这程序怎么了？为什么显示不出来

[caowy112]

public class MyButton extends JButton{
MyButton()
{
JFrame e=new JFrame();
e.setSize(200,200);
JButton d=new JButton("fdfd");
e.getContentPane().add(d);
e.setVisible(true);
}
public void paintComponent(Graphics g){
int x1[]={25,40,10,25};
int y1[]={110,140,140,110};
super.paintComponent(g);
g.fillPolygon(x1, y1, 3);
g.drawLine(10, 10, 10, 10);
}
public static void main(String []args)
{
new MyButton();
}

}

[365810247]

你把
super.paintComponent(g);
放在
g.drawLine(10, 10, 10, 10);
后面．

[guofei_gf]

那是肯定的了，你的paintComponent()是MyButton的，又不是JButton的，你在程序中也没有添加MyButton，自然不会使用paintComponent()了
这样试试吧：
public class MyButton extends JButton{
MyButton(String s)
{
super(s);
}
public void paintComponent(Graphics g){
int x1[]={25,40,10,25};
int y1[]={110,140,140,110};
super.paintComponent(g);
g.fillPolygon(x1, y1, 3);
g.drawLine(10, 10, 10, 10);
}
public static void main(String []args)
{
JFrame e=new JFrame();
e.setSize(200,200);
MyButton d=new MyButton("fdfd");
e.getContentPane().add(d);
e.setVisible(true);
}

}