我的程序
import java.awt.*;
public class Wendu1 {
    public static void main(String[] args){
        Frame f=new Frame("登录窗口");
        Label lab1=new Label("ID",Label.CENTER);
        Label lab2=new Label("密码",Label.CENTER);
        Button bun1=new Button("登录");
        Button bun2=new Button("取消");
        TextField tf1=new TextField(10);
        TextField tf2=new TextField(10);
        f.add(lab1);
        f.add(lab2);
        f.add(bun1);
        f.add(bun2);
        f.add(tf1);
        f.add(tf2);
        f.setLayout(null);
        lab1.setBounds(20,50,100,30);
        lab2.setBounds(20,80,100,30);
        tf1.setBounds(120,50,100,30);
        tf2.setBounds(120,80,100,30);
        bun1.setBounds(20,110,100,30);
        bun2.setBounds(120,110,100,30);
        f.setBounds(350,200,300,150);
        f.setVisible(true);
    }
}

路过……

[ 本帖最后由 洛云 于 2011-4-17 21:31 编辑 ]

public class main {
    public static void main(String[] args){
       
        Frame f = new Frame("登录窗口");
        f.addWindowListener(new WindowAdapter(){
            @Override
            public void windowClosing(WindowEvent arg0) {
                // TODO Auto-generated method stub
                System.exit(0);
            }});
        Label lab1 = new Label("ID",Label.CENTER);
        Label lab2 = new Label("密码",Label.CENTER);
        Button bun1 = new Button("登录");
        Button bun2 = new Button("取消");
        TextField tf1 = new TextField(10);
        TextField tf2 = new TextField(10);
       
        f.add(lab1);
        f.add(lab2);
        f.add(bun1);
        f.add(bun2);
        f.add(tf1);
        f.add(tf2);
        f.setLayout(null);
       
        lab1.setBounds(20,50,100,30);
        lab2.setBounds(20,80,100,30);
        tf1.setBounds(120,50,100,30);
        tf2.setBounds(120,80,100,30);
        bun1.setBounds(20,110,100,30);
        bun2.setBounds(120,110,100,30);
        f.setBounds(350,200,300,150);
       
        f.setVisible(true);
    }
}

楼上的,是不是增加        f.addWindowListener(new WindowAdapter(){
            @Override
            public void windowClosing(WindowEvent arg0) {
                // TODO Auto-generated method stub
                System.exit(0);
            }});
这个语句就可以了

非常正确

无奈  回答的字数 必须是不能少于3

import  自己会加吧？

不行啊
WindowAdapter 下面画曲线了

import java.awt.Button;
import java.awt.Frame;
import java.awt.Label;
import java.awt.TextField;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;


public class main {
    public static void main(String[] args){
       
        Frame f = new Frame("登录窗口");
        f.addWindowListener(new WindowAdapter(){
            @Override
            public void windowClosing(WindowEvent arg0) {
                // TODO Auto-generated method stub
                System.exit(0);
            }});
        Label lab1 = new Label("ID",Label.CENTER);
        Label lab2 = new Label("密码",Label.CENTER);
        Button bun1 = new Button("登录");
        Button bun2 = new Button("取消");
        TextField tf1 = new TextField(10);
        TextField tf2 = new TextField(10);
       
        f.add(lab1);
        f.add(lab2);
        f.add(bun1);
        f.add(bun2);
        f.add(tf1);
        f.add(tf2);
        f.setLayout(null);
       
        lab1.setBounds(20,50,100,30);
        lab2.setBounds(20,80,100,30);
        tf1.setBounds(120,50,100,30);
        tf2.setBounds(120,80,100,30);
        bun1.setBounds(20,110,100,30);
        bun2.setBounds(120,110,100,30);
        f.setBounds(350,200,300,150);
       
        f.setVisible(true);
    }
}