mask,
 533                                               AnimationType type,
 534                                               AnimationSpeed speed) {
 535   aura::Window::Windows containers;
 536   GetContainers(container_mask, &containers);
 537   for (aura::Window::Windows::const_iterator it = containers.begin();
 538        it != containers.end(); ++it) {
 539     RunAnimationForWindow(*it, type, speed, NULL);
 540   }
 541 }
 542
 543 void SessionStateAnimatorImpl::StartAnimationWithCallback(
 544     int container_mask,
 545     AnimationType type,
 546     AnimationSpeed speed,
 547     base::Closure callback) {
 548   aura::Window::Windows containers;
 549   GetContainers(container_mask, &containers);
 550   for (aura::Window::Windows::const_iterator it = containers.begin();
 551        it != containers.end(); ++it) {
 552     ui::LayerAnimationObserver* observer =
 553         new CallbackAnimationObserver(callback);
 554     RunAnimationForWindow(*it, type, speed, observer);
 555   }
 556 }
 557
 558 SessionStateAnimator::AnimationSequence*
 559     SessionStateAnimatorImpl::BeginAnimationSequence(base::Closure callback) {
 560   return new AnimationSequence(this, callback);
 561 }
 562
 563 bool SessionStateAnimatorImpl::IsBackgroundHidden() const {
 564   return !GetBackground()->IsVisible();
 565 }
 566
 567 void SessionStateAnimatorImpl::ShowBackground() {
 568   ui::ScopedLayerAnimationSettings settings(
 569       GetBackground()->layer()->GetAnimator());
 570   settings.SetTransitionDuration(base::TimeDelta());
 571   GetBackground()->Show();
 572 }
 573
 574 void SessionStateAnimatorImpl::HideBackground() {
 575   ui::ScopedLayerAnimationSettings settings(
 576       GetBackground()->layer()->GetAnimator());
 577   settings.SetTransitionDuration(base::TimeDelta());
 578   GetBackground()->Hide();
 579 }
 580
 581 void SessionStateAnimatorImpl::StartAnimationInSequence(
 582     int container_mask,
 583     AnimationType type,
 584     AnimationSpeed speed,
 585     AnimationSequence* observer) {
 586   aura::Window::Windows containers;
 587   GetContainers(container_mask, &containers);
 588   for (aura::Window::Windows::const_iterator it = containers.begin();
 589        it != containers.end(); ++it) {
 590     RunAnimationForWindow(*it, type, speed, observer);
 591   }
 592 }
 593
 594 void SessionStateAnimatorImpl::RunAnimationForWindow(
 595     aura::Window* window,
 596     AnimationType type,
 597     AnimationSpeed speed,
 598     ui::LayerAnimationObserver* observer) {
 599   base::TimeDelta duration = GetDuration(speed);
 600
 601   switch (type) {
 602     case ANIMATION_PARTIAL_CLOSE:
 603       StartSlowCloseAnimationForWindow(window, duration, observer);
 604       break;
 605     case ANIMATION_UNDO_PARTIAL_CLOSE:
 606       StartUndoSlowCloseAnimationForWindow(window, duration, observer);
 607       break;
 608     case ANIMATION_FULL_CLOSE:
 609       StartFastCloseAnimationForWindow(window, duration, observer);
 610       break;
 611     case ANIMATION_FADE_IN:
 612       StartOpacityAnimationForWindow(window, 1.0, duration, observer);
 613       break;
 614     case ANIMATION_FADE_OUT:
 615       StartOpacityAnimationForWindow(window, 0.0, duration, observer);
 616       break;
 617     case ANIMATION_HIDE_IMMEDIATELY:
 618       DCHECK_EQ(speed, ANIMATION_SPEED_IMMEDIATE);
 619       HideWindowImmediately(window, observer);
 620       break;
 621     case ANIMATION_RESTORE:
 622       DCHECK_EQ(speed, ANIMATION_SPEED_IMMEDIATE);
 623       RestoreWindow(window, observer);
 624       break;
 625     case ANIMATION_LIFT:
 626       HideWindow(window, duration, true, observer);
 627       break;
 628     case ANIMATION_DROP:
 629       ShowWindow(window, duration, true, observer);
 630       break;
 631     case ANIMATION_UNDO_LIFT:
 632       TransformWindowToBaseState(window, duration, observer);
 633       break;
 634     case ANIMATION_RAISE_TO_SCREEN:
 635       ShowWindow(window, duration, false, observer);
 636       break;
 637     case ANIMATION_LOWER_BELOW_SCREEN:
 638       HideWindow(window, duration, false, observer);
 639       break;
 640     case ANIMATION_PARTIAL_FADE_IN:
 641       StartPartialFadeAnimation(
 642           window, kPartialFadeRatio, duration, observer);
 643       break;
 644     case ANIMATION_UNDO_PARTIAL_FADE_IN:
 645       StartPartialFadeAnimation(window, 0.0, duration, observer);
 646       break;
 647     case ANIMATION_FULL_FADE_IN:
 648       StartPartialFadeAnimation(window, 1.0, duration, observer);
 649       break;
 650     case ANIMATION_GRAYSCALE_BRIGHTNESS:
 651       StartGrayscaleBrightnessAnimationForWindow(
 652           window, 1.0, duration, gfx::Tween::EASE_IN, observer);
 653       break;
 654     case ANIMATION_UNDO_GRAYSCALE_BRIGHTNESS:
 655       StartGrayscaleBrightnessAnimationForWindow(
 656           window, 0.0, duration, gfx::Tween::EASE_IN_OUT, observer);
 657       break;
 658   }
 659 }
 660
 661 }  // namespace ash