blob: 9a0849441b5dfa12cc1be3c926afeb5002ddb4dd [file] [log] [blame]
// Copyright (c) 2011 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include <memory>
#include <utility>
#include "base/containers/flat_set.h"
#include "base/macros.h"
#include "base/memory/ref_counted.h"
#include "base/time/time.h"
#include "ui/gfx/animation/animation_export.h"
#include "ui/gfx/animation/animation_runner.h"
namespace gfx {
class AnimationContainerElement;
class AnimationContainerObserver;
// AnimationContainer is used by Animation to manage the underlying
// AnimationRunner. Internally each Animation creates a single
// AnimationContainer. You can group a set of Animations into the same
// AnimationContainer by way of Animation::SetContainer. Grouping a set of
// Animations into the same AnimationContainer ensures they all update and start
// at the same time.
// AnimationContainer is ref counted. Each Animation contained within the
// AnimationContainer own it.
class ANIMATION_EXPORT AnimationContainer
: public base::RefCounted<AnimationContainer> {
// Invoked by Animation when it needs to start. Starts the timer if necessary.
// NOTE: This is invoked by Animation for you, you shouldn't invoke this
// directly.
void Start(AnimationContainerElement* animation);
// Invoked by Animation when it needs to stop. If there are no more animations
// running the timer stops.
// NOTE: This is invoked by Animation for you, you shouldn't invoke this
// directly.
void Stop(AnimationContainerElement* animation);
void set_observer(AnimationContainerObserver* observer) {
observer_ = observer;
// The time the last animation ran at.
base::TimeTicks last_tick_time() const { return last_tick_time_; }
// Are there any timers running?
bool is_running() const { return !elements_.empty(); }
void SetAnimationRunner(std::unique_ptr<AnimationRunner> runner);
bool has_custom_animation_runner() const {
return has_custom_animation_runner_;
friend class AnimationContainerTestApi;
friend class base::RefCounted<AnimationContainer>;
// This set is usually quite small so a flat_set is the most obvious choice.
// However, in extreme cases this can grow to 100s or even 1000s of elements.
// Since this set is duplicated on every call to 'Run' and indexed very
// frequently the cache locality of the vector is more important than the
// costlier (but rarer) insertion. Profiling shows that flat_set continues to
// perform best in these cases (up to 12x faster than std::set).
typedef base::flat_set<AnimationContainerElement*> Elements;
// Timer callback method.
void Run(base::TimeTicks current_time);
// Sets min_timer_interval_ and restarts the timer.
void SetMinTimerInterval(base::TimeDelta delta);
// Returns the min timer interval of all the timers, and the count of timers
// at that interval.
std::pair<base::TimeDelta, size_t> GetMinIntervalAndCount() const;
// Represents one of two possible values:
// . If only a single animation has been started and the timer hasn't yet
// fired this is the time the animation was added.
// . The time the last animation ran at (::Run was invoked).
base::TimeTicks last_tick_time_ = base::TimeTicks::Now();
// Set of elements (animations) being managed.
Elements elements_;
// Minimum interval the timers run at, plus the number of timers that have
// been seen at that interval. The most common case is for all of the
// animations to run at 60Hz, in which case all of the intervals are the same.
// This acts as a cache of size 1, and when an animation stops and is removed
// it means that the linear scan for the new minimum timer can almost always
// be avoided.
base::TimeDelta min_timer_interval_;
size_t min_timer_interval_count_ = 0;
std::unique_ptr<AnimationRunner> runner_ =
bool has_custom_animation_runner_ = false;
AnimationContainerObserver* observer_ = nullptr;
} // namespace gfx