SimpleMenu.java

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


/**
A short example of a menu item and an action listener.
*/
class SimpleMenu extends JFrame
{
    // Just plop the main() method right in the frame class...
    public static void main(String argv[])
    {
        SimpleMenu f = new SimpleMenu();
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.show();
    }


    public SimpleMenu()
    {
        Toolkit kit = Toolkit.getDefaultToolkit();
        Dimension ss = kit.getScreenSize();
        setSize(ss.width/3,ss.height/6);
        setLocation(ss.width/4,ss.height/4);
        setTitle("CISC370-011 -- simple menu demo");

        ButtonPanel sp = new ButtonPanel();
        Container contentPane = getContentPane();
        contentPane.add(sp);

        JMenuBar mbar = new JMenuBar();
        setJMenuBar(mbar);
        JMenu fileMenu = new JMenu("File");
        mbar.add(fileMenu);
        JMenuItem exitItem = new JMenuItem("Exit");
        fileMenu.add(exitItem);
        exitItem.addActionListener(new ActionListener() {
                public void actionPerformed(ActionEvent e)
                    { System.exit(0); }
            });
    }
}


class ButtonPanel extends JPanel
{
    public ButtonPanel() {
        mkButton("Red",Color.RED);
        mkButton("Yellow",Color.YELLOW);
        mkButton("Green",Color.GREEN);    
    }


    void mkButton(String name,final Color bg) {
        JButton jb = new JButton(name);
        add(jb);
        jb.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e)
                { setBackground(bg); }
            });
    }
}