The Tor Browser: layout/style/MediaQueryList.cpp@8bccb770b82d (annotated)

layout/style/MediaQueryList.cpp@8bccb770b82d (annotated)

layout/style/MediaQueryList.cpp

Wed, 31 Dec 2014 13:27:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 13:27:57 +0100
branch: TOR_BUG_3246
changeset 6: 8bccb770b82d
permissions: -rw-r--r--

Ignore runtime configuration files generated during quality assurance.

 /* 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/. */
 /* implements DOM interface for querying and observing media queries */
 #include "mozilla/dom/MediaQueryList.h"
 #include "nsPresContext.h"
 #include "nsIMediaList.h"
 #include "nsCSSParser.h"
 #include "nsIDocument.h"
 namespace mozilla {
 namespace dom {
 MediaQueryList::MediaQueryList(nsPresContext *aPresContext,
                                const nsAString &aMediaQueryList)
   : mPresContext(aPresContext),
     mMediaList(new nsMediaList),
     mMatchesValid(false)
 {
   PR_INIT_CLIST(this);
   SetIsDOMBinding();
   nsCSSParser parser;
   parser.ParseMediaList(aMediaQueryList, nullptr, 0, mMediaList, false);
 }
 MediaQueryList::~MediaQueryList()
 {
   if (mPresContext) {
     PR_REMOVE_LINK(this);
   }
 }
 NS_IMPL_CYCLE_COLLECTION_CLASS(MediaQueryList)
 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(MediaQueryList)
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mPresContext)
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mCallbacks)
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE_SCRIPT_OBJECTS
 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
 NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(MediaQueryList)
   if (tmp->mPresContext) {
     PR_REMOVE_LINK(tmp);
     NS_IMPL_CYCLE_COLLECTION_UNLINK(mPresContext)
   }
   tmp->RemoveAllListeners();
   NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER
 NS_IMPL_CYCLE_COLLECTION_UNLINK_END
 NS_IMPL_CYCLE_COLLECTION_TRACE_WRAPPERCACHE(MediaQueryList)
 NS_INTERFACE_MAP_BEGIN(MediaQueryList)
   NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
   NS_INTERFACE_MAP_ENTRY(nsISupports)
   NS_INTERFACE_MAP_ENTRIES_CYCLE_COLLECTION(MediaQueryList)
 NS_INTERFACE_MAP_END
 NS_IMPL_CYCLE_COLLECTING_ADDREF(MediaQueryList)
 NS_IMPL_CYCLE_COLLECTING_RELEASE(MediaQueryList)
 void
 MediaQueryList::GetMedia(nsAString &aMedia)
 {
   mMediaList->GetText(aMedia);
 }
 bool
 MediaQueryList::Matches()
 {
   if (!mMatchesValid) {
     NS_ABORT_IF_FALSE(!HasListeners(),
                       "when listeners present, must keep mMatches current");
     RecomputeMatches();
   }
   return mMatches;
 }
 void
 MediaQueryList::AddListener(MediaQueryListListener& aListener)
 {
   if (!HasListeners()) {
     // When we have listeners, the pres context owns a reference to
     // this.  This is a cyclic reference that can only be broken by
     // cycle collection.
     NS_ADDREF_THIS();
   }
   if (!mMatchesValid) {
     NS_ABORT_IF_FALSE(!HasListeners(),
                       "when listeners present, must keep mMatches current");
     RecomputeMatches();
   }
   for (uint32_t i = 0; i < mCallbacks.Length(); ++i) {
     if (aListener == *mCallbacks[i]) {
       // Already registered
       return;
     }
   }
   mCallbacks.AppendElement(&aListener);
   if (!HasListeners()) {
     // Append failed; undo the AddRef above.
     NS_RELEASE_THIS();
   }
 }
 void
 MediaQueryList::RemoveListener(MediaQueryListListener& aListener)
 {
   for (uint32_t i = 0; i < mCallbacks.Length(); ++i) {
     if (aListener == *mCallbacks[i]) {
       mCallbacks.RemoveElementAt(i);
       if (!HasListeners()) {
         // See NS_ADDREF_THIS() in AddListener.
         NS_RELEASE_THIS();
       }
       break;
     }
   }
 }
 void
 MediaQueryList::RemoveAllListeners()
 {
   bool hadListeners = HasListeners();
   mCallbacks.Clear();
   if (hadListeners) {
     // See NS_ADDREF_THIS() in AddListener.
     NS_RELEASE_THIS();
   }
 }
 void
 MediaQueryList::RecomputeMatches()
 {
   if (!mPresContext) {
     return;
   }
   mMatches = mMediaList->Matches(mPresContext, nullptr);
   mMatchesValid = true;
 }
 void
 MediaQueryList::MediumFeaturesChanged(NotifyList &aListenersToNotify)
 {
   mMatchesValid = false;
   if (HasListeners()) {
     bool oldMatches = mMatches;
     RecomputeMatches();
     if (mMatches != oldMatches) {
       for (uint32_t i = 0, i_end = mCallbacks.Length(); i != i_end; ++i) {
         HandleChangeData *d = aListenersToNotify.AppendElement();
         if (d) {
           d->mql = this;
           d->callback = mCallbacks[i];
         }
       }
     }
   }
 }
 nsISupports*
 MediaQueryList::GetParentObject() const
 {
   if (!mPresContext) {
     return nullptr;
   }
   return mPresContext->Document();
 }
 JSObject*
 MediaQueryList::WrapObject(JSContext* aCx)
 {
   return MediaQueryListBinding::Wrap(aCx, this);
 }
 } // namespace dom
 } // namespace mozilla

The Tor Browser / annotate

layout/style/MediaQueryList.cpp@8bccb770b82d (annotated)

layout/style/MediaQueryList.cpp