JAVA第二次作业

import javax.swing.*;
import javax.swing.event.AncestorEvent;
import javax.swing.event.AncestorListener;

import java.awt.*; //导入必要的包
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class load extends JFrame{
JTextField jTextField;//定义文本框组件
JPasswordField jPasswordField;//定义密码框组件
JLabel jLabel1,jLabel2;
JPanel jp1,jp2,jp3;
JButton jb1,jb2;//创建按钮
public load(){
jTextField = new JTextField(12);
jPasswordField = new JPasswordField(12);
jLabel1 = new JLabel("用户名");
jLabel2 = new JLabel("密 码 ");
jb1 = new JButton("确认");
jb1.addActionListener(new ActionListener(){

@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
JOptionPane.showMessageDialog(null,"正确","提示",JOptionPane.INFORMATION_MESSAGE );

}});

jb2 = new JButton("取消");
jp1 = new JPanel();
jp2 = new JPanel();
jp3 = new JPanel();

//设置布局
this.setLayout(new GridLayout(3,1));

jp1.add(jLabel1);
jp1.add(jTextField);//第一块面板添加用户名和文本框

jp2.add(jLabel2);
jp2.add(jPasswordField);//第二块面板添加密码和密码输入框

jp3.add(jb1);
jp3.add(jb2); //第三块面板添加确认和取消

// jp3.setLayout(new FlowLayout()); 　　//因为JPanel默认布局方式为FlowLayout，所以可以注销这段代码.
this.add(jp1);
this.add(jp2);
this.add(jp3); //将三块面板添加到登陆框上面
//设置显示
this.setSize(300, 150);
Dimension d = Toolkit.getDefaultToolkit().getScreenSize();
this.setLocation(d.width/2 - this.getWidth()/2, d.height/2 - this.getHeight()/2);
//this.pack();
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setVisible(true);
this.setTitle("登陆");

}
public static void main(String[] args){
new load();
}