1 /*
2 * Copyright (C) 2003, 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
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 COMPUTER, INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26 #ifndef AXObjectCache_h
27 #define AXObjectCache_h
28
29 #include "AccessibilityObject.h"
30 #include "EventHandler.h"
31 #include "Timer.h"
32 #include <limits.h>
33 #include <wtf/HashMap.h>
34 #include <wtf/HashSet.h>
35 #include <wtf/RefPtr.h>
36
37 #ifdef __OBJC__
38 @class WebCoreTextMarker;
39 #else
40 class WebCoreTextMarker;
41 #endif
42
43 namespace WebCore {
44
45 class HTMLAreaElement;
46 class Node;
47 class Page;
48 class RenderObject;
49 class String;
50 class VisiblePosition;
51
52 struct TextMarkerData {
53 AXID axID;
54 Node* node;
55 int offset;
56 EAffinity affinity;
57 };
58
59 enum PostType { PostSynchronously, PostAsynchronously };
60
61 class AXObjectCache : public Noncopyable {
62 public:
63 AXObjectCache();
64 ~AXObjectCache();
65
66 static AccessibilityObject* focusedUIElementForPage(const Page*);
67
68 // to be used with render objects
69 AccessibilityObject* getOrCreate(RenderObject*);
70
71 // used for objects without backing elements
72 AccessibilityObject* getOrCreate(AccessibilityRole);
73
74 // will only return the AccessibilityObject if it already exists
75 AccessibilityObject* get(RenderObject*);
76
77 void remove(RenderObject*);
78 void remove(AXID);
79
80 void detachWrapper(AccessibilityObject*);
81 void attachWrapper(AccessibilityObject*);
82 void childrenChanged(RenderObject*);
83 void selectedChildrenChanged(RenderObject*);
84 // Called by a node when text or a text equivalent (e.g. alt) attribute is changed.
85 void contentChanged(RenderObject*);
86
87 void handleActiveDescendantChanged(RenderObject*);
88 void handleAriaRoleChanged(RenderObject*);
89 void handleFocusedUIElementChanged(RenderObject* oldFocusedRenderer, RenderObject* newFocusedRenderer);
90 void handleScrolledToAnchor(const Node* anchorNode);
91
enableAccessibility()92 static void enableAccessibility() { gAccessibilityEnabled = true; }
enableEnhancedUserInterfaceAccessibility()93 static void enableEnhancedUserInterfaceAccessibility() { gAccessibilityEnhancedUserInterfaceEnabled = true; }
94
accessibilityEnabled()95 static bool accessibilityEnabled() { return gAccessibilityEnabled; }
accessibilityEnhancedUserInterfaceEnabled()96 static bool accessibilityEnhancedUserInterfaceEnabled() { return gAccessibilityEnhancedUserInterfaceEnabled; }
97
98 void removeAXID(AccessibilityObject*);
isIDinUse(AXID id)99 bool isIDinUse(AXID id) const { return m_idsInUse.contains(id); }
100 AXID platformGenerateAXID() const;
objectFromAXID(AXID id)101 AccessibilityObject* objectFromAXID(AXID id) const { return m_objects.get(id).get(); }
102
103 // Text marker utilities.
104 static void textMarkerDataForVisiblePosition(TextMarkerData&, const VisiblePosition&);
105 static VisiblePosition visiblePositionForTextMarkerData(TextMarkerData&);
106
107 enum AXNotification {
108 AXActiveDescendantChanged,
109 AXCheckedStateChanged,
110 AXFocusedUIElementChanged,
111 AXLayoutComplete,
112 AXLoadComplete,
113 AXSelectedChildrenChanged,
114 AXSelectedTextChanged,
115 AXValueChanged,
116 AXScrolledToAnchor,
117 AXLiveRegionChanged,
118 AXMenuListValueChanged,
119 };
120
121 void postNotification(RenderObject*, AXNotification, bool postToElement, PostType = PostAsynchronously);
122 void postNotification(AccessibilityObject*, Document*, AXNotification, bool postToElement, PostType = PostAsynchronously);
123
124 protected:
125 void postPlatformNotification(AccessibilityObject*, AXNotification);
126
127 private:
128 HashMap<AXID, RefPtr<AccessibilityObject> > m_objects;
129 HashMap<RenderObject*, AXID> m_renderObjectMapping;
130 static bool gAccessibilityEnabled;
131 static bool gAccessibilityEnhancedUserInterfaceEnabled;
132
133 HashSet<AXID> m_idsInUse;
134
135 Timer<AXObjectCache> m_notificationPostTimer;
136 Vector<pair<RefPtr<AccessibilityObject>, AXNotification> > m_notificationsToPost;
137 void notificationPostTimerFired(Timer<AXObjectCache>*);
138
139 static AccessibilityObject* focusedImageMapUIElement(HTMLAreaElement*);
140
141 AXID getAXID(AccessibilityObject*);
142 bool nodeIsAriaType(Node*, String role);
143 };
144
145 #if !HAVE(ACCESSIBILITY)
handleActiveDescendantChanged(RenderObject *)146 inline void AXObjectCache::handleActiveDescendantChanged(RenderObject*) { }
handleAriaRoleChanged(RenderObject *)147 inline void AXObjectCache::handleAriaRoleChanged(RenderObject*) { }
detachWrapper(AccessibilityObject *)148 inline void AXObjectCache::detachWrapper(AccessibilityObject*) { }
attachWrapper(AccessibilityObject *)149 inline void AXObjectCache::attachWrapper(AccessibilityObject*) { }
selectedChildrenChanged(RenderObject *)150 inline void AXObjectCache::selectedChildrenChanged(RenderObject*) { }
postNotification(RenderObject *,AXNotification,bool postToElement,PostType)151 inline void AXObjectCache::postNotification(RenderObject*, AXNotification, bool postToElement, PostType) { }
postPlatformNotification(AccessibilityObject *,AXNotification)152 inline void AXObjectCache::postPlatformNotification(AccessibilityObject*, AXNotification) { }
handleFocusedUIElementChanged(RenderObject *,RenderObject *)153 inline void AXObjectCache::handleFocusedUIElementChanged(RenderObject*, RenderObject*) { }
handleScrolledToAnchor(const Node *)154 inline void AXObjectCache::handleScrolledToAnchor(const Node*) { }
contentChanged(RenderObject *)155 inline void AXObjectCache::contentChanged(RenderObject*) { }
156 #endif
157
158 }
159
160 #endif
161