1 | /* |
2 | * Copyright (C) 2019 Igalia S.L. |
3 | * |
4 | * Redistribution and use in source and binary forms, with or without |
5 | * modification, are permitted provided that the following conditions |
6 | * are met: |
7 | * 1. Redistributions of source code must retain the above copyright |
8 | * notice, this list of conditions and the following disclaimer. |
9 | * 2. Redistributions in binary form must reproduce the above copyright |
10 | * notice, this list of conditions and the following disclaimer in the |
11 | * documentation and/or other materials provided with the distribution. |
12 | * |
13 | * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' |
14 | * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, |
15 | * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
16 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS |
17 | * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
18 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
19 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
20 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
21 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
22 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF |
23 | * THE POSSIBILITY OF SUCH DAMAGE. |
24 | */ |
25 | |
26 | #include "config.h" |
27 | |
28 | #if ENABLE(RESIZE_OBSERVER) |
29 | #include "ResizeObserver.h" |
30 | |
31 | #include "Element.h" |
32 | #include "ResizeObserverEntry.h" |
33 | |
34 | namespace WebCore { |
35 | |
36 | Ref<ResizeObserver> ResizeObserver::create(Document& document, Ref<ResizeObserverCallback>&& callback) |
37 | { |
38 | return adoptRef(*new ResizeObserver(document, WTFMove(callback))); |
39 | } |
40 | |
41 | ResizeObserver::ResizeObserver(Document& document, Ref<ResizeObserverCallback>&& callback) |
42 | : ActiveDOMObject(callback->scriptExecutionContext()) |
43 | , m_document(makeWeakPtr(document)) |
44 | , m_callback(WTFMove(callback)) |
45 | { |
46 | suspendIfNeeded(); |
47 | } |
48 | |
49 | ResizeObserver::~ResizeObserver() |
50 | { |
51 | disconnect(); |
52 | if (m_document) |
53 | m_document->removeResizeObserver(*this); |
54 | } |
55 | |
56 | void ResizeObserver::observe(Element& target) |
57 | { |
58 | if (!m_callback) |
59 | return; |
60 | |
61 | auto position = m_observations.findMatching([&](auto& observation) { |
62 | return observation->target() == ⌖ |
63 | }); |
64 | |
65 | if (position != notFound) |
66 | return; |
67 | |
68 | auto& observerData = target.ensureResizeObserverData(); |
69 | observerData.observers.append(makeWeakPtr(this)); |
70 | |
71 | m_observations.append(ResizeObservation::create(&target)); |
72 | m_pendingTargets.append(target); |
73 | |
74 | if (m_document) { |
75 | m_document->addResizeObserver(*this); |
76 | m_document->scheduleTimedRenderingUpdate(); |
77 | } |
78 | } |
79 | |
80 | void ResizeObserver::unobserve(Element& target) |
81 | { |
82 | if (!removeTarget(target)) |
83 | return; |
84 | |
85 | removeObservation(target); |
86 | } |
87 | |
88 | void ResizeObserver::disconnect() |
89 | { |
90 | removeAllTargets(); |
91 | } |
92 | |
93 | void ResizeObserver::targetDestroyed(Element& target) |
94 | { |
95 | removeObservation(target); |
96 | } |
97 | |
98 | size_t ResizeObserver::gatherObservations(size_t deeperThan) |
99 | { |
100 | m_hasSkippedObservations = false; |
101 | size_t minObservedDepth = maxElementDepth(); |
102 | for (const auto& observation : m_observations) { |
103 | LayoutSize currentSize; |
104 | if (observation->elementSizeChanged(currentSize)) { |
105 | size_t depth = observation->targetElementDepth(); |
106 | if (depth > deeperThan) { |
107 | observation->updateObservationSize(currentSize); |
108 | m_activeObservations.append(observation.get()); |
109 | minObservedDepth = std::min(depth, minObservedDepth); |
110 | } else |
111 | m_hasSkippedObservations = true; |
112 | } |
113 | } |
114 | return minObservedDepth; |
115 | } |
116 | |
117 | void ResizeObserver::deliverObservations() |
118 | { |
119 | Vector<Ref<ResizeObserverEntry>> entries; |
120 | for (const auto& observation : m_activeObservations) { |
121 | ASSERT(observation->target()); |
122 | entries.append(ResizeObserverEntry::create(observation->target(), observation->computeContentRect())); |
123 | } |
124 | m_activeObservations.clear(); |
125 | m_callback->handleEvent(entries, *this); |
126 | } |
127 | |
128 | bool ResizeObserver::removeTarget(Element& target) |
129 | { |
130 | auto* observerData = target.resizeObserverData(); |
131 | if (!observerData) |
132 | return false; |
133 | |
134 | auto& observers = observerData->observers; |
135 | return observers.removeFirst(this); |
136 | } |
137 | |
138 | void ResizeObserver::removeAllTargets() |
139 | { |
140 | for (auto& observation : m_observations) { |
141 | bool removed = removeTarget(*observation->target()); |
142 | ASSERT_UNUSED(removed, removed); |
143 | } |
144 | m_pendingTargets.clear(); |
145 | m_activeObservations.clear(); |
146 | m_observations.clear(); |
147 | } |
148 | |
149 | bool ResizeObserver::removeObservation(const Element& target) |
150 | { |
151 | m_pendingTargets.removeFirstMatching([&target](auto& pendingTarget) { |
152 | return pendingTarget.ptr() == ⌖ |
153 | }); |
154 | |
155 | m_activeObservations.removeFirstMatching([&target](auto& observation) { |
156 | return observation->target() == ⌖ |
157 | }); |
158 | |
159 | return m_observations.removeFirstMatching([&target](auto& observation) { |
160 | return observation->target() == ⌖ |
161 | }); |
162 | } |
163 | |
164 | bool ResizeObserver::hasPendingActivity() const |
165 | { |
166 | return (hasObservations() && m_document) || !m_activeObservations.isEmpty(); |
167 | } |
168 | |
169 | const char* ResizeObserver::activeDOMObjectName() const |
170 | { |
171 | return "ResizeObserver" ; |
172 | } |
173 | |
174 | bool ResizeObserver::canSuspendForDocumentSuspension() const |
175 | { |
176 | return true; |
177 | } |
178 | |
179 | void ResizeObserver::stop() |
180 | { |
181 | disconnect(); |
182 | m_callback = nullptr; |
183 | } |
184 | |
185 | } // namespace WebCore |
186 | |
187 | #endif // ENABLE(RESIZE_OBSERVER) |
188 | |