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