Let platform plugin decide if accessibility is active

Change-Id: I881a8ff3fedf3db73ee37046a4363c70960a92a6
Reviewed-by: Jan Arve Sæther <jan-arve.saether@digia.com>

src/3rdparty/atspi2/atspi2.pri

@@ -2,7 +2,7 @@
 DBUS_ADAPTORS = $$PWD/xml/Cache.xml $$PWD/xml/DeviceEventController.xml
 QDBUSXML2CPP_ADAPTOR_HEADER_FLAGS = -i struct_marshallers_p.h
 
-DBUS_INTERFACES = $$PWD/xml/Socket.xml
+DBUS_INTERFACES = $$PWD/xml/Socket.xml $$PWD/xml/Bus.xml
 QDBUSXML2CPP_INTERFACE_HEADER_FLAGS = -i struct_marshallers_p.h
 
 INCLUDEPATH += $$PWD

src/3rdparty/atspi2/xml/Bus.xml

@@ -0,0 +1,17 @@
+<!DOCTYPE node PUBLIC "-//freedesktop//DTD D-BUS Object Introspection 1.0//EN"
+                      "http://www.freedesktop.org/standards/dbus/1.0/introspect.dtd">
+<node>
+  <interface name="org.a11y.Status">
+    <property type="b" name="IsEnabled" access="readwrite">
+    </property>
+    <property type="b" name="ScreenReaderEnabled" access="readwrite">
+    </property>
+  </interface>
+  <interface name="org.a11y.Bus">
+    <method name="GetAddress">
+      <arg type="s" name="address" direction="out">
+      </arg>
+    </method>
+  </interface>
+</node>
+

src/gui/accessible/qaccessible.cpp

@@ -441,7 +441,6 @@ Q_GLOBAL_STATIC(QAccessiblePluginsHash, qAccessiblePlugins);
 QAccessible::UpdateHandler QAccessible::updateHandler = 0;
 QAccessible::RootObjectHandler QAccessible::rootObjectHandler = 0;
 
-static bool accessibility_active = false;
 static bool cleanupAdded = false;
 
 #ifndef QT_NO_ACCESSIBILITY
@@ -584,7 +583,6 @@ Q_GLOBAL_STATIC(QAccessibleCache, qAccessibleCache)
 */
 QAccessibleInterface *QAccessible::queryAccessibleInterface(QObject *object)
 {
-    accessibility_active = true;
     if (!object)
         return 0;
 
@@ -699,19 +697,26 @@ QAccessibleInterface *QAccessible::accessibleInterface(Id id)
 
 
 /*!
-    Returns true if an accessibility implementation has been requested
-    during the runtime of the application; otherwise returns false.
+    Returns true if the platform requested accessibility information.
 
-    Use this function to prevent potentially expensive notifications via
-    updateAccessibility().
+    This function will return false until a tool such as a screen reader
+    accessed the accessibility framework. It is still possible to use
+    \l QAccessible::queryAccessibleInterface even if accessibility is not
+    active. But there will be no notifications sent to the platform.
+
+    It is recommended to use this function to prevent expensive notifications
+    via updateAccessibility() when they are not needed.
 */
 bool QAccessible::isActive()
 {
-    return accessibility_active;
+#ifndef QT_NO_ACCESSIBILITY
+    if (QPlatformAccessibility *pfAccessibility = platformAccessibility())
+        return pfAccessibility->isActive();
+#endif
+    return false;
 }
 
 
-
 /*!
   Sets the root object of the accessible objects of this application
   to \a object.  All other accessible objects are reachable using object

src/gui/accessible/qplatformaccessibility.cpp

@@ -73,6 +73,7 @@ Q_GLOBAL_STATIC(QVector<QAccessibleBridge *>, bridges)
     \sa QAccessible
 */
 QPlatformAccessibility::QPlatformAccessibility()
+    : m_active(false)
 {
 }
 

src/gui/accessible/qplatformaccessibility.h

@@ -69,6 +69,11 @@ public:
     virtual void initialize();
     virtual void cleanup();
 
+    inline bool isActive() const { return m_active; }
+    inline void setActive(bool active) { m_active = active; }
+
+private:
+    bool m_active;
 };
 
 QT_END_NAMESPACE

src/platformsupport/linuxaccessibility/bridge.cpp

@@ -62,7 +62,7 @@ QT_BEGIN_NAMESPACE
 */
 
 QSpiAccessibleBridge::QSpiAccessibleBridge()
-    : cache(0), dec(0), dbusAdaptor(0), m_enabled(false)
+    : cache(0), dec(0), dbusAdaptor(0)
 {
     dbusConnection = new DBusConnection();
     connect(dbusConnection, SIGNAL(enabledChanged(bool)), this, SLOT(enabledChanged(bool)));
@@ -70,7 +70,7 @@ QSpiAccessibleBridge::QSpiAccessibleBridge()
 
 void QSpiAccessibleBridge::enabledChanged(bool enabled)
 {
-    m_enabled = enabled;
+    setActive(enabled);
     updateStatus();
 }
 
