+ /**
+ * Callback for the wheel event when the wheel event occurs.
+ * @param[in] wheel The WheelEvent information
+ */
+ void OnWheelEvent(const WheelEvent& wheel);
+
+ /**
+ * Called when the window focus is changed.
+ * @param[in] window The window whose focus is changed
+ * @param[in] focusIn Whether the focus is in/out
+ */
+ void OnWindowFocusChanged(Window window, bool focusIn);
+
+ /**
+ * Get the focus Actor from current window
+ */
+ Actor GetFocusActorFromCurrentWindow();
+
+ /**
+ * 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 EmitCustomWheelSignals(Actor actor, const WheelEvent& event);
+
+ /**
+ * Clear the focus indicator actor.
+ */
+ void ClearFocusIndicator();
+
+private: