OS X Accessibility: Make checkboxes etc. checkable with VoiceOver

NSAccessibility has no explicit analog for
QAccessibleActionInterface::toggleAction(), checking checkboxes/radio
buttons is handled by NSAccessibilityPressAction. So ensure exposing
the action properly on OS X so that VoiceOver users can check/uncheck
checkboxes, select radio buttons etc.

Change-Id: Idc8b048de2313a3e875a929516baf3dded9c68cc
Task-number: QTBUG-44852
Reviewed-by: Jan Arve Sæther <jan-arve.saether@theqtcompany.com>

src/plugins/platforms/cocoa/qcocoaaccessibility.h

@@ -77,7 +77,7 @@ bool shouldBeIgnored(QAccessibleInterface *interface);
 NSArray *unignoredChildren(QAccessibleInterface *interface);
 NSString *getTranslatedAction(const QString &qtAction);
 NSMutableArray *createTranslatedActionsList(const QStringList &qtActions);
-QString translateAction(NSString *nsAction);
+QString translateAction(NSString *nsAction, QAccessibleInterface *interface);
 bool hasValueAttribute(QAccessibleInterface *interface);
 id getValueAttribute(QAccessibleInterface *interface);
 

src/plugins/platforms/cocoa/qcocoaaccessibility.mm

@@ -284,6 +284,8 @@ NSString *getTranslatedAction(const QString &qtAction)
         return NSAccessibilityShowMenuAction;
     else if (qtAction == QAccessibleActionInterface::setFocusAction()) // Not 100% sure on this one
         return NSAccessibilityRaiseAction;
+    else if (qtAction == QAccessibleActionInterface::toggleAction())
+        return NSAccessibilityPressAction;
 
     // Not translated:
     //
@@ -305,11 +307,13 @@ NSString *getTranslatedAction(const QString &qtAction)
     Translates between a Mac action constant and a QAccessibleActionInterface action
     Returns an empty QString if there is no Qt predefined equivalent.
 */
-QString translateAction(NSString *nsAction)
+QString translateAction(NSString *nsAction, QAccessibleInterface *interface)
 {
-    if ([nsAction compare: NSAccessibilityPressAction] == NSOrderedSame)
+    if ([nsAction compare: NSAccessibilityPressAction] == NSOrderedSame) {
+        if (interface->role() == QAccessible::CheckBox || interface->role() == QAccessible::RadioButton)
+            return QAccessibleActionInterface::toggleAction();
         return QAccessibleActionInterface::pressAction();
-    else if ([nsAction compare: NSAccessibilityIncrementAction] == NSOrderedSame)
+    } else if ([nsAction compare: NSAccessibilityIncrementAction] == NSOrderedSame)
         return QAccessibleActionInterface::increaseAction();
     else if ([nsAction compare: NSAccessibilityDecrementAction] == NSOrderedSame)
         return QAccessibleActionInterface::decreaseAction();

src/plugins/platforms/cocoa/qcocoaaccessibilityelement.mm

@@ -501,7 +501,7 @@ static void convertLineOffset(QAccessibleTextInterface *text, int &line, int &of
     QAccessibleInterface *iface = QAccessible::accessibleInterface(axid);
     if (!iface)
         return nil; // FIXME is that the right return type??
-    QString qtAction = QCocoaAccessible::translateAction(action);
+    QString qtAction = QCocoaAccessible::translateAction(action, iface);
     QString description;
     // Return a description from the action interface if this action is not known to the OS.
     if (qtAction.isEmpty()) {
@@ -518,7 +518,7 @@ static void convertLineOffset(QAccessibleTextInterface *text, int &line, int &of
 - (void)accessibilityPerformAction:(NSString *)action {
     QAccessibleInterface *iface = QAccessible::accessibleInterface(axid);
     if (iface) {
-        const QString qtAction = QCocoaAccessible::translateAction(action);
+        const QString qtAction = QCocoaAccessible::translateAction(action, iface);
         QAccessibleBridgeUtils::performEffectiveAction(iface, qtAction);
     }
 }

tests/auto/other/qaccessibilitymac/tst_qaccessibilitymac.cpp

@@ -75,6 +75,7 @@ private slots:
     void lineEditTest();
     void hierarchyTest();
     void notificationsTest();
+    void checkBoxTest();
 
 private:
     AccessibleTestWindow *m_window;
@@ -151,5 +152,19 @@ void tst_QAccessibilityMac::notificationsTest()
     QVERIFY(notifications(m_window));
 }
 
