62,634
社区成员




import javax.swing.*;
import java.awt.*;
public class Demo9_1 extends JFrame {
MyPanel mp = null;
public static void main(String[] args) {
Demo9_1 demo9_1 = new Demo9_1();
}
public Demo9_1() {
mp = new MyPanel();
this.add(mp);
// =========================================
this.setSize(400, 300);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setVisible(true);
// =========================================
}
}
class MyPanel extends JPanel {
public void paint(Graphics g) {
super.paint(g);
System.out.println("paint() is called !");
g.setColor(Color.red);
g.fillRect(70, 10, 40, 60);
g.setColor(Color.blue);
g.fillRect(70, 90, 40, 60);
}
}