Called when mouse enter this Element. This function is meant to be overriden. Between onMouseEnter and onMouseExit, isMouseOver will return true.
use this callback to call setDirtyWhole so that you can draw a highlight when the widget is pointed to.
See Implementation
Called when mouse enter this Element. This function is meant to be overriden. Between onMouseEnter and onMouseExit, isMouseOver will return true.