2 * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Library General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Library General Public License for more details.
14 * You should have received a copy of the GNU Library General Public License
15 * along with this library; see the file COPYING.LIB. If not, write to
16 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
17 * Boston, MA 02110-1301, USA.
20 #ifndef MediaQueryMatcher_h
21 #define MediaQueryMatcher_h
23 #include "ScriptState.h"
24 #include <wtf/Forward.h>
25 #include <wtf/RefCounted.h>
26 #include <wtf/Vector.h>
33 class MediaQueryListListener;
34 class MediaQueryEvaluator;
36 // MediaQueryMatcher class is responsible for keeping a vector of pairs
37 // MediaQueryList x MediaQueryListListener. It is responsible for evaluating the queries
38 // whenever it is needed and to call the listeners if the corresponding query has changed.
39 // The listeners must be called in the very same order in which they have been added.
41 class MediaQueryMatcher : public RefCounted<MediaQueryMatcher> {
43 static PassRefPtr<MediaQueryMatcher> create(Document* document) { return adoptRef(new MediaQueryMatcher(document)); }
45 void documentDestroyed();
47 void addListener(PassRefPtr<MediaQueryListListener>, PassRefPtr<MediaQueryList>);
48 void removeListener(MediaQueryListListener*, MediaQueryList*);
50 PassRefPtr<MediaQueryList> matchMedia(const String&);
52 unsigned evaluationRound() const { return m_evaluationRound; }
53 void styleSelectorChanged();
54 bool evaluate(MediaList*);
59 Listener(PassRefPtr<MediaQueryListListener>, PassRefPtr<MediaQueryList>);
62 void evaluate(ScriptState*, MediaQueryEvaluator*);
64 MediaQueryListListener* listener() { return m_listener.get(); }
65 MediaQueryList* query() { return m_query.get(); }
68 RefPtr<MediaQueryListListener> m_listener;
69 RefPtr<MediaQueryList> m_query;
72 MediaQueryMatcher(Document*);
73 PassOwnPtr<MediaQueryEvaluator> prepareEvaluator() const;
74 String mediaType() const;
77 Vector<OwnPtr<Listener> > m_listeners;
79 // This value is incremented at style selector changes.
80 // It is used to avoid evaluating queries more then once and to make sure
81 // that a media query result change is notified exactly once.
82 unsigned m_evaluationRound;
87 #endif // MediaQueryMatcher_h