@@ -87,7 +87,7 @@ QDBusConnection QSpiAccessibleBridge::dBusConnection() const
 void QSpiAccessibleBridge::updateStatus()
 {
     // create the adaptor to handle everything if we are in enabled state
-    if (!dbusAdaptor && m_enabled) {
+    if (!dbusAdaptor && isActive()) {
         qSpiInitializeStructTypes();
         initializeConstantMappings();
 
@@ -106,7 +106,7 @@ void QSpiAccessibleBridge::notifyAccessibilityUpdate(QAccessibleEvent *event)
 {
     if (!dbusAdaptor)
         return;
-    if (m_enabled)
+    if (isActive())
         dbusAdaptor->notify(event);
 }
 

src/platformsupport/linuxaccessibility/bridge_p.h

@@ -76,7 +76,6 @@ private:
     DeviceEventControllerAdaptor *dec;
     AtSpiAdaptor *dbusAdaptor;
     DBusConnection* dbusConnection;
-    bool m_enabled;
 };
 
 QT_END_NAMESPACE

src/platformsupport/linuxaccessibility/dbusconnection.cpp

@@ -48,6 +48,7 @@
 #include <qdebug.h>
 
 #include <QDBusConnectionInterface>
+#include "bus_interface.h"
 
 QT_BEGIN_NAMESPACE
 
@@ -81,21 +82,24 @@ void DBusConnection::serviceRegistered()
 {
     // listen to enabled changes
     QDBusConnection c = QDBusConnection::sessionBus();
-    // FXIME check for changes of enabled state
-//    if (!c.connect(A11Y_SERVICE, A11Y_PATH, QStringLiteral("org.freedesktop.DBus.Properties"), QStringLiteral("PropertiesChanged"), this, SLOT(enabledStateChanged(QDBusVariant))))
-//        qWarning() << "Could not listen to accessibility enabled state changes.";
+    OrgA11yStatusInterface *a11yStatus = new OrgA11yStatusInterface(A11Y_SERVICE, A11Y_PATH, c, this);
 
-    // check if it's enabled right away
-    QDBusMessage enabledMessage = QDBusMessage::createMethodCall(A11Y_SERVICE, A11Y_PATH, QStringLiteral("org.freedesktop.DBus.Properties"), QStringLiteral("Get"));
-    QList<QVariant> args;
-    args << QStringLiteral("org.a11y.Status") << QStringLiteral("IsEnabled");
-    enabledMessage.setArguments(args);
-    c.callWithCallback(enabledMessage, this, SLOT(enabledStateCallback(QDBusVariant)), SLOT(dbusError(QDBusError)));
-}
+    // a11yStatus->isEnabled() returns always true (since Gnome 3.6)
+    bool enabled = a11yStatus->screenReaderEnabled();
+    if (enabled != m_enabled) {
+        m_enabled = enabled;
+        if (m_a11yConnection.isConnected()) {
+            emit enabledChanged(m_enabled);
+        } else {
+            QDBusConnection c = QDBusConnection::sessionBus();
+            QDBusMessage m = QDBusMessage::createMethodCall(QLatin1String("org.a11y.Bus"),
+                                                            QLatin1String("/org/a11y/bus"),
+                                                            QLatin1String("org.a11y.Bus"), QLatin1String("GetAddress"));
+            c.callWithCallback(m, this, SLOT(connectA11yBus(QString)), SLOT(dbusError(QDBusError)));
+        }
+    }
 
-void DBusConnection::dbusError(const QDBusError &error)
-{
-    qWarning() << "Accessibility encountered a DBus error:" << error;
+    //    connect(a11yStatus, ); QtDbus doesn't support notifications for property changes yet
 }
 
 void DBusConnection::serviceUnregistered()
@@ -103,20 +107,6 @@ void DBusConnection::serviceUnregistered()
     emit enabledChanged(false);
 }
 
