Java 小问题，等代求教

[Janyue]

//在面板上显示一条信息
import javax.swing.*;
import java.awt.*;
//import java.awt.event.*;
import java.awt.geom.*;



public class SimpleFrameTest
{
public static void main(String[] args)
{
SimpleFrame frame = new SimpleFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.show();
}
}

//框架类
class SimpleFrame extends JFrame
{
public SimpleFrame()
{


setTitle("This is a Title");
setSize(WIDTH,HEIGHT);

//加入一个面板到框架

HelloPanel panel = new HelloPanel ();
Container contentPane = getContentPane();

contentPane.add(panel);

}
public static final int WIDTH = 400;
public static final int HEIGHT = 400;
}

[huaiyusong]

写清楚点啊

[UnAgain]

呵呵，这是道填空题

import javax.swing.*;
import java.awt.*;
//import java.awt.event.*;
import java.awt.geom.*;



public class SimpleFrameTest
{
public static void main(String[] args)
{
SimpleFrame frame = new SimpleFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
}

//框架类
class SimpleFrame extends JFrame
{
public SimpleFrame() {

setTitle("This is a Title");
setSize(WIDTH,HEIGHT);

//加入一个面板到框架
HelloPanel panel =
new HelloPanel("Hello this is message", 100, 100);
Container contentPane = getContentPane();

contentPane.add(panel);

}

class HelloPanel extends JPanel{
String msg = null;
int MESSAGE_X, MESSAGE_Y;

HelloPanel(String msg, int x, int y){
super();
this.msg = msg;
MESSAGE_X = x;
MESSAGE_Y = y;
}
public void paint(Graphics g){
g.drawString(msg, MESSAGE_X, MESSAGE_Y);
}
}

public static final int WIDTH = 400;
public static final int HEIGHT = 400;
}

[捏造的信仰]

程序看到了，问题楼主忘了写了？

[Janyue]

就这些，我就是要让g.drawString("Hello this is message",MESSAGE_X,MESSAGE_Y);显示出来，可是出来的窗口空白的 why?

[huangdeji]

不会，帮你鼎一下

[hsuyuan]

HelloPanel 是什么类型的 好像不对吧

[Camelh]

把HelloPanel类的代码贴出来

[SanFire]

怎么不见你的画图函数啊？画图函数没有调用怎么会显示呢？进入调用画图函数代码。

[tomison]

请楼主把问题写详细点，HelloPanel类的代码也没给出来，又没提及画图的函数