gecko-dev/dom/svg/DOMSVGTransformList.h

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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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 DOM_SVG_DOMSVGTRANSFORMLIST_H_
#define DOM_SVG_DOMSVGTRANSFORMLIST_H_
#include "DOMSVGAnimatedTransformList.h"
#include "mozAutoDocUpdate.h"
#include "nsCycleCollectionParticipant.h"
#include "nsDebug.h"
#include "SVGTransformList.h"
#include "nsTArray.h"
#include "mozilla/Attributes.h"
namespace mozilla {
class ErrorResult;
namespace dom {
struct DOMMatrix2DInit;
class DOMSVGTransform;
class SVGElement;
class SVGMatrix;
//----------------------------------------------------------------------
// Helper class: AutoChangeTransformListNotifier
// Stack-based helper class to pair calls to WillChangeTransformList and
// DidChangeTransformList. Used by DOMSVGTransform and DOMSVGTransformList.
template <class T>
class MOZ_RAII AutoChangeTransformListNotifier {
public:
explicit AutoChangeTransformListNotifier(T* aValue) : mValue(aValue) {
MOZ_ASSERT(mValue, "Expecting non-null value");
// If we don't have an owner then changes don't affect anything else.
if (mValue->HasOwner()) {
mUpdateBatch.emplace(mValue->Element()->GetComposedDoc(), true);
mEmptyOrOldValue =
mValue->Element()->WillChangeTransformList(mUpdateBatch.ref());
}
}
~AutoChangeTransformListNotifier() {
if (mValue->HasOwner()) {
mValue->Element()->DidChangeTransformList(mEmptyOrOldValue,
mUpdateBatch.ref());
if (mValue->IsAnimating()) {
mValue->Element()->AnimationNeedsResample();
}
}
}
private:
T* const mValue;
Maybe<mozAutoDocUpdate> mUpdateBatch;
nsAttrValue mEmptyOrOldValue;
};
/**
* Class DOMSVGTransformList
*
* This class is used to create the DOM tearoff objects that wrap internal
* SVGTransformList objects.
*
* See the architecture comment in DOMSVGAnimatedTransformList.h.
*/
class DOMSVGTransformList final : public nsISupports, public nsWrapperCache {
template <class T>
friend class AutoChangeTransformListNotifier;
friend class dom::DOMSVGTransform;
~DOMSVGTransformList() {
// Our mAList's weak ref to us must be nulled out when we die. If GC has
// unlinked us using the cycle collector code, then that has already
// happened, and mAList is null.
if (mAList) {
(IsAnimValList() ? mAList->mAnimVal : mAList->mBaseVal) = nullptr;
}
}
public:
NS_DECL_CYCLE_COLLECTING_ISUPPORTS
NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS(DOMSVGTransformList)
DOMSVGTransformList(dom::DOMSVGAnimatedTransformList* aAList,
const SVGTransformList& aInternalList)
: mAList(aAList) {
// aInternalList must be passed in explicitly because we can't use
// InternalList() here. (Because it depends on IsAnimValList, which depends
// on this object having been assigned to aAList's mBaseVal or mAnimVal,
// which hasn't happened yet.)
InternalListLengthWillChange(aInternalList.Length()); // Sync mItems
}
JSObject* WrapObject(JSContext* cx,
JS::Handle<JSObject*> aGivenProto) override;
nsISupports* GetParentObject() { return static_cast<nsIContent*>(Element()); }
/**
* This will normally be the same as InternalList().Length(), except if we've
* hit OOM in which case our length will be zero.
*/
uint32_t LengthNoFlush() const {
MOZ_ASSERT(mItems.IsEmpty() || mItems.Length() == InternalList().Length(),
"DOM wrapper's list length is out of sync");
return mItems.Length();
}
/// Called to notify us to synchronize our length and detach excess items.
void InternalListLengthWillChange(uint32_t aNewLength);
/*
* List classes always have an owner. We need this so that templates that work
* on lists and elements can check ownership where elements may be unowned.
*/
bool HasOwner() const { return true; }
/**
* Returns true if our attribute is animating (in which case our animVal is
* not simply a mirror of our baseVal).
*/
bool IsAnimating() const { return mAList->IsAnimating(); }
/**
* Returns true if there is an animated list mirroring the base list.
*/
bool AnimListMirrorsBaseList() const {
return mAList->mAnimVal && !mAList->IsAnimating();
}
uint32_t NumberOfItems() const {
if (IsAnimValList()) {
Element()->FlushAnimations();
}
return LengthNoFlush();
}
void Clear(ErrorResult& error);
already_AddRefed<dom::DOMSVGTransform> Initialize(
dom::DOMSVGTransform& newItem, ErrorResult& error);
already_AddRefed<dom::DOMSVGTransform> GetItem(uint32_t index,
ErrorResult& error);
already_AddRefed<dom::DOMSVGTransform> IndexedGetter(uint32_t index,
bool& found,
ErrorResult& error);
already_AddRefed<dom::DOMSVGTransform> InsertItemBefore(
dom::DOMSVGTransform& newItem, uint32_t index, ErrorResult& error);
already_AddRefed<dom::DOMSVGTransform> ReplaceItem(
dom::DOMSVGTransform& newItem, uint32_t index, ErrorResult& error);
already_AddRefed<dom::DOMSVGTransform> RemoveItem(uint32_t index,
ErrorResult& error);
already_AddRefed<dom::DOMSVGTransform> AppendItem(
dom::DOMSVGTransform& newItem, ErrorResult& error) {
return InsertItemBefore(newItem, LengthNoFlush(), error);
}
already_AddRefed<dom::DOMSVGTransform> CreateSVGTransformFromMatrix(
const DOMMatrix2DInit& aMatrix, ErrorResult& aRv);
already_AddRefed<dom::DOMSVGTransform> Consolidate(ErrorResult& error);
uint32_t Length() const { return NumberOfItems(); }
private:
dom::SVGElement* Element() const { return mAList->mElement; }
/// Used to determine if this list is the baseVal or animVal list.
bool IsAnimValList() const {
MOZ_ASSERT(this == mAList->mBaseVal || this == mAList->mAnimVal,
"Calling IsAnimValList() too early?!");
return this == mAList->mAnimVal;
}
/**
* Get a reference to this object's corresponding internal SVGTransformList.
*
* To simplify the code we just have this one method for obtaining both
* baseVal and animVal internal lists. This means that animVal lists don't
* get const protection, but our setter methods guard against changing
* animVal lists.
*/
SVGTransformList& InternalList() const;
/// Returns the DOMSVGTransform at aIndex, creating it if necessary.
already_AddRefed<dom::DOMSVGTransform> GetItemAt(uint32_t aIndex);
void MaybeInsertNullInAnimValListAt(uint32_t aIndex);
void MaybeRemoveItemFromAnimValListAt(uint32_t aIndex);
// Weak refs to our DOMSVGTransform items. The items are friends and take care
// of clearing our pointer to them when they die.
FallibleTArray<dom::DOMSVGTransform*> mItems;
RefPtr<dom::DOMSVGAnimatedTransformList> mAList;
};
} // namespace dom
} // namespace mozilla
#endif // DOM_SVG_DOMSVGTRANSFORMLIST_H_