Accessibility Mac: Cache Accessible Elements and Notify about changes

The big change is that we now keep the id objects representing accessibles
around so that they are persistent for ATs.
This improves performance of Mac accessibility significantly.

This is required for notifications which are now sent so that many things work much better,
for example the VoiceOver focus follows the keyboard focus.

The parent element in QCocoaAccessibleElement was removed, we can
dynamically access it more reliably.

Change-Id: I686d212f40d28b392dcc22f16f3c3430f08bdc98
Reviewed-by: Morten Johan Sørvig <morten.sorvig@digia.com>

1 files changed, 67 insertions, 0 deletions

diff --git a/src/gui/accessible/qaccessiblecache_mac.mm b/src/gui/accessible/qaccessiblecache_mac.mm
new file mode 100644
index 0000000000..861423af7d
--- /dev/null
+++ b/src/gui/accessible/qaccessiblecache_mac.mm
@@ -0,0 +1,67 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the QtGui module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qaccessiblecache_p.h"
+
+#ifdef Q_OS_OSX
+
+QT_BEGIN_NAMESPACE
+
+void QAccessibleCache::insertElement(QAccessible::Id axid, QCocoaAccessibleElement *element) const
+{
+    cocoaElements[axid] = element;
+}
+
+void QAccessibleCache::removeCocoaElement(QAccessible::Id axid)
+{
+    QCocoaAccessibleElement *element = elementForId(axid);
+    [element invalidate];
+    cocoaElements.remove(axid);
+}
+
+QCocoaAccessibleElement *QAccessibleCache::elementForId(QAccessible::Id axid) const
+{
+    return cocoaElements.value(axid);
+}
+
+QT_END_NAMESPACE
+
+#endif