content/base/src/nsGenConImageContent.cpp

   1
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 /**
   7  * A fake content node class so that the image frame for
   8  *   content: url(foo);
   9  * in CSS can have an nsIImageLoadingContent but use an
  10  * imgIRequest that's already been loaded from the style system.
  11  */
  12
  13 #include "nsContentCreatorFunctions.h"
  14 #include "nsXMLElement.h"
  15 #include "nsImageLoadingContent.h"
  16 #include "imgIRequest.h"
  17 #include "mozilla/BasicEvents.h"
  18 #include "mozilla/EventDispatcher.h"
  19 #include "mozilla/EventStates.h"
  20
  21 using namespace mozilla;
  22
  23 class nsGenConImageContent MOZ_FINAL : public nsXMLElement,
  24                                        public nsImageLoadingContent
  25 {
  26 public:
  27   explicit nsGenConImageContent(already_AddRefed<mozilla::dom::NodeInfo>& aNodeInfo)
  28     : nsXMLElement(aNodeInfo)
  29   {
  30     // nsImageLoadingContent starts out broken, so we start out
  31     // suppressed to match it.
  32     AddStatesSilently(NS_EVENT_STATE_SUPPRESSED);
  33   }
  34
  35   nsresult Init(imgRequestProxy* aImageRequest)
  36   {
  37     // No need to notify, since we have no frame.
  38     return UseAsPrimaryRequest(aImageRequest, false);
  39   }
  40
  41   // nsIContent overrides
  42   virtual nsresult BindToTree(nsIDocument* aDocument, nsIContent* aParent,
  43                               nsIContent* aBindingParent,
  44                               bool aCompileEventHandlers);
  45   virtual void UnbindFromTree(bool aDeep, bool aNullParent);
  46   virtual EventStates IntrinsicState() const;
  47
  48   virtual nsresult PreHandleEvent(EventChainPreVisitor& aVisitor)
  49   {
  50     MOZ_ASSERT(IsInNativeAnonymousSubtree());
  51     if (aVisitor.mEvent->message == NS_LOAD ||
  52         aVisitor.mEvent->message == NS_LOAD_ERROR) {
  53       // Don't propagate the events to the parent.
  54       return NS_OK;
  55     }
  56     return nsXMLElement::PreHandleEvent(aVisitor);
  57   }
  58
  59 private:
  60   virtual ~nsGenConImageContent();
  61
  62 public:
  63   NS_DECL_ISUPPORTS_INHERITED
  64 };
  65
  66 NS_IMPL_ISUPPORTS_INHERITED(nsGenConImageContent,
  67                             nsXMLElement,
  68                             nsIImageLoadingContent,
  69                             imgINotificationObserver,
  70                             imgIOnloadBlocker)
  71
  72 nsresult
  73 NS_NewGenConImageContent(nsIContent** aResult, already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo,
  74                          imgRequestProxy* aImageRequest)
  75 {
  76   NS_PRECONDITION(aImageRequest, "Must have request!");
  77   nsGenConImageContent *it = new nsGenConImageContent(aNodeInfo);
  78   if (!it)
  79     return NS_ERROR_OUT_OF_MEMORY;
  80   NS_ADDREF(*aResult = it);
  81   nsresult rv = it->Init(aImageRequest);
  82   if (NS_FAILED(rv))
  83     NS_RELEASE(*aResult);
  84   return rv;
  85 }
  86
  87 nsGenConImageContent::~nsGenConImageContent()
  88 {
  89   DestroyImageLoadingContent();
  90 }
  91
  92 nsresult
  93 nsGenConImageContent::BindToTree(nsIDocument* aDocument, nsIContent* aParent,
  94                                  nsIContent* aBindingParent,
  95                                  bool aCompileEventHandlers)
  96 {
  97   nsresult rv;
  98   rv = nsXMLElement::BindToTree(aDocument, aParent, aBindingParent,
  99                                 aCompileEventHandlers);
 100   NS_ENSURE_SUCCESS(rv, rv);
 101
 102   nsImageLoadingContent::BindToTree(aDocument, aParent, aBindingParent,
 103                                     aCompileEventHandlers);
 104   return NS_OK;
 105 }
 106
 107 void
 108 nsGenConImageContent::UnbindFromTree(bool aDeep, bool aNullParent)
 109 {
 110   nsImageLoadingContent::UnbindFromTree(aDeep, aNullParent);
 111   nsXMLElement::UnbindFromTree(aDeep, aNullParent);
 112 }
 113
 114 EventStates
 115 nsGenConImageContent::IntrinsicState() const
 116 {
 117   EventStates state = nsXMLElement::IntrinsicState();
 118
 119   EventStates imageState = nsImageLoadingContent::ImageState();
 120   if (imageState.HasAtLeastOneOfStates(NS_EVENT_STATE_BROKEN | NS_EVENT_STATE_USERDISABLED)) {
 121     // We should never be in an error state; if the image fails to load, we
 122     // just go to the suppressed state.
 123     imageState |= NS_EVENT_STATE_SUPPRESSED;
 124     imageState &= ~NS_EVENT_STATE_BROKEN;
 125   }
 126   imageState &= ~NS_EVENT_STATE_LOADING;
 127   return state | imageState;
 128 }