Listing 6. WindowBar Widget

import java.awt.event.* ;
import java.awt.* ;
import java.net.* ;
public class  WindowBar extends Panel implements 
	ActionListener 
	{
	public WindowBar() {
		super() ;
		_closer = new Button( 
		"Collapse" ) ;
		_closer.addActionListener( this );
		//setLayout( new BorderLayout() );
		//add( "East", _closer );
		Panel p = new Panel() ;
		p.add( _closer ) ;
		add( p ) ;
	}
	public void addCollapseListener( 
		PaneSwitchListener l )
		{
		_collapseListener = 
			MyMulticaster.add( 
			_collapseListener, l ) ; 
	}
	public void actionPerformed( ActionEvent e )
		{
		if ( _collapseListener == null ) 
			return ; 
		if ( _collapsed ) {
			_collapseListener.restore( 
			 new PaneSwitchEvent( this,
			 PaneSwitchEvent.RESTORE ));
			_closer.setLabel( 
			 "Collapse" ) ;
		} else {
			_collapseListener.collapse(
			 new PaneSwitchEvent( this,
			 PaneSwitchEvent.COLLAPSE ));
			_closer.setLabel( 
			 "restore" ) ;
		}
		_collapsed = !_collapsed ;	
	}
	private boolean _collapsed = false ;
	private PaneSwitchListener _collapseListener
		= null ;
	private Button _closer ;
}