java中如何添加背景图片，是运行窗口有背景图片
java中如何添加背景图片，是运行窗口有背景图片，下面是我的一部分代码，希望大神解救。[code]import java.awt.*;import java.awt.event.*;
import javax.swing.*;
import *;
/*
*author wyfssssss
*/
public class Student {
public static void main(String[] args) {
new Student();
}
public Student(){
new MainFrame().setVisible(true);
}
public String xuesheng[][]=new String[100][7]; //存储学生基本信息
public String score[][]=new String[100][4]; //存储学生成绩
int count=0; //标记录入几个成绩信息
int cou=0; //记录有多少学生信息记录
class MainFrame extends JFrame implements ActionListener{ //主的窗口
JButton button1,button2,button3,button4,button5,button6,button7;
JPanel jp=new JPanel();
JLabel label;
public MainFrame(){
super("主界面");
jp.setLayout(null);
add(jp);
label=new JLabel("学生成绩管理系统");
label.setFont(new Font("宋体_GB2312",Font.BOLD,24));
label.setForeground(Color.blue);
label.setBounds(190,20,250,30);
jp.add(label);
setVisible(true);
setResizable(false);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setBounds(300,300,600,400);
button1=new JButton("学生信息录入");
button2=new JButton("查找or删除");
button3=new JButton("录入学生成绩");
button4=new JButton("成绩查询");
button5=new JButton("指定课程平均值");
button6=new JButton("等级人数");
button7=new JButton("排序");
button1.setBounds(100,100,170,20);
button2.setBounds(100,140,170,20);
button3.setBounds(100,180,170,20);
button4.setBounds(300,100,170,20);
button5.setBounds(300,140,170,20);
button6.setBounds(300,180,170,20);
button7.setBounds(300,220,170,20);
jp.add(button1);
jp.add(button2);
jp.add(button3);
jp.add(button4);
jp.add(button5);
jp.add(button6);
jp.add(button7);
button1.addActionListener(this);
button2.addActionListener(this);
button3.addActionListener(this);
button4.addActionListener(this);
button5.addActionListener(this);
button6.addActionListener(this);
button7.addActionListener(this);
}
public void actionPerformed(ActionEvent e){
if(e.getSource()==button1){
new AddFrame().setVisible(true);
}
else if(e.getSource()==button2){
new DeleteAndSerchFrame().setVisible(true);
}
else if(e.getSource()==button3){
new AddScoreFrame().setVisible(true);
}
else if(e.getSource()==button4){
new SerchScoreFrame().setVisible(true);
}
else if(e.getSource()==button5){
new StatScoreFrame().setVisible(true);
}
else if(e.getSource()==button6){
new DengjiFrame().setVisible(true);
}
else if(e.getSource()==button7){
new PaixuFrame().setVisible(true);
}
}
}
class AddFrame extends JFrame implements ActionListener{ //实现学生对象插入的窗口
JLabel label1 = new JLabel("添加基本信息",JLabel.CENTER);
JLabel labxuehao=new JLabel("学号：",JLabel.CENTER);
JLabel labyear=new JLabel("年龄：",JLabel.CENTER);
JLabel labName=new JLabel("姓名：",JLabel.CENTER);
JLabel labDate=new JLabel("出生日期：",JLabel.CENTER);
JLabel labclass=new JLabel("班级：",JLabel.CENTER);
JLabel labzy=new JLabel("专业：",JLabel.CENTER);
JLabel labmz=new JLabel("民族：",JLabel.CENTER);
JLabel labsex = new JLabel("性别：",JLabel.CENTER);
JLabel labmima=new JLabel("登录密码:",JLabel.CENTER);
JTextField txtName=new JTextField(20);
JTextField txtSex=new JTextField(18);
JTextField txtXueHao=new JTextField(20);
JTextField txtYear=new JTextField(20);
JTextField txtClass=new JTextField(20);
JTextField txtZY=new JTextField(20);
JTextField txtMZ=new JTextField(20);
JTextField txtMM=new JTextField(20);
JButton btnAdd=new JButton("添加");
JButton btnCancel=new JButton("返回");
JButton btnReset = new JButton("重置");
JPanel jpl=new JPanel();
File file=new File("D:\\myletter","letter.txt");
public AddFrame(){
super("添加学生信息");
this.setResizable(false);
this.setSize(550,450);
this.setVisible(true);
this.setLocation(300,300);
this.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
this.add(jpl);
jpl.setLayout(null);
btnAdd.addActionListener(this);
btnReset.addActionListener(this);
btnCancel.addActionListener(this);
jpl.setBackground(Color.cyan);
label1.setBounds(100,20,300,20);
jpl.add(label1);
labxuehao.setBounds(100,50,70,20);
jpl.add(labxuehao);
txtXueHao.setBounds(190,50,140,20);
jpl.add(txtXueHao);
labName.setBounds(100,90,70,20);
jpl.add(labName);
txtName.setBounds(190,90,140,20);
jpl.add(txtName);
labsex.setBounds(110,130,60,20);
jpl.add(labsex);
txtSex.setBounds(190,130,140,20);
jpl.add(txtSex);
labyear.setBounds(100,170,70,20);
jpl.add(labyear);
txtYear.setBounds(190,170,140,20);
jpl.add(txtYear);
labclass.setBounds(100,210,70,20);
jpl.add(labclass);
txtClass.setBounds(190,210,140,20);
jpl.add(txtClass);
labzy.setBounds(100,250,70,20);
jpl.add(labzy);
txtZY.setBounds(190,250,140,20);
jpl.add(txtZY);
labmima.setBounds(100,290,70,20);
jpl.add(labmima);
txtMM.setBounds(190,290,140,20);
jpl.add(txtMM);
btnReset.setBounds(80,380,90,20);
btnAdd.setBounds(200,380,90,20);
btnCancel.setBounds(320,380,90,20);
jpl.add(btnReset);
jpl.add(btnAdd);
jpl.add(btnCancel);
try{
file.createNewFile();
}
catch(Exception e){}
}
[code]
