import java.awt.*; import java.awt.event.*; import javax.swing.*; public class RadioButtonDemo extends JPanel { static JFrame frame; static String birdString = "Bird"; static String catString = "Cat"; static String dogString = "Dog"; static String rabbitString = "Rabbit"; static String pigString = "Pig"; JLabel picture; public RadioButtonDemo() { // Create the radio buttons. //XXX: In 1.0.2 only, must use FixedJRadioButton instead of //XXX: JRadioButton if you want mnemonics to work. //XXX: See ui/swing/workaround.html for details. JRadioButton birdButton = new JRadioButton(birdString); birdButton.setMnemonic('b'); birdButton.setActionCommand(birdString); birdButton.setSelected(true); JRadioButton catButton = new JRadioButton(catString); catButton.setMnemonic('c'); catButton.setActionCommand(catString); JRadioButton dogButton = new JRadioButton(dogString); dogButton.setMnemonic('d'); dogButton.setActionCommand(dogString); JRadioButton rabbitButton = new JRadioButton(rabbitString); rabbitButton.setMnemonic('r'); rabbitButton.setActionCommand(rabbitString); JRadioButton pigButton = new JRadioButton(pigString); pigButton.setMnemonic('p'); pigButton.setActionCommand(pigString); // Group the radio buttons. ButtonGroup group = new ButtonGroup(); group.add(birdButton); group.add(catButton); group.add(dogButton); group.add(rabbitButton); group.add(pigButton); // Register a listener for the radio buttons. RadioListener myListener = new RadioListener(); birdButton.addActionListener(myListener); catButton.addActionListener(myListener); dogButton.addActionListener(myListener); rabbitButton.addActionListener(myListener); pigButton.addActionListener(myListener); // Set up the picture label picture = new JLabel(new ImageIcon("images/" + birdString + ".gif")); // The preferred size is hard-coded to be the width of the // widest image and the height of the tallest image. // A real program would compute this. picture.setPreferredSize(new Dimension(177, 122)); // Put the radio buttons in a column in a panel JPanel radioPanel = new JPanel(); radioPanel.setLayout(new GridLayout(0, 1)); radioPanel.add(birdButton); radioPanel.add(catButton); radioPanel.add(dogButton); radioPanel.add(rabbitButton); radioPanel.add(pigButton); setLayout(new BorderLayout()); add(radioPanel, "West"); add(picture, "Center"); setBorder(BorderFactory.createEmptyBorder(20,20,20,20)); } /** Listens to the radio buttons. */ class RadioListener implements ActionListener { public void actionPerformed(ActionEvent e) { picture.setIcon(new ImageIcon("images/" + e.getActionCommand() + ".gif")); } } public static void main(String s[]) { WindowListener l = new WindowAdapter() { public void windowClosing(WindowEvent e) {System.exit(0);} }; frame = new JFrame("RadioButtonDemo"); frame.addWindowListener(l); frame.getContentPane().add("Center", new RadioButtonDemo()); frame.pack(); frame.setVisible(true); } }