Cocoa: Add initial accessibility implementation.

See qcocoaaccessiblity.h for details.

For now only the first level of the hierarchy is
made accessible.

Also add tools/accessibilityinspector which is an
utility for inspecting and debugging the Qt
accessibility tree.

Change-Id: Iff520bec26b3761feb0c2e00471feb379daaa735
Reviewed-by: Morten Johan Sørvig <morten.sorvig@nokia.com>

1 files changed, 117 insertions, 0 deletions

diff --git a/src/plugins/platforms/cocoa/qnsviewaccessibility.mm b/src/plugins/platforms/cocoa/qnsviewaccessibility.mm
new file mode 100644
index 0000000000..327bace123
--- /dev/null
+++ b/src/plugins/platforms/cocoa/qnsviewaccessibility.mm
@@ -0,0 +1,117 @@
+/****************************************************************************
+**
+** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the plugins of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** GNU Lesser General Public License Usage
+** 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, Nokia gives you certain additional
+** rights. These rights are described in the Nokia 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.
+**
+** Other Usage
+** Alternatively, this file may be used in accordance with the terms and
+** conditions contained in a signed written agreement between you and Nokia.
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <Carbon/Carbon.h>
+
+#include "qnsview.h"
+#include "qcocoahelpers.h"
+#include "qcocoaaccessibility.h"
+#include "qcocoaaccessibilityelement.h"
+
+#include "QAccessibleActionInterface"
+#include <QtCore/QDebug>
+
+#import <AppKit/NSAccessibility.h>
+
+@implementation QNSView (QNSViewAccessibility)
+
+- (BOOL)accessibilityIsIgnored {
+    return NO;
+}
+
+- (id)accessibilityAttributeValue:(NSString *)attribute {
+    if ([attribute isEqualToString:NSAccessibilityRoleAttribute]) {
+        if (m_accessibleRoot)
+            return macRole(m_accessibleRoot->role());
+        return NSAccessibilityUnknownRole;
+    } else if ([attribute isEqualToString:NSAccessibilityRoleDescriptionAttribute]) {
+        return NSAccessibilityRoleDescriptionForUIElement(self);
+    } else if ([attribute isEqualToString:NSAccessibilityChildrenAttribute]) {
+        if (!m_accessibleRoot)
+            return [super accessibilityAttributeValue:attribute];
+
+        // Create QCocoaAccessibleElements for each child if the
+        // root accessible interface.
+        int numKids = m_accessibleRoot->childCount();
+        NSMutableArray *kids = [NSMutableArray arrayWithCapacity:numKids];
+        for (int i = 0; i < numKids; ++i) {
+            [kids addObject:[QCocoaAccessibleElement elementWithIndex:i parent:self accessibleInterface:(void*)m_accessibleRoot->child(i)]];
+        }
+
+        return NSAccessibilityUnignoredChildren(kids);
+    } else {
+        return [super accessibilityAttributeValue:attribute];
+    }
+}
+
+- (id)accessibilityHitTest:(NSPoint)point {
+    NSPoint windowPoint = [[self window] convertScreenToBase:point];
+    NSPoint localPoint = [self convertPoint:windowPoint fromView:nil];
+
+    int index = -1;
+    if (m_accessibleRoot) {
+        index = m_accessibleRoot->childAt(point.x, qt_mac_flipYCoordinate(point.y));
+
+        // qDebug() << "root rect" << m_accessibleRoot->rect();
+        // qDebug() << "hit screen" << point.x << qt_mac_flipYCoordinate(point.y)  << index;
+        // if (index > 0) {
+        //      qDebug() << "child name" << m_accessibleRoot->child(index - 1)->text(QAccessible::Name);
+        //      qDebug() << "child rect" << m_accessibleRoot->child(index - 1)->rect();
+        // }
+    }
+
+    // hit outside
+    if (index == -1) {
+        return [super accessibilityHitTest:point];
+    }
+
+    // hit the NSView / top-level window
+    if (index == 0) {
+        QCocoaAccessibleElement *accessibleElement = [QCocoaAccessibleElement elementWithIndex:index parent:self accessibleInterface:(void*)m_accessibleRoot];
+        return [accessibleElement accessibilityHitTest:point];
+    }
+
+    // hit a child, forward to child accessible interface.
+    QCocoaAccessibleElement *accessibleElement = [QCocoaAccessibleElement elementWithIndex:index - 1 parent:self accessibleInterface:(void*)m_accessibleRoot->child(index -1)];
+    return [accessibleElement accessibilityHitTest:point];
+}
+
+@end