diff options
Diffstat (limited to 'dom/svg/DOMSVGNumberList.h')
| -rw-r--r-- | dom/svg/DOMSVGNumberList.h | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/dom/svg/DOMSVGNumberList.h b/dom/svg/DOMSVGNumberList.h new file mode 100644 index 0000000000..0e36d30ba3 --- /dev/null +++ b/dom/svg/DOMSVGNumberList.h @@ -0,0 +1,194 @@ +/* -*- 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_DOMSVGNUMBERLIST_H_ +#define DOM_SVG_DOMSVGNUMBERLIST_H_ + +#include "DOMSVGAnimatedNumberList.h" +#include "mozAutoDocUpdate.h" +#include "nsCycleCollectionParticipant.h" +#include "nsDebug.h" +#include "nsTArray.h" +#include "SVGNumberList.h" +#include "mozilla/Attributes.h" +#include "mozilla/RefPtr.h" + +namespace mozilla { +class ErrorResult; + +namespace dom { +class DOMSVGNumber; +class SVGElement; + +//---------------------------------------------------------------------- +// Helper class: AutoChangeNumberListNotifier +// Stack-based helper class to pair calls to WillChangeNumberList and +// DidChangeNumberList. Used by DOMSVGNumber and DOMSVGNumberList. +template <class T> +class MOZ_RAII AutoChangeNumberListNotifier : public mozAutoDocUpdate { + public: + explicit AutoChangeNumberListNotifier(T* aValue) + : mozAutoDocUpdate(aValue->Element()->GetComposedDoc(), true), + mValue(aValue) { + MOZ_ASSERT(mValue, "Expecting non-null value"); + mEmptyOrOldValue = + mValue->Element()->WillChangeNumberList(mValue->AttrEnum(), *this); + } + + ~AutoChangeNumberListNotifier() { + mValue->Element()->DidChangeNumberList(mValue->AttrEnum(), mEmptyOrOldValue, + *this); + if (mValue->IsAnimating()) { + mValue->Element()->AnimationNeedsResample(); + } + } + + private: + T* const mValue; + nsAttrValue mEmptyOrOldValue; +}; + +/** + * Class DOMSVGNumberList + * + * This class is used to create the DOM tearoff objects that wrap internal + * SVGNumberList objects. + * + * See the architecture comment in DOMSVGAnimatedNumberList.h. + * + * This class is strongly intertwined with DOMSVGAnimatedNumberList and + * DOMSVGNumber. We are a friend of DOMSVGAnimatedNumberList, and are + * responsible for nulling out our DOMSVGAnimatedNumberList's pointer to us + * when we die, essentially making its pointer to us a weak pointer. Similarly, + * our DOMSVGNumber items are friends of us and responsible for nulling out our + * pointers to them. + * + * Our DOM items are created lazily on demand as and when script requests them. + */ +class DOMSVGNumberList final : public nsISupports, public nsWrapperCache { + template <class T> + friend class AutoChangeNumberListNotifier; + friend class DOMSVGNumber; + + ~DOMSVGNumberList() { + // 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(DOMSVGNumberList) + + DOMSVGNumberList(DOMSVGAnimatedNumberList* aAList, + const SVGNumberList& 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.Length() == 0 || 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); + + /** + * 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<DOMSVGNumber> Initialize(DOMSVGNumber& aItem, + ErrorResult& error); + already_AddRefed<DOMSVGNumber> GetItem(uint32_t index, ErrorResult& error); + already_AddRefed<DOMSVGNumber> IndexedGetter(uint32_t index, bool& found, + ErrorResult& error); + already_AddRefed<DOMSVGNumber> InsertItemBefore(DOMSVGNumber& aItem, + uint32_t index, + ErrorResult& error); + already_AddRefed<DOMSVGNumber> ReplaceItem(DOMSVGNumber& aItem, + uint32_t index, + ErrorResult& error); + already_AddRefed<DOMSVGNumber> RemoveItem(uint32_t index, ErrorResult& error); + already_AddRefed<DOMSVGNumber> AppendItem(DOMSVGNumber& newItem, + ErrorResult& error) { + return InsertItemBefore(newItem, LengthNoFlush(), error); + } + uint32_t Length() const { return NumberOfItems(); } + + private: + dom::SVGElement* Element() const { return mAList->mElement; } + + uint8_t AttrEnum() const { return mAList->mAttrEnum; } + + /// 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 SVGNumberList. + * + * 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. + */ + SVGNumberList& InternalList() const; + + /// Returns the DOMSVGNumber at aIndex, creating it if necessary. + already_AddRefed<DOMSVGNumber> GetItemAt(uint32_t aIndex); + + void MaybeInsertNullInAnimValListAt(uint32_t aIndex); + void MaybeRemoveItemFromAnimValListAt(uint32_t aIndex); + + // Weak refs to our DOMSVGNumber items. The items are friends and take care + // of clearing our pointer to them when they die. + FallibleTArray<DOMSVGNumber*> mItems; + + RefPtr<DOMSVGAnimatedNumberList> mAList; +}; + +} // namespace dom +} // namespace mozilla + +#endif // DOM_SVG_DOMSVGNUMBERLIST_H_ |