protected override bool GetHitTest(Point point)
        {
            // if mouse is over node, columns or scrollbar then return true
            // which will cause the mouse event to be forwarded to the control
            TreeListView tree = Control as TreeListView;

            point = tree.PointToClient(point);

            Node node = tree.CalcHitNode(point);

            if (node != null)
            {
                return(true);
            }

            TreelistView.HitInfo colinfo = tree.CalcColumnHit(point);
            if ((int)(colinfo.HitType & HitInfo.eHitType.kColumnHeader) > 0)
            {
                return(true);
            }

            if (tree.HitTestScrollbar(point))
            {
                return(true);
            }
            return(base.GetHitTest(point));
        }