我这个怎么不显示我想要的东西呀？

[kofwr]

import java.applet.Applet;
import java.awt.*;

public class SimplePaint{
public static void main(String agrs[]){
Frame f=new Frame();
Canvas can=new Canvas();
f.add(can);
f.setSize(300,200);
f.setVisible(true);
}
}

class ccc extends Canvas{
public void paint(Graphics g){
g.setColor(Color.black);
g.fillRect(0,0,300,300);
g.setColor(Color.white);
g.fillOval(30,30,50,50);
}
}

[yakuu]

？？？

[马行空牛耕田]

import java.applet.Applet;
import java.awt.*;

public class SimplePaint{
public static void main(String agrs[]){
Frame f=new Frame();
Canvas can=new Canvas(); //把你的继承了Canvas的类代替这里的Canvas！！！
f.add(can);
f.setSize(300,200);
f.setVisible(true);
}
}

class ccc extends Canvas{
public void paint(Graphics g){
g.setColor(Color.black);
g.fillRect(0,0,300,300);
g.setColor(Color.white);
g.fillOval(30,30,50,50);
}
}

也就是
public class SimplePaint{
public static void main(String agrs[]){
Frame f=new Frame();
ccc can=new ccc(); //把你的继承了Canvas的类代替这里的Canvas！！！
f.add(can);
f.setSize(300,200);
f.setVisible(true);
}
}

[马行空牛耕田]

OK否?

[kofwr]

兄台，你画画，我这里创建了个实例new ccc();,可是没东西，你那里显示有嘛？？