/* * Beeper.java requires no other files. */ import java.awt.*; import javax.swing.JFrame; import javax.swing.JPanel; import javax.swing.JButton; import javax.swing.JComponent; import java.awt.Toolkit; import java.awt.BorderLayout; import java.awt.event.ActionListener; import java.awt.event.ActionEvent; public class Beeper extends JPanel implements ActionListener { JButton button; public Beeper() { super(new BorderLayout()); button = new JButton("Click Me"); button.setPreferredSize(new Dimension(200, 80)); add(button, BorderLayout.CENTER); button.addActionListener(this); } public void actionPerformed(ActionEvent e) { Toolkit.getDefaultToolkit().beep(); } /** * Create the GUI and show it. For thread safety, * this method should be invoked from the * event-dispatching thread. */ private static void createAndShowGUI() { //Create and set up the window. JFrame frame = new JFrame("Beeper"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); //Create and set up the content pane. JComponent newContentPane = new Beeper(); newContentPane.setOpaque(true); //content panes must be opaque frame.setContentPane(newContentPane); //Display the window. frame.pack(); frame.setVisible(true); } public static void main(String[] args) { //Schedule a job for the event-dispatching thread: //creating and showing this application's GUI. javax.swing.SwingUtilities.invokeLater(new Runnable() { public void run() { createAndShowGUI(); } }); } }