public void onClick( ClickEvent sender ) {
final AttributeCol52 clonedAt = at.cloneColumn();
at.setUseRowNumber( useRowNumber.getValue() );
reverseOrder.setEnabled( useRowNumber.getValue() );
dtable.updateSystemControlledColumnValues();
fireUpdateColumn( identity.getName(), clonedAt, at, clonedAt.diff( at ) );
}
} );
reverseOrder.addClickHandler( new ClickHandler() {
public void onClick( ClickEvent sender ) {