1 /* 2 * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies) 3 * 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. 8 * 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. 13 * 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. 18 */ 19 20 #include "config.h" 21 #include "core/css/MediaQueryMatcher.h" 22 23 #include "core/css/MediaList.h" 24 #include "core/css/MediaQueryEvaluator.h" 25 #include "core/css/MediaQueryList.h" 26 #include "core/css/MediaQueryListListener.h" 27 #include "core/css/resolver/StyleResolver.h" 28 #include "core/dom/Document.h" 29 #include "core/page/Frame.h" 30 #include "core/page/FrameView.h" 31 32 namespace WebCore { 33 34 MediaQueryMatcher::Listener::Listener(PassRefPtr<MediaQueryListListener> listener, PassRefPtr<MediaQueryList> query) 35 : m_listener(listener) 36 , m_query(query) 37 { 38 } 39 40 MediaQueryMatcher::Listener::~Listener() 41 { 42 } 43 44 void MediaQueryMatcher::Listener::evaluate(ScriptState* state, MediaQueryEvaluator* evaluator) 45 { 46 bool notify; 47 m_query->evaluate(evaluator, notify); 48 if (notify) 49 m_listener->queryChanged(state, m_query.get()); 50 } 51 52 MediaQueryMatcher::MediaQueryMatcher(Document* document) 53 : m_document(document) 54 , m_evaluationRound(1) 55 { 56 ASSERT(m_document); 57 } 58 59 MediaQueryMatcher::~MediaQueryMatcher() 60 { 61 } 62 63 void MediaQueryMatcher::documentDestroyed() 64 { 65 m_listeners.clear(); 66 m_document = 0; 67 } 68 69 AtomicString MediaQueryMatcher::mediaType() const 70 { 71 if (!m_document || !m_document->frame() || !m_document->frame()->view()) 72 return nullAtom; 73 74 return m_document->frame()->view()->mediaType(); 75 } 76 77 PassOwnPtr<MediaQueryEvaluator> MediaQueryMatcher::prepareEvaluator() const 78 { 79 if (!m_document || !m_document->frame()) 80 return nullptr; 81 82 Element* documentElement = m_document->documentElement(); 83 if (!documentElement) 84 return nullptr; 85 86 StyleResolver* styleResolver = m_document->styleResolver(); 87 if (!styleResolver) 88 return nullptr; 89 90 RefPtr<RenderStyle> rootStyle = styleResolver->styleForElement(documentElement, 0 /*defaultParent*/, DisallowStyleSharing, MatchOnlyUserAgentRules); 91 92 return adoptPtr(new MediaQueryEvaluator(mediaType(), m_document->frame(), rootStyle.get())); 93 } 94 95 bool MediaQueryMatcher::evaluate(const MediaQuerySet* media) 96 { 97 if (!media) 98 return false; 99 100 OwnPtr<MediaQueryEvaluator> evaluator(prepareEvaluator()); 101 return evaluator && evaluator->eval(media); 102 } 103 104 PassRefPtr<MediaQueryList> MediaQueryMatcher::matchMedia(const String& query) 105 { 106 if (!m_document) 107 return 0; 108 109 RefPtr<MediaQuerySet> media = MediaQuerySet::create(query); 110 // Add warning message to inspector whenever dpi/dpcm values are used for "screen" media. 111 reportMediaQueryWarningIfNeeded(m_document, media.get()); 112 return MediaQueryList::create(this, media, evaluate(media.get())); 113 } 114 115 void MediaQueryMatcher::addListener(PassRefPtr<MediaQueryListListener> listener, PassRefPtr<MediaQueryList> query) 116 { 117 if (!m_document) 118 return; 119 120 for (size_t i = 0; i < m_listeners.size(); ++i) { 121 if (*m_listeners[i]->listener() == *listener && m_listeners[i]->query() == query) 122 return; 123 } 124 125 m_listeners.append(adoptPtr(new Listener(listener, query))); 126 } 127 128 void MediaQueryMatcher::removeListener(MediaQueryListListener* listener, MediaQueryList* query) 129 { 130 if (!m_document) 131 return; 132 133 for (size_t i = 0; i < m_listeners.size(); ++i) { 134 if (*m_listeners[i]->listener() == *listener && m_listeners[i]->query() == query) { 135 m_listeners.remove(i); 136 return; 137 } 138 } 139 } 140 141 void MediaQueryMatcher::styleResolverChanged() 142 { 143 ASSERT(m_document); 144 145 ScriptState* scriptState = mainWorldScriptState(m_document->frame()); 146 if (!scriptState) 147 return; 148 149 ++m_evaluationRound; 150 OwnPtr<MediaQueryEvaluator> evaluator = prepareEvaluator(); 151 if (!evaluator) 152 return; 153 154 for (size_t i = 0; i < m_listeners.size(); ++i) 155 m_listeners[i]->evaluate(scriptState, evaluator.get()); 156 } 157 158 } 159