public void addElement( DesignElementHandle child, int slotId )
public void addElement( DesignElementHandle child, int slotId, int pos )
	public void addElement( DesignElementHandle child, int slotId )			throws ContentException, NameException	{		SlotHandle slotHandle = getSlot( slotId );		if ( slotHandle != null )			slotHandle.add( child );	}