Fixes a crash when destroying and creating QApplication.

Moved the gestureManager pointer to a QApplicationPrivate to make sure if
QApplication object is destroyed, QGestureManager pointer is set to zero.

Task-number: QTBUG-7029
Reviewed-by: Thiago
(cherry picked from commit 828b1299e1ecb2da23799a2e49370e00dcf9c126)

5 files changed, 21 insertions, 19 deletions

diff --git a/src/gui/graphicsview/qgraphicsscene.cpp b/src/gui/graphicsview/qgraphicsscene.cpp
index 16ce26a..83ef110 100644
--- a/src/gui/graphicsview/qgraphicsscene.cpp
+++ b/src/gui/graphicsview/qgraphicsscene.cpp
@@ -1136,8 +1136,9 @@ bool QGraphicsScenePrivate::filterEvent(QGraphicsItem *item, QEvent *event)
 bool QGraphicsScenePrivate::sendEvent(QGraphicsItem *item, QEvent *event)
 {
     if (QGraphicsObject *object = item->toGraphicsObject()) {
-        if (qt_gestureManager) {
-            if (qt_gestureManager->filterEvent(object, event))
+        QGestureManager *gestureManager = QApplicationPrivate::instance()->gestureManager;
+        if (gestureManager) {
+            if (gestureManager->filterEvent(object, event))
                 return true;
         }
     }
@@ -6157,9 +6158,10 @@ void QGraphicsScenePrivate::cancelGesturesForChildren(QGesture *original, QWidge
         }
     }
 
-    Q_ASSERT(qt_gestureManager); // it would be very odd if we got called without a manager.
+    QGestureManager *gestureManager = QApplicationPrivate::instance()->gestureManager;
+    Q_ASSERT(gestureManager); // it would be very odd if we got called without a manager.
     for (setIter = canceledGestures.begin(); setIter != canceledGestures.end(); ++setIter) {
-        qt_gestureManager->recycle(*setIter);
+        gestureManager->recycle(*setIter);
         gestureTargets.remove(*setIter);
     }
 }
diff --git a/src/gui/kernel/qapplication.cpp b/src/gui/kernel/qapplication.cpp
index df36466..fb923be 100644
--- a/src/gui/kernel/qapplication.cpp
+++ b/src/gui/kernel/qapplication.cpp
@@ -177,6 +177,7 @@ QApplicationPrivate::QApplicationPrivate(int &argc, char **argv, QApplication::T
     directPainters = 0;
 #endif
 
+    gestureManager = 0;
     gestureWidget = 0;
 
     if (!self)
@@ -3632,7 +3633,7 @@ bool QApplication::notify(QObject *receiver, QEvent *e)
     }
 
     // walk through parents and check for gestures
-    if (qt_gestureManager) {
+    if (d->gestureManager) {
         switch (e->type()) {
         case QEvent::Paint:
         case QEvent::MetaCall:
@@ -3664,13 +3665,13 @@ bool QApplication::notify(QObject *receiver, QEvent *e)
             break;
         default:
             if (receiver->isWidgetType()) {
-                if (qt_gestureManager->filterEvent(static_cast<QWidget *>(receiver), e))
+                if (d->gestureManager->filterEvent(static_cast<QWidget *>(receiver), e))
                     return true;
             } else {
                 // a special case for events that go to QGesture objects.
                 // We pass the object to the gesture manager and it'll figure
                 // out if it's QGesture or not.
-                if (qt_gestureManager->filterEvent(receiver, e))
+                if (d->gestureManager->filterEvent(receiver, e))
                     return true;
             }
         }
@@ -5678,6 +5679,14 @@ Q_GUI_EXPORT void qt_translateRawTouchEvent(QWidget *window,
     QApplicationPrivate::translateRawTouchEvent(window, deviceType, touchPoints);
 }
 
+QGestureManager* QGestureManager::instance()
+{
+    QApplicationPrivate *qAppPriv = QApplicationPrivate::instance();
+    if (!qAppPriv->gestureManager)
+        qAppPriv->gestureManager = new QGestureManager(qApp);
+    return qAppPriv->gestureManager;
+}
+
 QT_END_NAMESPACE
 
 #include "moc_qapplication.cpp"
diff --git a/src/gui/kernel/qapplication_p.h b/src/gui/kernel/qapplication_p.h
index b004f95..e865399 100644
--- a/src/gui/kernel/qapplication_p.h
+++ b/src/gui/kernel/qapplication_p.h
@@ -84,6 +84,7 @@ class QInputContext;
 class QObject;
 class QWidget;
 class QSocketNotifier;
+class QGestureManager;
 
 extern bool qt_is_gui_used;
 #ifndef QT_NO_CLIPBOARD
@@ -509,6 +510,7 @@ public:
     void sendSyntheticEnterLeave(QWidget *widget);
 #endif
 
+    QGestureManager *gestureManager;
     QWidget *gestureWidget;
 
     QMap<int, QWeakPointer<QWidget> > widgetForTouchPointId;
diff --git a/src/gui/kernel/qgesturemanager.cpp b/src/gui/kernel/qgesturemanager.cpp
index 4757656..a4604bf 100644
--- a/src/gui/kernel/qgesturemanager.cpp
+++ b/src/gui/kernel/qgesturemanager.cpp
@@ -67,15 +67,6 @@
 
 QT_BEGIN_NAMESPACE
 
-QGestureManager *qt_gestureManager = 0;
-
-QGestureManager* QGestureManager::instance()
-{
-    if (!qt_gestureManager)
-        qt_gestureManager = new QGestureManager(qApp);
-    return qt_gestureManager;
-}
-
 QGestureManager::QGestureManager(QObject *parent)
     : QObject(parent), state(NotGesture), m_lastCustomGestureId(0)
 {
diff --git a/src/gui/kernel/qgesturemanager_p.h b/src/gui/kernel/qgesturemanager_p.h
index 0e1f153..9c4658c 100644
--- a/src/gui/kernel/qgesturemanager_p.h
+++ b/src/gui/kernel/qgesturemanager_p.h
@@ -78,7 +78,7 @@ public:
     bool filterEvent(QGraphicsObject *receiver, QEvent *event);
 #endif //QT_NO_GRAPHICSVIEW
 
-    static QGestureManager* instance();
+    static QGestureManager* instance(); // declared in qapplication.cpp
 
     void cleanupCachedGestures(QObject *target, Qt::GestureType type);
 
@@ -142,8 +142,6 @@ private:
     void cancelGesturesForChildren(QGesture *originatingGesture);
 };
 
-extern QGestureManager *qt_gestureManager;
-
 QT_END_NAMESPACE
 
 #endif // QGESTUREMANAGER_P_H