blob: 30fa12887e9eac7cb54a36ffec32998acacdc39d [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 "ui/gfx/animation/animation_container.h"
#include "base/bind.h"
#include "ui/gfx/animation/animation_container_element.h"
#include "ui/gfx/animation/animation_container_observer.h"
using base::TimeDelta;
using base::TimeTicks;
namespace gfx {
AnimationContainer::AnimationContainer() = default;
AnimationContainer::~AnimationContainer() {
// The animations own us and stop themselves before being deleted. If
// elements_ is not empty, something is wrong.
DCHECK(elements_.empty());
}
void AnimationContainer::Start(AnimationContainerElement* element) {
DCHECK(elements_.count(element) == 0); // Start should only be invoked if the
// element isn't running.
if (elements_.empty()) {
last_tick_time_ = base::TimeTicks::Now();
SetMinTimerInterval(element->GetTimerInterval());
min_timer_interval_count_ = 1;
} else if (element->GetTimerInterval() < min_timer_interval_) {
SetMinTimerInterval(element->GetTimerInterval());
min_timer_interval_count_ = 1;
} else if (element->GetTimerInterval() == min_timer_interval_) {
min_timer_interval_count_++;
}
element->SetStartTime(last_tick_time_);
elements_.insert(element);
}
void AnimationContainer::Stop(AnimationContainerElement* element) {
DCHECK(elements_.count(element) > 0); // The element must be running.
base::TimeDelta interval = element->GetTimerInterval();
elements_.erase(element);
if (elements_.empty()) {
runner_->Stop();
min_timer_interval_count_ = 0;
if (observer_)
observer_->AnimationContainerEmpty(this);
} else if (interval == min_timer_interval_) {
min_timer_interval_count_--;
// If the last element at the current (minimum) timer interval has been
// removed then go find the new minimum and the number of elements at that
// same minimum.
if (min_timer_interval_count_ == 0) {
std::pair<base::TimeDelta, size_t> interval_count =
GetMinIntervalAndCount();
DCHECK(interval_count.first > min_timer_interval_);
SetMinTimerInterval(interval_count.first);
min_timer_interval_count_ = interval_count.second;
}
}
}
void AnimationContainer::SetAnimationRunner(
std::unique_ptr<AnimationRunner> runner) {
has_custom_animation_runner_ = !!runner;
runner_ = has_custom_animation_runner_
? std::move(runner)
: AnimationRunner::CreateDefaultAnimationRunner();
}
void AnimationContainer::Run(base::TimeTicks current_time) {
// We notify the observer after updating all the elements. If all the elements
// are deleted as a result of updating then our ref count would go to zero and
// we would be deleted before we notify our observer. We add a reference to
// ourself here to make sure we're still valid after running all the elements.
scoped_refptr<AnimationContainer> this_ref(this);
last_tick_time_ = current_time;
// Make a copy of the elements to iterate over so that if any elements are
// removed as part of invoking Step there aren't any problems.
Elements elements = elements_;
for (Elements::const_iterator i = elements.begin();
i != elements.end(); ++i) {
// Make sure the element is still valid.
if (elements_.find(*i) != elements_.end())
(*i)->Step(current_time);
}
if (observer_)
observer_->AnimationContainerProgressed(this);
}
void AnimationContainer::SetMinTimerInterval(base::TimeDelta delta) {
// This doesn't take into account how far along the current element is, but
// that shouldn't be a problem for uses of Animation/AnimationContainer.
runner_->Stop();
min_timer_interval_ = delta;
runner_->Start(
min_timer_interval_,
base::BindRepeating(&AnimationContainer::Run, base::Unretained(this)));
}
std::pair<TimeDelta, size_t> AnimationContainer::GetMinIntervalAndCount()
const {
DCHECK(!elements_.empty());
// Find the minimum interval and the number of elements sharing that same
// interval. It is tempting to create a map of intervals -> counts in order to
// make this O(log n) instead of O(n). However, profiling shows that this
// offers no practical performance gain (the most common case is that all
// elements in the set share the same interval).
TimeDelta min;
size_t count = 1;
auto i = elements_.begin();
min = (*i)->GetTimerInterval();
for (++i; i != elements_.end(); ++i) {
auto interval = (*i)->GetTimerInterval();
if (interval < min) {
min = interval;
count = 1;
} else if (interval == min) {
count++;
}
}
return std::make_pair(min, count);
}
} // namespace gfx