import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class HelloWorld extends JApplet implements ActionListener {
private JButton button1;
private GridBagLayout gl;
private GridBagConstraints gc;
public void init() {
gl = new GridBagLayout();
gc = new GridBagConstraints();
this.setLayout(gl);
this.addButton();
}
public void actionPerformed(ActionEvent e) {
if (e.getSource() == button1) {
JOptionPane.showMessageDialog(null, "Hello, World");
}
}
public void addButton() {
button1 = new JButton("Click!");
button1.addActionListener(this);
gc.gridx = 0;
gc.gridy = 0;
gc.gridwidth = 0;
gc.gridheight = 1;
gc.weightx = 1;
gc.weighty = 1;
gl.setConstraints(button1, gc);
this.add(button1);
}
}