WebCore/accessibility/win/AXObjectCacheWin.cpp
changeset 0 4f2f89ce4247
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/WebCore/accessibility/win/AXObjectCacheWin.cpp	Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,143 @@
+/*
+ * Copyright (C) 2008, 2009, 2010 Apple Inc. All Rights Reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
+ */
+
+
+#include "config.h"
+#include "AXObjectCache.h"
+
+#include "AccessibilityObject.h"
+#include "Chrome.h"
+#include "Document.h"
+#include "Page.h"
+#include "RenderObject.h"
+
+using namespace std;
+
+namespace WebCore {
+
+void AXObjectCache::detachWrapper(AccessibilityObject* obj)
+{
+    // On Windows, AccessibilityObjects are created when get_accChildCount is
+    // called, but they are not wrapped until get_accChild is called, so this
+    // object may not have a wrapper.
+    if (AccessibilityObjectWrapper* wrapper = obj->wrapper())
+        wrapper->detach();
+}
+
+void AXObjectCache::attachWrapper(AccessibilityObject*)
+{
+    // On Windows, AccessibilityObjects are wrapped when the accessibility
+    // software requests them via get_accChild.
+}
+
+void AXObjectCache::handleScrolledToAnchor(const Node* anchorNode)
+{
+    // The anchor node may not be accessible. Post the notification for the
+    // first accessible object.
+    postPlatformNotification(AccessibilityObject::firstAccessibleObjectFromNode(anchorNode), AXScrolledToAnchor);
+}
+
+void AXObjectCache::postPlatformNotification(AccessibilityObject* obj, AXNotification notification)
+{
+    if (!obj)
+        return;
+
+    Document* document = obj->document();
+    if (!document)
+        return;
+
+    Page* page = document->page();
+    if (!page || !page->chrome()->platformPageClient())
+        return;
+
+    DWORD msaaEvent;
+    switch (notification) {
+        case AXFocusedUIElementChanged:
+        case AXActiveDescendantChanged:
+            msaaEvent = EVENT_OBJECT_FOCUS;
+            break;
+
+        case AXScrolledToAnchor:
+            msaaEvent = EVENT_SYSTEM_SCROLLINGSTART;
+            break;
+
+        case AXValueChanged:
+        case AXMenuListValueChanged:
+            msaaEvent = EVENT_OBJECT_VALUECHANGE;
+            break;
+
+        default:
+            return;
+    }
+
+    // Windows will end up calling get_accChild() on the root accessible
+    // object for the WebView, passing the child ID that we specify below. We
+    // negate the AXID so we know that the caller is passing the ID of an
+    // element, not the index of a child element.
+
+    ASSERT(obj->axObjectID() >= 1);
+    ASSERT(obj->axObjectID() <= numeric_limits<LONG>::max());
+
+    NotifyWinEvent(msaaEvent, page->chrome()->platformPageClient(), OBJID_CLIENT, -static_cast<LONG>(obj->axObjectID()));
+}
+
+AXID AXObjectCache::platformGenerateAXID() const
+{
+    static AXID lastUsedID = 0;
+
+    // Generate a new ID. Windows accessibility relies on a positive AXID,
+    // ranging from 1 to LONG_MAX.
+    AXID objID = lastUsedID;
+    do {
+        ++objID;
+        objID %= std::numeric_limits<LONG>::max();
+    } while (objID == 0 || HashTraits<AXID>::isDeletedValue(objID) || m_idsInUse.contains(objID));
+
+    ASSERT(objID >= 1 && objID <= std::numeric_limits<LONG>::max());
+
+    lastUsedID = objID;
+
+    return objID;
+}
+
+void AXObjectCache::handleFocusedUIElementChanged(RenderObject*, RenderObject* newFocusedRenderer)
+{
+    if (!newFocusedRenderer)
+        return;
+
+    Page* page = newFocusedRenderer->document()->page();
+    if (!page || !page->chrome()->platformPageClient())
+        return;
+
+    AccessibilityObject* focusedObject = focusedUIElementForPage(page);
+    if (!focusedObject)
+        return;
+
+    ASSERT(!focusedObject->accessibilityIsIgnored());
+
+    postPlatformNotification(focusedObject, AXFocusedUIElementChanged);
+}
+
+} // namespace WebCore