     }
 
     /**
+     *  @private
      *  Handle mouse-up events anywhere on or off the stage.
      */
     protected function system_mouseUpHandler(event:MouseEvent):void

        invalidateSkinState();
    }
    
    override public function set maximum(value:Number):void
    {
        super.maximum = value;
        invalidateDisplayList();
    }

    override public function set minimum(value:Number):void
    {
        super.minimum = value;
        invalidateDisplayList();
    }
    
    override public function set value(newValue:Number):void
    {
        super.value = newValue;
        invalidateDisplayList();
    }
    
    override protected function setValue(value:Number):void
    {
        super.setValue(value);

    private var _clickOffset:Point;
    
    /**
     *  The point in the local coordinates of 
     *  the thumb button where the last mouse down event occurred. 
     *  This property is used by the <code>calculateNewValue()</code> method 
     *  to determine the value that the thumb button has been dragged to.
     *
     *  @return Point object rerpresenting, in the local coordinates of 
     *  the thumb button, where the last mouse down event occurred. 
     */
    protected function get clickOffset():Point
    {
