代码
public class My3 extends JFrame{
public My3() {
setSize(500, 500);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setVisible(true);
setTitle("绘图实例");
add(new Mypanel());
validate();
}
public static void main(String[] args) {
// TODO Auto-generated method stub
new My3();
}
}
class Mypanel extends JPanel{
public Mypanel() {
// TODO Auto-generated constructor stub
setLayout(null);
}
@Override
public void paint(Graphics g) {
// TODO Auto-generated method stub
super.paint(g);
g.drawLine(0, 0, 250, 250);
g.drawLine(0, 250, 250, 250);
g.drawLine(0, 500, 250, 250);
g.drawLine(250, 250, 250, 500);
}
}