gecko/layout/style/nsDOMMediaQueryList.cpp

165 lines
5.0 KiB
C++

/* vim: set shiftwidth=2 tabstop=8 autoindent cindent expandtab: */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is nsDOMMediaQueryList.
*
* The Initial Developer of the Original Code is the Mozilla Foundation.
* Portions created by the Initial Developer are Copyright (C) 2011
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* L. David Baron <dbaron@dbaron.org>, Mozilla Corporation (original author)
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
/* implements DOM interface for querying and observing media queries */
#include "nsDOMMediaQueryList.h"
#include "nsPresContext.h"
#include "nsIMediaList.h"
#include "nsCSSParser.h"
nsDOMMediaQueryList::nsDOMMediaQueryList(nsPresContext *aPresContext,
const nsAString &aMediaQueryList)
: mPresContext(aPresContext),
mMediaList(new nsMediaList),
mMatchesValid(PR_FALSE)
{
PR_INIT_CLIST(this);
nsCSSParser parser;
parser.ParseMediaList(aMediaQueryList, nsnull, 0, mMediaList, PR_FALSE);
}
nsDOMMediaQueryList::~nsDOMMediaQueryList()
{
if (mPresContext) {
PR_REMOVE_LINK(this);
}
}
NS_IMPL_CYCLE_COLLECTION_CLASS(nsDOMMediaQueryList)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(nsDOMMediaQueryList)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_NSCOMPTR(mPresContext)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_NSTARRAY_OF_NSCOMPTR(mListeners)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(nsDOMMediaQueryList)
if (tmp->mPresContext) {
PR_REMOVE_LINK(tmp);
NS_IMPL_CYCLE_COLLECTION_UNLINK_NSCOMPTR(mPresContext)
}
NS_IMPL_CYCLE_COLLECTION_UNLINK_NSCOMARRAY(mListeners)
NS_IMPL_CYCLE_COLLECTION_UNLINK_END
DOMCI_DATA(MediaQueryList, nsDOMMediaQueryList)
NS_INTERFACE_MAP_BEGIN(nsDOMMediaQueryList)
NS_INTERFACE_MAP_ENTRY(nsIDOMMediaQueryList)
NS_INTERFACE_MAP_ENTRY(nsISupports)
NS_INTERFACE_MAP_ENTRIES_CYCLE_COLLECTION(nsDOMMediaQueryList)
NS_DOM_INTERFACE_MAP_ENTRY_CLASSINFO(MediaQueryList)
NS_INTERFACE_MAP_END
NS_IMPL_CYCLE_COLLECTING_ADDREF(nsDOMMediaQueryList)
NS_IMPL_CYCLE_COLLECTING_RELEASE(nsDOMMediaQueryList)
NS_IMETHODIMP
nsDOMMediaQueryList::GetMedia(nsAString &aMedia)
{
mMediaList->GetText(aMedia);
return NS_OK;
}
NS_IMETHODIMP
nsDOMMediaQueryList::GetMatches(PRBool *aMatches)
{
if (!mMatchesValid) {
NS_ABORT_IF_FALSE(mListeners.Length() == 0,
"when listeners present, must keep mMatches current");
RecomputeMatches();
}
*aMatches = mMatches;
return NS_OK;
}
NS_IMETHODIMP
nsDOMMediaQueryList::AddListener(nsIDOMMediaQueryListListener *aListener)
{
if (!mMatchesValid) {
NS_ABORT_IF_FALSE(mListeners.Length() == 0,
"when listeners present, must keep mMatches current");
RecomputeMatches();
}
if (!mListeners.Contains(aListener)) {
mListeners.AppendElement(aListener);
}
return NS_OK;
}
NS_IMETHODIMP
nsDOMMediaQueryList::RemoveListener(nsIDOMMediaQueryListListener *aListener)
{
mListeners.RemoveElement(aListener);
NS_ABORT_IF_FALSE(!mListeners.Contains(aListener),
"duplicate occurrence of listeners");
return NS_OK;
}
void
nsDOMMediaQueryList::RecomputeMatches()
{
if (!mPresContext) {
return;
}
mMatches = mMediaList->Matches(mPresContext, nsnull);
mMatchesValid = PR_TRUE;
}
void
nsDOMMediaQueryList::MediumFeaturesChanged(NotifyList &aListenersToNotify)
{
mMatchesValid = PR_FALSE;
if (mListeners.Length()) {
PRPackedBool oldMatches = mMatches;
RecomputeMatches();
if (mMatches != oldMatches) {
for (PRUint32 i = 0, i_end = mListeners.Length(); i != i_end; ++i) {
HandleChangeData *d = aListenersToNotify.AppendElement();
if (d) {
d->mql = this;
d->listener = mListeners[i];
}
}
}
}
}