JAVA重写paint画图

 

package demo;
import java.awt.*;
import java.awt.event.*;
public class FrameTest {
 public static void main(String[] args) {
  new MyFrame();
 } 
}

class MyFrame extends Frame {
 MyFrame(){
  this.setLocation(500, 200);
  this.setSize(400, 300);
  this.setLayout(new FlowLayout());
  this.setVisible(true);
 }

 public void paint(Graphics g){
  Color c = g.getColor();
  g.setColor(Color.red);
  g.fillOval(100, 100, 80, 80);
  g.drawLine(300, 280, 50, 280);
  g.drawLine(250, 10, 250, 250);
  g.setColor(c);
 }
}