dom/animation/CSSPseudoElement.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "mozilla/dom/CSSPseudoElement.h"
   8 #include "mozilla/dom/CSSPseudoElementBinding.h"
   9 #include "mozilla/dom/Element.h"
  10 #include "mozilla/dom/KeyframeEffectBinding.h"
  11 #include "mozilla/AnimationComparator.h"
  12
  13 namespace mozilla {
  14 namespace dom {
  15
  16 NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE(CSSPseudoElement, mOriginatingElement)
  17
  18 NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(CSSPseudoElement, AddRef)
  19 NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(CSSPseudoElement, Release)
  20
  21 CSSPseudoElement::CSSPseudoElement(dom::Element* aElement,
  22                                    PseudoStyleType aType)
  23     : mOriginatingElement(aElement), mPseudoType(aType) {
  24   MOZ_ASSERT(aElement);
  25   MOZ_ASSERT(aType == PseudoStyleType::after ||
  26                  aType == PseudoStyleType::before ||
  27                  aType == PseudoStyleType::marker,
  28              "Unexpected Pseudo Type");
  29 }
  30
  31 CSSPseudoElement::~CSSPseudoElement() {
  32   // Element might have been unlinked already, so we have to do null check.
  33   if (mOriginatingElement) {
  34     mOriginatingElement->RemoveProperty(
  35         GetCSSPseudoElementPropertyAtom(mPseudoType));
  36   }
  37 }
  38
  39 ParentObject CSSPseudoElement::GetParentObject() const {
  40   return mOriginatingElement->GetParentObject();
  41 }
  42
  43 JSObject* CSSPseudoElement::WrapObject(JSContext* aCx,
  44                                        JS::Handle<JSObject*> aGivenProto) {
  45   return CSSPseudoElement_Binding::Wrap(aCx, this, aGivenProto);
  46 }
  47
  48 /* static */
  49 already_AddRefed<CSSPseudoElement> CSSPseudoElement::GetCSSPseudoElement(
  50     dom::Element* aElement, PseudoStyleType aType) {
  51   if (!aElement) {
  52     return nullptr;
  53   }
  54
  55   nsAtom* propName = CSSPseudoElement::GetCSSPseudoElementPropertyAtom(aType);
  56   RefPtr<CSSPseudoElement> pseudo =
  57       static_cast<CSSPseudoElement*>(aElement->GetProperty(propName));
  58   if (pseudo) {
  59     return pseudo.forget();
  60   }
  61
  62   // CSSPseudoElement is a purely external interface created on-demand, and
  63   // when all references from script to the pseudo are dropped, we can drop the
  64   // CSSPseudoElement object, so use a non-owning reference from Element to
  65   // CSSPseudoElement.
  66   pseudo = new CSSPseudoElement(aElement, aType);
  67   nsresult rv = aElement->SetProperty(propName, pseudo, nullptr, true);
  68   if (NS_FAILED(rv)) {
  69     NS_WARNING("SetProperty failed");
  70     return nullptr;
  71   }
  72   return pseudo.forget();
  73 }
  74
  75 /* static */
  76 nsAtom* CSSPseudoElement::GetCSSPseudoElementPropertyAtom(
  77     PseudoStyleType aType) {
  78   switch (aType) {
  79     case PseudoStyleType::before:
  80       return nsGkAtoms::cssPseudoElementBeforeProperty;
  81
  82     case PseudoStyleType::after:
  83       return nsGkAtoms::cssPseudoElementAfterProperty;
  84
  85     case PseudoStyleType::marker:
  86       return nsGkAtoms::cssPseudoElementMarkerProperty;
  87
  88     default:
  89       MOZ_ASSERT_UNREACHABLE(
  90           "Should not try to get CSSPseudoElement "
  91           "other than ::before, ::after or ::marker");
  92       return nullptr;
  93   }
  94 }
  95
  96 }  // namespace dom
  97 }  // namespace mozilla