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/*
* Copyright (C) 2008 Apple Ltd.
* Copyright (C) 2008 Alp Toker <alp@atoker.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public License
* along with this library; see the file COPYING.LIB. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#include "config.h"
#include "AccessibilityObject.h"
#include "RenderObject.h"
#include "RenderText.h"
#include <glib-object.h>
#if HAVE(ACCESSIBILITY)
namespace WebCore {
bool AccessibilityObject::accessibilityIgnoreAttachment() const
{
return false;
}
AccessibilityObjectInclusion AccessibilityObject::accessibilityPlatformIncludesObject() const
{
AccessibilityObject* parent = parentObject();
if (!parent)
return DefaultBehavior;
AccessibilityRole role = roleValue();
if (role == HorizontalRuleRole)
return IncludeObject;
// We expose the slider as a whole but not its value indicator.
if (role == SliderThumbRole)
return IgnoreObject;
// When a list item is made up entirely of children (e.g. paragraphs)
// the list item gets ignored. We need it.
if (isGroup() && parent->isList())
return IncludeObject;
// Entries and password fields have extraneous children which we want to ignore.
if (parent->isPasswordField() || parent->isTextControl())
return IgnoreObject;
// Include all tables, even layout tables. The AT can decide what to do with each.
if (role == CellRole || role == TableRole)
return IncludeObject;
// The object containing the text should implement AtkText itself.
if (role == StaticTextRole)
return IgnoreObject;
// Include all list items, regardless they have or not inline children
if (role == ListItemRole)
return IncludeObject;
// Bullets/numbers for list items shouldn't be exposed as AtkObjects.
if (role == ListMarkerRole)
return IgnoreObject;
// Never expose an unknown object, since AT's won't know what to
// do with them. This is what is done on the Mac as well.
if (role == UnknownRole)
return IgnoreObject;
// Given a paragraph or div containing a non-nested anonymous block, WebCore
// ignores the paragraph or div and includes the block. We want the opposite:
// ATs are expecting accessible objects associated with textual elements. They
// usually have no need for the anonymous block. And when the wrong objects
// get included or ignored, needed accessibility signals do not get emitted.
if (role == ParagraphRole || role == DivRole) {
// Don't call textUnderElement() here, because it's slow and it can
// crash when called while we're in the middle of a subtree being deleted.
if (!renderer()->firstChild())
return DefaultBehavior;
if (!parent->renderer() || parent->renderer()->isAnonymousBlock())
return DefaultBehavior;
for (RenderObject* r = renderer()->firstChild(); r; r = r->nextSibling()) {
if (r->isAnonymousBlock())
return IncludeObject;
}
}
// Block spans result in objects of ATK_ROLE_PANEL which are almost always unwanted.
// However, if we ignore block spans whose parent is the body, the child controls
// will become immediate children of the ATK_ROLE_DOCUMENT_FRAME and any text will
// become text within the document frame itself. This ultimately may be what we want
// and would largely be consistent with what we see from Gecko. However, ignoring
// spans whose parent is the body changes the current behavior we see from WebCore.
// Until we have sufficient time to properly analyze these cases, we will defer to
// WebCore. We only check that the parent is not aria because we do not expect
// anonymous blocks which are aria-related to themselves have an aria role, nor
// have we encountered instances where the parent of an anonymous block also lacked
// an aria role but the grandparent had one.
if (renderer() && renderer()->isAnonymousBlock() && !parent->renderer()->isBody()
&& parent->ariaRoleAttribute() == UnknownRole)
return IgnoreObject;
return DefaultBehavior;
}
AccessibilityObjectWrapper* AccessibilityObject::wrapper() const
{
return m_wrapper;
}
void AccessibilityObject::setWrapper(AccessibilityObjectWrapper* wrapper)
{
if (wrapper == m_wrapper)
return;
if (m_wrapper)
g_object_unref(m_wrapper);
m_wrapper = wrapper;
if (m_wrapper)
g_object_ref(m_wrapper);
}
bool AccessibilityObject::allowsTextRanges() const
{
// Check type for the AccessibilityObject.
if (isTextControl() || isWebArea() || isGroup() || isLink() || isHeading() || isListItem() || isTableCell())
return true;
// Check roles as the last fallback mechanism.
AccessibilityRole role = roleValue();
return role == ParagraphRole || role == LabelRole || role == DivRole || role == FormRole;
}
unsigned AccessibilityObject::getLengthForTextRange() const
{
unsigned textLength = text().length();
if (textLength)
return textLength;
// Gtk ATs need this for all text objects; not just text controls.
Node* node = this->node();
RenderObject* renderer = node ? node->renderer() : 0;
if (renderer && renderer->isText()) {
RenderText* renderText = toRenderText(renderer);
textLength = renderText ? renderText->textLength() : 0;
}
// Get the text length from the elements under the
// accessibility object if the value is still zero.
if (!textLength && allowsTextRanges())
textLength = textUnderElement(TextUnderElementModeIncludeAllChildren).length();
return textLength;
}
} // namespace WebCore
#endif // HAVE(ACCESSIBILITY)
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