ui/compositor/layer_animator_collection.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/compositor/layer_animator_collection.h"
   6
   7 #include <set>
   8
   9 #include "base/time/time.h"
  10 #include "ui/compositor/compositor.h"
  11 #include "ui/compositor/layer_animator.h"
  12
  13 namespace ui {
  14
  15 LayerAnimatorCollection::LayerAnimatorCollection(Compositor* compositor)
  16     : compositor_(compositor), last_tick_time_(base::TimeTicks::Now()) {
  17 }
  18
  19 LayerAnimatorCollection::~LayerAnimatorCollection() {
  20   if (compositor_)
  21     compositor_->RemoveAnimationObserver(this);
  22 }
  23
  24 void LayerAnimatorCollection::StartAnimator(
  25     scoped_refptr<LayerAnimator> animator) {
  26   DCHECK_EQ(0U, animators_.count(animator));
  27   if (!animators_.size())
  28     last_tick_time_ = base::TimeTicks::Now();
  29   animators_.insert(animator);
  30   if (animators_.size() == 1U && compositor_)
  31     compositor_->AddAnimationObserver(this);
  32 }
  33
  34 void LayerAnimatorCollection::StopAnimator(
  35     scoped_refptr<LayerAnimator> animator) {
  36   DCHECK_GT(animators_.count(animator), 0U);
  37   animators_.erase(animator);
  38   if (animators_.empty() && compositor_)
  39     compositor_->RemoveAnimationObserver(this);
  40 }
  41
  42 bool LayerAnimatorCollection::HasActiveAnimators() const {
  43   return !animators_.empty();
  44 }
  45
  46 void LayerAnimatorCollection::OnAnimationStep(base::TimeTicks now) {
  47   last_tick_time_ = now;
  48   std::set<scoped_refptr<LayerAnimator> > list = animators_;
  49   for (std::set<scoped_refptr<LayerAnimator> >::iterator iter = list.begin();
  50        iter != list.end();
  51        ++iter) {
  52     // Make sure the animator is still valid.
  53     if (animators_.count(*iter) > 0)
  54       (*iter)->Step(now);
  55   }
  56   if (!HasActiveAnimators() && compositor_)
  57     compositor_->RemoveAnimationObserver(this);
  58 }
  59
  60 void LayerAnimatorCollection::OnCompositingShuttingDown(
  61     Compositor* compositor) {
  62   DCHECK_EQ(compositor_, compositor);
  63   compositor_->RemoveAnimationObserver(this);
  64   compositor_ = nullptr;
  65 }
  66
  67 }  // namespace ui