-void DBusConnection::enabledStateCallback(const QDBusVariant &enabled)
-{
-    m_enabled = enabled.variant().toBool();
-    if (m_a11yConnection.isConnected()) {
-        emit enabledChanged(m_enabled);
-    } else {
-        QDBusConnection c = QDBusConnection::sessionBus();
-        QDBusMessage m = QDBusMessage::createMethodCall(QLatin1String("org.a11y.Bus"),
-                                                        QLatin1String("/org/a11y/bus"),
-                                                        QLatin1String("org.a11y.Bus"), QLatin1String("GetAddress"));
-        c.callWithCallback(m, this, SLOT(connectA11yBus(QString)), SLOT(dbusError(QDBusError)));
-    }
-}
-
 void DBusConnection::connectA11yBus(const QString &address)
 {
     if (address.isEmpty()) {
@@ -129,6 +119,11 @@ void DBusConnection::connectA11yBus(const QString &address)
         emit enabledChanged(true);
 }
 
+void DBusConnection::dbusError(const QDBusError &error)
+{
+    qWarning() << "Accessibility encountered a DBus error:" << error;
+}
+
 /*!
   Returns the DBus connection that got established.
   Or an invalid connection if not yet connected.

src/platformsupport/linuxaccessibility/dbusconnection_p.h

@@ -67,8 +67,6 @@ Q_SIGNALS:
 private Q_SLOTS:
     void serviceRegistered();
     void serviceUnregistered();
-    void enabledStateCallback(const QDBusVariant &enabled);
-//    void enabledStateChanged(const QDBusVariant &);
     void connectA11yBus(const QString &address);
 
     void dbusError(const QDBusError &error);

src/plugins/platforms/cocoa/qnsview.h

@@ -63,7 +63,6 @@ QT_END_NAMESPACE
     QWindow *m_window;
     QCocoaWindow *m_platformWindow;
     Qt::MouseButtons m_buttons;
-    QAccessibleInterface *m_accessibleRoot;
     QString m_composingText;
     bool m_sendKeyEvent;
     QStringList *currentCustomDragTypes;

src/plugins/platforms/cocoa/qnsview.mm

@@ -121,7 +121,6 @@ static QTouchDevice *touchDevice = 0;
 
     m_window = window;
     m_platformWindow = platformWindow;
-    m_accessibleRoot = 0;
     m_sendKeyEvent = false;
 
 #ifdef QT_COCOA_ENABLE_ACCESSIBILITY_INSPECTOR
@@ -130,15 +129,13 @@ static QTouchDevice *touchDevice = 0;
     static bool skipAccessibilityForInspectorWindows = false;
     if (!skipAccessibilityForInspectorWindows) {
 
-        m_accessibleRoot = window->accessibleRoot();
+        // m_accessibleRoot = window->accessibleRoot();
 
         AccessibilityInspector *inspector = new AccessibilityInspector(window);
         skipAccessibilityForInspectorWindows = true;
         inspector->inspectWindow(window);
         skipAccessibilityForInspectorWindows = false;
     }
-#else
-    m_accessibleRoot = window->accessibleRoot();
 #endif
 
     [self registerDragTypes];

src/plugins/platforms/cocoa/qnsviewaccessibility.mm

@@ -45,6 +45,7 @@
 #include "qcocoahelpers.h"
 #include "qcocoaaccessibility.h"
 #include "qcocoaaccessibilityelement.h"
+#include <qpa/qplatformintegration.h>
 
 #include <QtGui/private/qaccessible2_p.h>
 #include <QtCore/QDebug>
@@ -60,22 +61,26 @@
 }
 
 - (id)accessibilityAttributeValue:(NSString *)attribute {
+
+    // activate accessibility updates
+    QGuiApplicationPrivate::platformIntegration()->accessibility()->setActive(true);
+
     if ([attribute isEqualToString:NSAccessibilityRoleAttribute]) {
-        if (m_accessibleRoot)
-            return QCocoaAccessible::macRole(m_accessibleRoot);
+        if (m_window->accessibleRoot())
+            return QCocoaAccessible::macRole(m_window->accessibleRoot());
         return NSAccessibilityUnknownRole;
     } else if ([attribute isEqualToString:NSAccessibilityRoleDescriptionAttribute]) {
         return NSAccessibilityRoleDescriptionForUIElement(self);
     } else if ([attribute isEqualToString:NSAccessibilityChildrenAttribute]) {
-        if (!m_accessibleRoot)
+        if (!m_window->accessibleRoot())
             return [super accessibilityAttributeValue:attribute];
 
         // Create QCocoaAccessibleElements for each child if the
         // root accessible interface.
-        int numKids = m_accessibleRoot->childCount();
+        int numKids = m_window->accessibleRoot()->childCount();
         NSMutableArray *kids = [NSMutableArray arrayWithCapacity:numKids];
         for (int i = 0; i < numKids; ++i) {
-            QAccessibleInterface *child = m_accessibleRoot->child(i);
+            QAccessibleInterface *child = m_window->accessibleRoot()->child(i);
             Q_ASSERT(child);
             QAccessible::Id childAxid = QAccessible::uniqueId(child);
             QCocoaAccessibleElement *element = [QCocoaAccessibleElement createElementWithId:childAxid parent:self];
@@ -90,10 +95,10 @@
 }
 
