关于Paint重画问题。。

[qqchilaidefeng]

这个是，我用图形的颜色和背景的颜色相同的方法，但我觉得这种方法使代码太长了。有没有直接的重画方法？
也就是在画第二个图形的时候，先把第一个图形给覆盖掉

import java.awt.*;
import java.awt.event.*;
import java.applet.*;
public class huantu extends Applet implements ActionListener{
    Graphics g;
    Panel panel=new Panel();
    Button button1=new Button("画直线");
    Button button2=new Button("画矩形");
    Button button3=new Button("画多边形");
    Button button4=new Button("画圆");
    Button button5=new Button("画扇形");
   public void init(){
        add(button1);
        add(button2);
        add(button3);
        add(button4);
        add(button5);
        button1.addActionListener(this);
        button2.addActionListener(this);
        button3.addActionListener(this);
        button4.addActionListener(this);
        button5.addActionListener(this);
    }
       public void actionPerformed(ActionEvent e) {
         g = getGraphics();
          if(e.getSource()==button1)
          paint(g,1);
       else if(e.getSource()==button2)
          paint(g,2);
       else if(e.getSource()==button3)
           paint(g,3);
       else if(e.getSource()==button4)
           paint(g,4);
       else if(e.getSource()==button5)
           paint(g,5);
    }

    public void  paint(Graphics g,int i){
        if(i==1){
             g.setColor(Color.white);                 //覆盖矩形
             g.drawRect(50, 50, 50, 100);
             g.fillRect(130, 50, 50, 100);
             g.fillRect(200, 50, 100, 50);
             int x1[]={20,60,100,130,80};               //  覆盖多边形
             int y1[]={60,80,150,40,60};
             int x2[]={220,260,300,330,280};
             int y2[]={60,80,150,40,60};
             g.drawPolygon(x1, y1, 5);
             g.fillPolygon(x2, y2, 5);
             g.drawOval(60, 60, 60, 60);            //覆盖圆
             g.fillOval(180, 60, 60, 60);
             g.fillArc(60, 80, 80, 80, 30, 70);          // 覆盖扇形
             g.fillArc(200, 80, 80, 80, 60, 140);
             g.setColor(Color.red);                   //画直线
             g.drawLine(30, 60, 80, 60);
             g.drawLine(100, 60, 150, 100);
             g.drawLine(160, 100, 270, 60);     
        }
        else if(i==2){
            g.setColor(Color.white);                     //覆盖直线
            g.drawLine(30, 60, 80, 60);
            g.drawLine(100, 60, 150, 100);
            g.drawLine(160, 100, 270, 60);
            int x1[]={20,60,100,130,80};                   //覆盖多边形
             int y1[]={60,80,150,40,60};
             int x2[]={220,260,300,330,280};
             int y2[]={60,80,150,40,60};
             g.drawPolygon(x1, y1, 5);
             g.fillPolygon(x2, y2, 5);
             g.drawOval(60, 60, 60, 60);                  // 覆盖圆
             g.fillOval(180, 60, 60, 60);
             g.fillArc(60, 80, 80, 80, 30, 70);           //覆盖扇形
             g.fillArc(200, 80, 80, 80, 60, 140);
             g.setColor(Color.green);                  //画矩形
             g.drawRect(50, 50, 50, 100);
             g.fillRect(130, 50, 50, 100);
             g.fillRect(200, 50, 100, 50);
        }
        else if(i==3){
             g.setColor(Color.white);                //覆盖直线
             g.drawLine(30, 60, 80, 60);
             g.drawLine(100, 60, 150, 100);
             g.drawLine(160, 100, 270, 60);
             g.drawRect(50, 50, 50, 100);                     //覆盖矩形
             g.fillRect(130, 50, 50, 100);
             g.fillRect(200, 50, 100, 50);
             g.drawOval(60, 60, 60, 60);                //覆盖圆
             g.fillOval(180, 60, 60, 60);
             g.fillArc(60, 80, 80, 80, 30, 70);            // 覆盖扇形
             g.fillArc(200, 80, 80, 80, 60, 140);
             g.setColor(Color.blue);             //画多边形
             int x1[]={20,60,100,130,80};
             int y1[]={60,80,150,40,60};
             int x2[]={220,260,300,330,280};
             int y2[]={60,80,150,40,60};
             g.drawPolygon(x1, y1, 5);
             g.fillPolygon(x2, y2, 5);
        }
        else if(i==4){
            g.setColor(Color.white);                //覆盖直线
             g.drawLine(30, 60, 80, 60);
             g.drawLine(100, 60, 150, 100);
             g.drawLine(160, 100, 270, 60);
             g.drawRect(50, 50, 50, 100);        //覆盖矩形
             g.fillRect(130, 50, 50, 100);
             g.fillRect(200, 50, 100, 50);
              int x1[]={20,60,100,130,80};       //覆盖多边形
             int y1[]={60,80,150,40,60};
             int x2[]={220,260,300,330,280};
             int y2[]={60,80,150,40,60};
             g.drawPolygon(x1, y1, 5);
             g.fillPolygon(x2, y2, 5);
             g.fillArc(60, 80, 80, 80, 30, 70);                  //覆盖扇形
             g.fillArc(200, 80, 80, 80, 60, 140);
             g.setColor(Color.pink);                  //画圆
             g.drawOval(60, 60, 60, 60);
             g.fillOval(180, 60, 60, 60);
        }
        else if(i==5){
            g.setColor(Color.white);                //覆盖直线
             g.drawLine(30, 60, 80, 60);
             g.drawLine(100, 60, 150, 100);
             g.drawLine(160, 100, 270, 60);
             g.drawRect(50, 50, 50, 100);        //覆盖矩形
             g.fillRect(130, 50, 50, 100);
             g.fillRect(200, 50, 100, 50);
             int x1[]={20,60,100,130,80};       //覆盖多边形
             int y1[]={60,80,150,40,60};
             int x2[]={220,260,300,330,280};
             int y2[]={60,80,150,40,60};
             g.drawPolygon(x1, y1, 5);
             g.fillPolygon(x2, y2, 5);
             g.drawOval(60, 60, 60, 60);            //覆盖圆
             g.fillOval(180, 60, 60, 60);
             g.setColor(Color.orange);            //画扇形
             g.fillArc(60, 80, 80, 80, 30, 70);
             g.fillArc(200, 80, 80, 80, 60, 140);
        }
   }
}

[qqchilaidefeng]

谢了啊。。

[magong]

不需要覆盖，在每次画图之前清除就行了，如下

g.clearRect(0, 0, this.getWidth(), this.getHeight() );