簡単な例
import java.awt.Dimension; import java.awt.FlowLayout; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JOptionPane; public class SwingSample extends JFrame implements ActionListener { public static void main(String[] args) { SwingSample sample = new SwingSample(); sample.setBounds(0, 0, 200, 120); sample.setVisible(true); } public SwingSample() { this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); JButton button = new JButton("押せ"); button.setPreferredSize(new Dimension(120, 32)); button.addActionListener(this); this.setLayout(new FlowLayout()); this.add(button); } @Override public void actionPerformed(ActionEvent e) { JOptionPane.showMessageDialog(this, "押すな。"); } }