Enable touch events on Mac for PinchArea

Enabling touch events on a window causes scroll event
lag so we want to avoid avoid it as far as possible.

Enable/disable on scene changes, similar to what we do with
WA_AcceptTouchEvents for widgets, and in change
I2e5b5e2b093cccfc5253f7228f5ec0c588c60371 for MultiPointTouchArea.

Change-Id: I8cd8d172ffd93cfc4ec115917cc8662202f3b069
Reviewed-by: Gabriel de Dietrich <gabriel.dedietrich@digia.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/src/quick/items/qquickpincharea_p.h b/src/quick/items/qquickpincharea_p.h
index 4fc77d7f9c..60c2dc742e 100644
--- a/src/quick/items/qquickpincharea_p.h
+++ b/src/quick/items/qquickpincharea_p.h
@@ -283,12 +283,16 @@ protected:
                                  const QRectF &oldGeometry);
     virtual void itemChange(ItemChange change, const ItemChangeData& value);
 
+private slots:
+    void setTouchEventsEnabledForWindow(QWindow *window);
+
 private:
     void updatePinch();
     void handlePress();
     void handleRelease();
 
 private:
+    QWindow *_currentWindow;
     Q_DISABLE_COPY(QQuickPinchArea)
     Q_DECLARE_PRIVATE(QQuickPinchArea)
 };