+void tst_QAccessibilityMac::checkBoxTest()
+{
+    if (!macNativeAccessibilityEnabled())
+        return;
+
+    QCheckBox *cb = new QCheckBox(m_window);
+    cb->setText("Great option");
+    m_window->addWidget(cb);
+    QVERIFY(QTest::qWaitForWindowExposed(m_window));
+    QCoreApplication::processEvents();
+
+    QVERIFY(testCheckBox());
+}
+
 QTEST_MAIN(tst_QAccessibilityMac)
 #include "tst_qaccessibilitymac.moc"

tests/auto/other/qaccessibilitymac/tst_qaccessibilitymac_helpers.h

@@ -44,3 +44,4 @@ bool testLineEdit();
 bool testHierarchy(QWidget *w);
 bool singleWidget();
 bool notifications(QWidget *w);
+bool testCheckBox();

tests/auto/other/qaccessibilitymac/tst_qaccessibilitymac_helpers.mm

@@ -114,6 +114,7 @@ QDebug operator<<(QDebug dbg, AXErrorTag err)
     @property (readonly) NSString *description;
     @property (readonly) NSString *value;
     @property (readonly) CGRect rect;
+    @property (readonly) NSArray *actions;
 @end
 
 @implementation TestAXObject
@@ -329,10 +330,34 @@ QDebug operator<<(QDebug dbg, AXErrorTag err)
     return value;
 }
 
+- (NSArray*)actions
+{
+    AXError err;
+    CFArrayRef actions;
+
+    if (kAXErrorSuccess != (err = AXUIElementCopyActionNames(reference, &actions)))
+    {
+        qDebug() << "AXUIElementCopyActionNames(...) returned error = " << AXErrorTag(err);
+    }
+
+    return (NSArray*)actions;
+}
+
+- (void)performAction:(CFStringRef)action
+{
+    AXError err;
+
+    if (kAXErrorSuccess != (err = AXUIElementPerformAction(reference, action)))
+    {
+        qDebug() << "AXUIElementPerformAction("  << QString::fromCFString(action) << ") returned error = " << AXErrorTag(err);
+    }
+}
+
 - (NSString*)           role { return [self _stringAttributeValue:kAXRoleAttribute]; }
 - (NSString*)           title { return [self _stringAttributeValue:kAXTitleAttribute]; }
 - (NSString*)           description { return [self _stringAttributeValue:kAXDescriptionAttribute]; }
 - (NSString*)           value { return [self _stringAttributeValue:kAXValueAttribute]; }
+- (NSInteger)           valueNumber { return [self _numberAttributeValue:kAXValueAttribute]; }
 - (NSRect)              rect
 {
     NSRect rect;
@@ -563,3 +588,37 @@ bool notifications(QWidget *w)
 
     return true;
 }
+
+bool testCheckBox()
+{
+    TestAXObject *appObject = [TestAXObject getApplicationAXObject];
+    EXPECT(appObject);
+
+    NSArray *windowList = [appObject windowList];
+    // one window
+    EXPECT([windowList count] == 1);
+    AXUIElementRef windowRef = (AXUIElementRef) [windowList objectAtIndex: 0];
+    EXPECT(windowRef != nil);
+    TestAXObject *window = [[TestAXObject alloc] initWithAXUIElementRef: windowRef];
+
+    // children of window:
+    AXUIElementRef checkBox = [window findDirectChildByRole: kAXCheckBoxRole];
+    EXPECT(checkBox != nil);
+
+    TestAXObject *cb = [[TestAXObject alloc] initWithAXUIElementRef: checkBox];
+
+    // here start actual checkbox tests
+    EXPECT([cb valueNumber] == 0);
+    EXPECT([cb.title isEqualToString:@"Great option"]);
+    // EXPECT(cb.description == nil); // currently returns "" instead of nil
+
+    EXPECT([cb.actions containsObject:(NSString*)kAXPressAction]);
+
+    [cb performAction:kAXPressAction];
+    EXPECT([cb valueNumber] == 1);
+
+    [cb performAction:kAXPressAction];
+    EXPECT([cb valueNumber] == 0);
+
+    return true;
+}