checkWidget ();
void setSortDirection (int direction) {	checkWidget ();	if (OS.COMCTL32_MAJOR >= 6) {		int hwndHeader = parent.hwndHeader;		if (hwndHeader != 0) {			int index = parent.indexOf (this);			if (index == -1) return;			HDITEM hdItem = new HDITEM ();			hdItem.mask = OS.HDI_FORMAT | OS.HDI_IMAGE;			OS.SendMessage (hwndHeader, OS.HDM_GETITEM, index, hdItem);			switch (direction) {				case SWT.UP:					hdItem.fmt &= ~OS.HDF_IMAGE;					hdItem.fmt |= OS.HDF_SORTUP;					break;				case SWT.DOWN:					hdItem.fmt &= ~OS.HDF_IMAGE;					hdItem.fmt |= OS.HDF_SORTDOWN;					break;				case SWT.NONE:					hdItem.fmt &= ~(OS.HDF_SORTUP | OS.HDF_SORTDOWN);					if (image != null) {						hdItem.fmt |= OS.HDF_IMAGE;						hdItem.iImage = parent.imageIndex (image);					} else {						hdItem.fmt &= ~OS.HDF_IMAGE;					}					break;			}			OS.SendMessage (hwndHeader, OS.HDM_SETITEM, index, hdItem);		}	} else {		switch (direction) {			case SWT.UP:			case SWT.DOWN:				setImage (display.getSortImage (direction), true, true);				break;			case SWT.NONE:				setImage (image, false, false);				break;		}	}}