layout();
layout(false);
public void setTopLeft(Control c) {	checkWidget();	if (c != null && c.getParent() != this) {		SWT.error(SWT.ERROR_INVALID_ARGUMENT);	}	if (this.topLeft != null && !this.topLeft.isDisposed()) {		Point size = this.topLeft.getSize();		this.topLeft.setLocation(OFFSCREEN - size.x, OFFSCREEN - size.y);	}	this.topLeft = c;	layout();}