/* Copyright (C) 2002 J. M. Spivey */

import java.applet.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

/** Common class for demo applets.
 * 
 * Displays a launch button on the web page, and 
 * creates a separate applet window when it is pressed.
 */
public class DemoApplet extends JApplet {
    private String name;
    private DemoFrame frame = null;
    
    /** Create or redisplay a frame in response to a button press */
    private void createFrame() {
        if (frame != null)
            frame.toFront();
        else {
            try {
                Class appClass = Class.forName(name);
                frame = (DemoFrame) appClass.newInstance();
                frame.initApplet(this);         
                frame.addWindowListener(new WindowAdapter() {
                    public void WindowOpened(WindowEvent e) { 
			frame.toFront(); 
		    }
                });
                frame.setVisible(true);
            }
            catch (Exception e) { System.out.println(e); }
        } 
    }
    
    public DemoFrame getFrame() { 
        if (frame == null) createFrame();
        return frame; 
    }
    
    public void forgetFrame() {
        frame = null;
    }
    
    public void init() {
	Color bg = new Color(0xcc, 0xcc, 0xee);
        setLayout(new BorderLayout()); 
        name = getParameter("name");
        JButton launch = new JButton("Launch " + name);
	launch.setFont(new Font("Sans", Font.BOLD, 12));
	launch.setBackground(bg);
        launch.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) { createFrame(); }
        });
        add(launch, "Center");
    }
    
    public void stop() {
        if (frame != null) frame.die();
    }   
}