搞定:
import javax.swing.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
public class HelloIFrame {
private static JTextArea area;
public static void main(String[] args) {
JFrame jf = new JFrame();
jf.setTitle("JAVA");
jf.setBounds(500, 200, 300, 300);
JPanel con = new JPanel(null);
area = new JTextArea();
area.setLineWrap(true);
JScrollPane jp = new JScrollPane(area);
jp.setBounds(10, 10, 280, 200);
con.add(jp);
JButton helloButton = new JButton("HELLO!");
JButton clearButton = new JButton("JAVA");
helloButton.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
area.setText("");
area.append("Hello!" + "\n");
}
});
clearButton.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
area.setText("");
area.append("JAVA!" + "\n");
}
});
helloButton.setBounds(70, 220, 75, 30);
clearButton.setBounds(150, 220, 75, 30);
con.add(helloButton);
con.add(clearButton);
jf.add(con);
jf.setResizable(false);
jf.setVisible(true);
jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}