关于java GUI的问题
我想设计一个学生信息的简单管理系统，界面采用的是的基于一个框架的，改变框架内的内容的程序。但是当我触发触发器时界面并没有改变，我的思路是移除框架内的JPanel，再增加一个新的JPanel。但是内容并没有改变，但是当我用鼠标更改框架的大小时JPanel会更新，请问这是为什么？ 下面是部分代码。（我不想用弹出新窗口的那种方法）。
package manage;
import java.awt.FlowLayout;
import java.awt.GridLayout;
import java.awt.event.*;
import javax.swing.*;
public class Menu extends JFrame implements ActionListener{
Star star = new Star();
JButton b1 = new JButton("nzx");
public Menu(){
this.add(star);
this.setJMenuBar(star.MB1);
System.out.println("menu");
this.setBounds(10, 10, 400, 400);
this.setVisible(true);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
star.Jlogin.addActionListener(this);
star.Jbreak.addActionListener(this);
}
public void actionPerformed(ActionEvent e){
if(e.getSource() == star.Jlogin){
this.setJMenuBar(new MenuOfStudent().MOSD);
System.out.println("welcome student");
}
else if(e.getSource() == star.Jbreak){
MenuOfTeacher mot = new MenuOfTeacher();
this.setJMenuBar(mot.MOTH);
System.out.println("welcome teacher");
}
}
/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
new Menu();
}
}
*****************************************************
package manage;
import java.awt.*;
import javax.swing.*;
import java.util.*;
public class MenuOfStudent extends JPanel{
JMenuBar MOSD = new JMenuBar();
JButton Jlogin = new JButton("login");
JButton Jbreak = new JButton("break");
private JMenu MOS1 = new JMenu("11");
private JMenu MOS2 = new JMenu("22");
private JMenu MOS3 = new JMenu("33");
private JMenuItem MOS1_1 = new JMenuItem("111");
private JMenuItem MOS1_2 = new JMenuItem("112");
private JMenuItem MOS1_3 = new JMenuItem("113");
private JMenuItem MOS2_1 = new JMenuItem("221");
private JMenuItem MOS2_2 = new JMenuItem("222");
private JMenuItem MOS2_3 = new JMenuItem("223");
private JMenuItem MOS3_1 = new JMenuItem("331");
private JMenuItem MOS3_2 = new JMenuItem("332");
private JMenuItem MOS3_3 = new JMenuItem("333");
public MenuOfStudent(){
MOS1.add(MOS1_1);
MOS1.add(MOS1_2);
MOS1.add(MOS1_3);
MOS2.add(MOS2_1);
MOS2.add(MOS2_2);
MOS2.add(MOS2_3);
MOS3.add(MOS3_1);
MOS3.add(MOS3_2);
MOS3.add(MOS3_3);
MOSD.add(MOS1);
MOSD.add(MOS2);
MOSD.add(MOS3);
//this.add(new JButton("star"));
//this.add(new JButton("stop"));
}
public void paint(Graphics g){
g.drawRect(10, 10, 100, 100);
}
}
***************************************************************
package manage;
import java.awt.Graphics;
import javax.swing.*;
public class MenuOfTeacher extends JPanel{
JMenuBar MOTH = new JMenuBar();
private JMenu MOT1 = new JMenu("11");
private JMenu MOT2 = new JMenu("22");
private JMenu MOT3 = new JMenu("33");
private JMenuItem MOT1_1 = new JMenuItem("111");
private JMenuItem MOT1_2 = new JMenuItem("112");
private JMenuItem MOT1_3 = new JMenuItem("113");
private JMenuItem MOT2_1 = new JMenuItem("221");
private JMenuItem MOT2_2 = new JMenuItem("222");
private JMenuItem MOT2_3 = new JMenuItem("223");
private JMenuItem MOT3_1 = new JMenuItem("331");
private JMenuItem MOT3_2 = new JMenuItem("332");
private JMenuItem MOT3_3 = new JMenuItem("333");
public MenuOfTeacher(){
MOT1.add(MOT1_1);
MOT1.add(MOT1_2);
MOT1.add(MOT1_3);
MOT2.add(MOT2_1);
MOT2.add(MOT2_2);
MOT2.add(MOT2_3);
MOT3.add(MOT3_1);
MOT3.add(MOT3_2);
MOT3.add(MOT3_3);
MOTH.add(MOT1);
MOTH.add(MOT2);
MOTH.add(MOT3);
}
public void paint(Graphics g){
g.drawRect(100, 100, 200, 200);
}
}
***************************************************************
package manage;
import java.awt.FlowLayout;
import java.awt.event.*;
import javax.swing.*;
public class Star extends JPanel{
JRadioButton jrbt, jrbs, jrbv;
ButtonGroup group = new ButtonGroup();
JButton Jlogin = new JButton("login");
JButton Jbreak = new JButton("break");
JMenuBar MB1 = new JMenuBar();
JMenu MSI = new JMenu("information");
JMenu MSH = new JMenu("help");
JMenuItem MSH1 = new JMenuItem("About");
public Star(){
this.setLayout(new FlowLayout(FlowLayout.LEFT, 40, 40));
this.add(new JLabel("name "));
this.add(new JTextField(20));
this.add(new JLabel("password"));
this.add(new JPasswordField(20));
this.add(jrbt = new JRadioButton("teacher"));
this.add(jrbs = new JRadioButton("student"));
this.add(jrbv = new JRadioButton("visiter"));
group.add(jrbs);
group.add(jrbt);
group.add(jrbv);
this.add(Jlogin);
this.add(Jbreak);
MB1.add(MSI);
MSH.add(MSH1);
MB1.add(MSH);
}
}
