gecko-dev/layout/style/AnimationCommon.h
2016-05-10 18:39:37 +09:00

257 lines
7.1 KiB
C++

/* vim: set shiftwidth=2 tabstop=8 autoindent cindent expandtab: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef mozilla_css_AnimationCommon_h
#define mozilla_css_AnimationCommon_h
#include <algorithm> // For <std::stable_sort>
#include "mozilla/AnimationCollection.h"
#include "mozilla/AnimationComparator.h"
#include "mozilla/EventDispatcher.h"
#include "mozilla/LinkedList.h"
#include "mozilla/MemoryReporting.h"
#include "mozilla/dom/Animation.h"
#include "mozilla/Attributes.h" // For MOZ_NON_OWNING_REF
#include "mozilla/Assertions.h"
#include "nsContentUtils.h"
#include "nsCSSPseudoElements.h"
#include "nsCycleCollectionParticipant.h"
class nsIFrame;
class nsPresContext;
namespace mozilla {
namespace dom {
class Element;
}
template <class AnimationType>
class CommonAnimationManager {
public:
explicit CommonAnimationManager(nsPresContext *aPresContext)
: mPresContext(aPresContext)
{
}
// NOTE: This can return null after Disconnect().
nsPresContext* PresContext() const { return mPresContext; }
/**
* Notify the manager that the pres context is going away.
*/
void Disconnect()
{
// Content nodes might outlive the transition or animation manager.
RemoveAllElementCollections();
mPresContext = nullptr;
}
protected:
virtual ~CommonAnimationManager()
{
MOZ_ASSERT(!mPresContext, "Disconnect should have been called");
}
void AddElementCollection(AnimationCollection<AnimationType>* aCollection)
{
mElementCollections.insertBack(aCollection);
}
void RemoveAllElementCollections()
{
while (AnimationCollection<AnimationType>* head =
mElementCollections.getFirst()) {
head->Destroy(); // Note: this removes 'head' from mElementCollections.
}
}
LinkedList<AnimationCollection<AnimationType>> mElementCollections;
nsPresContext *mPresContext; // weak (non-null from ctor to Disconnect)
};
/**
* Utility class for referencing the element that created a CSS animation or
* transition. It is non-owning (i.e. it uses a raw pointer) since it is only
* expected to be set by the owned animation while it actually being managed
* by the owning element.
*
* This class also abstracts the comparison of an element/pseudo-class pair
* for the sake of composite ordering since this logic is common to both CSS
* animations and transitions.
*
* (We call this OwningElementRef instead of just OwningElement so that we can
* call the getter on CSSAnimation/CSSTransition OwningElement() without
* clashing with this object's contructor.)
*/
class OwningElementRef final
{
public:
OwningElementRef()
: mElement(nullptr)
, mPseudoType(CSSPseudoElementType::NotPseudo)
{ }
OwningElementRef(dom::Element& aElement,
CSSPseudoElementType aPseudoType)
: mElement(&aElement)
, mPseudoType(aPseudoType)
{ }
bool Equals(const OwningElementRef& aOther) const
{
return mElement == aOther.mElement &&
mPseudoType == aOther.mPseudoType;
}
bool LessThan(const OwningElementRef& aOther) const
{
MOZ_ASSERT(mElement && aOther.mElement,
"Elements to compare should not be null");
if (mElement != aOther.mElement) {
return nsContentUtils::PositionIsBefore(mElement, aOther.mElement);
}
return mPseudoType == CSSPseudoElementType::NotPseudo ||
(mPseudoType == CSSPseudoElementType::before &&
aOther.mPseudoType == CSSPseudoElementType::after);
}
bool IsSet() const { return !!mElement; }
void GetElement(dom::Element*& aElement,
CSSPseudoElementType& aPseudoType) const {
aElement = mElement;
aPseudoType = mPseudoType;
}
nsPresContext* GetRenderedPresContext() const;
private:
dom::Element* MOZ_NON_OWNING_REF mElement;
CSSPseudoElementType mPseudoType;
};
template <class EventInfo>
class DelayedEventDispatcher
{
public:
DelayedEventDispatcher() : mIsSorted(true) { }
void QueueEvent(EventInfo&& aEventInfo)
{
mPendingEvents.AppendElement(Forward<EventInfo>(aEventInfo));
mIsSorted = false;
}
// This is exposed as a separate method so that when we are dispatching
// *both* transition events and animation events we can sort both lists
// once using the current state of the document before beginning any
// dispatch.
void SortEvents()
{
if (mIsSorted) {
return;
}
// FIXME: Replace with mPendingEvents.StableSort when bug 1147091 is
// fixed.
std::stable_sort(mPendingEvents.begin(), mPendingEvents.end(),
EventInfoLessThan());
mIsSorted = true;
}
// Takes a reference to the owning manager's pres context so it can
// detect if the pres context is destroyed while dispatching one of
// the events.
//
// This will call SortEvents automatically if it has not already been
// called.
void DispatchEvents(nsPresContext* const & aPresContext)
{
if (!aPresContext || mPendingEvents.IsEmpty()) {
return;
}
SortEvents();
EventArray events;
mPendingEvents.SwapElements(events);
// mIsSorted will be set to true by SortEvents above, and we leave it
// that way since mPendingEvents is now empty
for (EventInfo& info : events) {
EventDispatcher::Dispatch(info.mElement, aPresContext, &info.mEvent);
if (!aPresContext) {
break;
}
}
}
void ClearEventQueue()
{
mPendingEvents.Clear();
mIsSorted = true;
}
bool HasQueuedEvents() const { return !mPendingEvents.IsEmpty(); }
// Methods for supporting cycle-collection
void Traverse(nsCycleCollectionTraversalCallback* aCallback,
const char* aName)
{
for (EventInfo& info : mPendingEvents) {
ImplCycleCollectionTraverse(*aCallback, info.mElement, aName);
ImplCycleCollectionTraverse(*aCallback, info.mAnimation, aName);
}
}
void Unlink() { ClearEventQueue(); }
protected:
class EventInfoLessThan
{
public:
bool operator()(const EventInfo& a, const EventInfo& b) const
{
if (a.mTimeStamp != b.mTimeStamp) {
// Null timestamps sort first
if (a.mTimeStamp.IsNull() || b.mTimeStamp.IsNull()) {
return a.mTimeStamp.IsNull();
} else {
return a.mTimeStamp < b.mTimeStamp;
}
}
AnimationPtrComparator<RefPtr<dom::Animation>> comparator;
return comparator.LessThan(a.mAnimation, b.mAnimation);
}
};
typedef nsTArray<EventInfo> EventArray;
EventArray mPendingEvents;
bool mIsSorted;
};
template <class EventInfo>
inline void
ImplCycleCollectionUnlink(DelayedEventDispatcher<EventInfo>& aField)
{
aField.Unlink();
}
template <class EventInfo>
inline void
ImplCycleCollectionTraverse(nsCycleCollectionTraversalCallback& aCallback,
DelayedEventDispatcher<EventInfo>& aField,
const char* aName,
uint32_t aFlags = 0)
{
aField.Traverse(&aCallback, aName);
}
} // namespace mozilla
#endif /* !defined(mozilla_css_AnimationCommon_h) */