abstraction.showPresentation();
showPresentation();
	public void actionPerformed(ActionEvent e)	{		String s = (String) e.getActionCommand();		try {		   int index = Integer.parseInt(s);		   switch (index) { 				case R_VISIBLE:					abstraction.showPresentation();					break;				case SAVE:					saveDisplayOptions();					break;				case GREY:				case RGB:				case HSB:					activateRenderingModel(index);					break;	   			   }		} catch(NumberFormatException nfe) {   			   throw nfe;  //just to be on the safe side...		} 	}