Let platform plugin decide if accessibility is active

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

3 files changed, 19 insertions, 8 deletions

diff --git a/src/gui/accessible/qaccessible.cpp b/src/gui/accessible/qaccessible.cpp
index 4fd595ed5a..18157f8e2f 100644
--- a/src/gui/accessible/qaccessible.cpp
+++ b/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
diff --git a/src/gui/accessible/qplatformaccessibility.cpp b/src/gui/accessible/qplatformaccessibility.cpp
index 2e36e5ac71..490fb7a407 100644
--- a/src/gui/accessible/qplatformaccessibility.cpp
+++ b/src/gui/accessible/qplatformaccessibility.cpp
@@ -73,6 +73,7 @@ Q_GLOBAL_STATIC(QVector<QAccessibleBridge *>, bridges)
     \sa QAccessible
 */
 QPlatformAccessibility::QPlatformAccessibility()
+    : m_active(false)
 {
 }
 
diff --git a/src/gui/accessible/qplatformaccessibility.h b/src/gui/accessible/qplatformaccessibility.h
index 26a22e492d..f86a9b6157 100644
--- a/src/gui/accessible/qplatformaccessibility.h
+++ b/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