 - (id)accessibilityHitTest:(NSPoint)point {
-    if (!m_accessibleRoot)
+    if (!m_window->accessibleRoot())
         return [super accessibilityHitTest:point];
 
-    QAccessibleInterface *childInterface = m_accessibleRoot->childAt(point.x, qt_mac_flipYCoordinate(point.y));
+    QAccessibleInterface *childInterface = m_window->accessibleRoot()->childAt(point.x, qt_mac_flipYCoordinate(point.y));
     // No child found, meaning we hit the NSView
     if (!childInterface) {
         return [super accessibilityHitTest:point];

src/plugins/platforms/windows/accessible/qwindowsaccessibility.cpp

@@ -52,7 +52,9 @@
 #include <QtCore/qsettings.h>
 #include <QtGui/qaccessible.h>
 #include <QtGui/private/qaccessible2_p.h>
+#include <QtGui/private/qguiapplication_p.h>
 #include <qpa/qplatformnativeinterface.h>
+#include <qpa/qplatformintegration.h>
 #include <QtGui/qwindow.h>
 #include <QtGui/qguiapplication.h>
 
@@ -245,6 +247,8 @@ bool QWindowsAccessibility::handleAccessibleObjectFromWindowRequest(HWND hwnd, W
     if (static_cast<long>(lParam) == static_cast<long>(UiaRootObjectId)) {
         /* For UI Automation */
     } else if ((DWORD)lParam == DWORD(OBJID_CLIENT)) {
+        // Start handling accessibility internally
+        QGuiApplicationPrivate::platformIntegration()->accessibility()->setActive(true);
 #if 1
         // Ignoring all requests while starting up
         // ### Maybe QPA takes care of this???

tests/auto/other/qaccessibility/qaccessibility.pro

@@ -1,7 +1,7 @@
 CONFIG += testcase
 TARGET = tst_qaccessibility
 requires(contains(QT_CONFIG,accessibility))
-QT += testlib gui-private widgets-private
+QT += testlib core-private gui-private widgets-private
 SOURCES  += tst_qaccessibility.cpp
 
 unix:!mac:LIBS+=-lm

tests/auto/other/qaccessibility/tst_qaccessibility.cpp

@@ -63,6 +63,9 @@
 #include <QtWidgets/private/qaccessiblewidget_p.h>
 #include <math.h>
 #include <qpa/qplatformnativeinterface.h>
+#include <qpa/qplatformintegration.h>
+#include <qpa/qplatformaccessibility.h>
+#include <QtGui/private/qguiapplication_p.h>
 
 #if defined(Q_OS_WIN) && defined(interface)
 #   undef interface
@@ -311,6 +314,8 @@ void tst_QAccessibility::onClicked()
 void tst_QAccessibility::initTestCase()
 {
     QTestAccessibility::initialize();
+    QPlatformIntegration *pfIntegration = QGuiApplicationPrivate::platformIntegration();
+    pfIntegration->accessibility()->setActive(true);
 }
 
 void tst_QAccessibility::cleanupTestCase()

tests/auto/other/qaccessibilitylinux/tst_qaccessibilitylinux.cpp

@@ -55,6 +55,7 @@
 #include <QDBusReply>
 
 #include "atspi/atspi-constants.h"
+#include "bus_interface.h"
 
 #include "dbusconnection_p.h"
 #include "struct_marshallers_p.h"
@@ -154,16 +155,21 @@ QDBusInterface *tst_QAccessibilityLinux::getInterface(const QString &path, const
     return new QDBusInterface(address, path, interfaceName, dbus.connection(), this);
 }
 
-
 void tst_QAccessibilityLinux::initTestCase()
 {
     // Oxygen style creates many extra items, it's simply unusable here
     qApp->setStyle("fusion");
     qApp->setApplicationName("tst_QAccessibilityLinux app");
 
+    // Pretend we are a screen reader
+    QDBusConnection c = QDBusConnection::sessionBus();
+    OrgA11yStatusInterface *a11yStatus = new OrgA11yStatusInterface(QStringLiteral("org.a11y.Bus"), QStringLiteral("/org/a11y/bus"), c, this);
+    a11yStatus->setScreenReaderEnabled(true);
+
     QTRY_VERIFY(dbus.isEnabled());
     QTRY_VERIFY(dbus.connection().isConnected());
     address = dbus.connection().baseService().toLatin1().data();
+    QVERIFY(!address.isEmpty());
 
     m_window = new AccessibleTestWindow();
     m_window->show();