blob: 033afb0d725e47652ce862718972764a939c5cc7 [file] [log] [blame]
/*
* Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public License
* along with this library; see the file COPYING.LIB. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#pragma once
#include <memory>
#include <wtf/Forward.h>
#include <wtf/RefCounted.h>
#include <wtf/Vector.h>
#include <wtf/WeakPtr.h>
namespace WebCore {
class Document;
class MediaQueryList;
class MediaQueryListListener;
class MediaQueryEvaluator;
class MediaQuerySet;
class RenderStyle;
// MediaQueryMatcher class is responsible for keeping a vector of pairs
// MediaQueryList x MediaQueryListListener. It is responsible for evaluating the queries
// whenever it is needed and to call the listeners if the corresponding query has changed.
// The listeners must be called in the order in which they were added.
class MediaQueryMatcher final : public RefCounted<MediaQueryMatcher> {
public:
static Ref<MediaQueryMatcher> create(Document& document) { return adoptRef(*new MediaQueryMatcher(document)); }
~MediaQueryMatcher();
void documentDestroyed();
void addListener(Ref<MediaQueryListListener>&&, MediaQueryList&);
void removeListener(MediaQueryListListener&, MediaQueryList&);
RefPtr<MediaQueryList> matchMedia(const String&);
unsigned evaluationRound() const { return m_evaluationRound; }
void styleResolverChanged();
bool evaluate(const MediaQuerySet&);
private:
struct Listener {
Ref<MediaQueryListListener> listener;
Ref<MediaQueryList> query;
};
explicit MediaQueryMatcher(Document&);
std::unique_ptr<RenderStyle> documentElementUserAgentStyle() const;
String mediaType() const;
WeakPtr<Document> m_document;
Vector<Listener> m_listeners;
// This value is incremented at style selector changes.
// It is used to avoid evaluating queries more then once and to make sure
// that a media query result change is notified exactly once.
unsigned m_evaluationRound { 1 };
};
} // namespace WebCore