为何运行后窗体空白没有显示字符，解决立即给分！

[zhongshupeng]

import java.awt.*;
import javax.swing.*;
public class HelloPanel extends JFrame {


public static void main(String[] args){
MyFrame f=new MyFrame();
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.show();

}

}

class MyFrame extends JFrame{
MyFrame(){

setSize(900,600);
setTitle("Title");
MyPanel m=new MyPanel();
Container j=getContentPane();
j.add(m);

}
}
class MyPanel extends JPanel{
public void paintConponent(Graphics g){
super.paintComponent(g);
g.drawString("Hello Panel", 100, 100);

}
}

[qybao]

你的panel没有设置大小啊？也就是说你的panel是0size，看不见的
这样试试看
class MyFrame extends JFrame{
MyFrame(){
setSize(900,600);
setTitle("Title");
MyPanel m=new MyPanel();
m.setSize(500, 500);
Container j=getContentPane();
j.setLayout(new BorderLayout());
j.add(m, BorderLayout.CENTER);
}
}

[chill_ming]

MyPanel 應該重寫paint方法
詳情如下：
class MyPanel extends JPanel {
public void paint(Graphics g) {
super.paintComponent(g);
g.drawString("Hello Panel", 100, 100);
}
}

[xp7024b]

你的MyPanel 有问题根本没有覆盖掉父类的paintConponent

class MyPanel extends JPanel {

@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawString("Hello Panel", 100, 100);
}

}