if (columnCount != 0) {
if (columnCount != 0 || scrollWidth != 0) {
void updateScrollBar () {	if (hwndParent != 0) {		int columnCount = OS.SendMessage (hwndHeader, OS.HDM_GETITEMCOUNT, 0, 0);		if (columnCount != 0) {			SCROLLINFO info = new SCROLLINFO ();			info.cbSize = SCROLLINFO.sizeof;			info.fMask = OS.SIF_ALL;			int itemCount = OS.SendMessage (handle, OS.TVM_GETCOUNT, 0, 0);			if (itemCount == 0) {				OS.GetScrollInfo (hwndParent, OS.SB_VERT, info);				info.nPage = info.nMax + 1;				OS.SetScrollInfo (hwndParent, OS.SB_VERT, info, true);			} else {				OS.GetScrollInfo (handle, OS.SB_VERT, info);				OS.SetScrollInfo (hwndParent, OS.SB_VERT, info, true);			}		}	}}