+ /**
+ * Recursively deliver events to the control and its parents, until the event is consumed or the stage is reached.
+ * @param[in] actor The actor got WheelEvent.
+ * @param[in] event The WheelEvent.
+ * @return True if WheelEvent is consumed.
+ */
+ bool EmitWheelSignals(Actor actor, const WheelEvent& event);
+