Java Reference
In-Depth Information
Listing 4-6.
Configuring a Default Button
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class DefaultButton {
public static void main(String args[]) {
Runnable runner = new Runnable() {
public void run() {
JFrame frame = new JFrame("DefaultButton");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new GridLayout(2, 2, 10, 10));
JButton button1 = new JButton("Text Button");
button1.setMnemonic(KeyEvent.VK_B);
frame.add(button1);
Icon warnIcon = new ImageIcon("Warn.gif");
JButton button2 = new JButton(warnIcon);
frame.add(button2);
JButton button3 = new JButton("Warning", warnIcon);
frame.add(button3);
String htmlButton = "<html><sup>HTML</sup> <sub><em>Button</em></sub><br>" +
"<font color=\"#FF0080\"><u>Multi-line</u></font>";
JButton button4 = new JButton(htmlButton);
frame.add(button4);
JRootPane rootPane = frame.getRootPane();
rootPane.setDefaultButton(button2);
frame.setSize(300, 200);
frame.setVisible(true);
}
};
EventQueue.invokeLater(runner);
}
}
Handling JButton Events
The
JButton
component itself has no specific event-handling capabilities. They're all inherited
from
AbstractButton
. Although you can listen for change events, item events, and property
change events, the most helpful listener with the
JButton
is the
ActionListener
.
