1 import javax.swing.*;
2 import java.awt.event.*;
3 import java.awt.*;
4
5 public class ShowDIalog extends JFrame{
6 JButton button=new JButton("显示");
7 public ShowDIalog(){
8 setLayout(new FlowLayout());
9 add(button);
10 button.addActionListener(new ActionListener(){
11 public void actionPerformed(ActionEvent e){
12 JOptionPane.showMessageDialog(null,"Wath a fucking day!");
13 }
14 });
15 setVisible(true);
16 setSize(100,100);
17 }
18 public static void main(String[] args){
19 ShowDIalog s=new ShowDIalog();
20 }
21 }
为按钮添加个监听器
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当程序运行的时候弹出一个提示框,显示运行的极度条。
初始用户ID和密码都设置成123。密码正确后出现正在登陆的提示框,等登陆成功后,就关闭提示,退出程序。
1 import java.awt.*;
2 import javax.swing.*;
3 import java.awt.event.*;
4
5 public class Test extends JFrame implements ActionListener,Runnable {
6
7 JLabel jLabel1 = new JLabel();
8
9 JLabel jLabel2 = new JLabel();
10
11 JTextField jtUserID = new JTextField();
12
13 JLabel jLabel3 = new JLabel();
14
15 JPasswordField jpUsePwd = new JPasswordField();
16
17 JButton jbEnter = new JButton();
18
19 JButton jbExit = new JButton();
20
21 //设置登陆的用户名和密码
22
23 String userID="123";
24 String userPwd="123";
25
26 public Test() {
27 super("用户登陆界面");
28 try {
29 // 设置窗体的大小、位置、可见性
30
31 jbInit();
32 this.setVisible(true);
33 this.setSize(410, 300);
34 this.addWindowListener(new WindowAdapter() { // 清空内存
35 public void windowClosing(WindowEvent e) {
36 System.exit(0);
37 }
38 });
39 } catch (Exception exception) {
40 exception.printStackTrace();
41 }
42 }
43
44 private void jbInit() throws Exception {
45 // 初始化各控件,设置控件位置,将控件添加到面板上
46 getContentPane().setLayout(null);
47 jtUserID.setText("");
48 jtUserID.setBounds(new Rectangle(182, 50, 141, 22));
49 jLabel2.setText("用户名:");
50 jLabel2.setBounds(new Rectangle(83, 50, 78, 24));
51 jLabel3.setText("密 码:");
52 jLabel3.setBounds(new Rectangle(81, 91, 78, 24));
53 jpUsePwd.setBounds(new Rectangle(182, 92, 140, 27));
54 jbEnter.setBounds(new Rectangle(122, 197, 90, 25));
55 jbEnter.setText("登陆");
56 jbExit.setBounds(new Rectangle(217, 197, 90, 25));
57 jbExit.setText("退出");
58 this.getContentPane().add(jLabel2);
59 this.getContentPane().add(jLabel3);
60 this.getContentPane().add(jLabel1);
61 this.getContentPane().add(jtUserID);
62 this.getContentPane().add(jpUsePwd);
63 this.getContentPane().add(jbEnter);
64 this.getContentPane().add(jbExit);
65
66 jbEnter.addActionListener(this);
67 jbExit.addActionListener(this);
68
69 }
70
71
72 //多线程控制登陆信息框
73 public void run(){
74 try{
75 this.setVisible(false);
76 JOptionPane.showMessageDialog(null, "正在登陆中....");
77 Thread.sleep(3000);
78 this.dispose();
79 }catch(Exception e){
80 System.out.println(e);
81 }
82
83 }
84
85 //当点击按钮的时候触发下面的方法
86 public void actionPerformed(ActionEvent e) {
87 try{
88 String command=e.getActionCommand();
89 if (command.equals("退出")) {
90 System.exit(0);
91 } else {
92
93 // 管理员登陆功能实现
94
95 if (jtUserID.getText().equals("")
96 || new String(jpUsePwd.getPassword()).equals("")) {
97 JOptionPane.showMessageDialog(null, "请输入完整数据");
98 } else {
99 if (jtUserID.getText().equals(userID)
100 && new String(jpUsePwd.getPassword())
101 .equals(userPwd)) {
102 Thread t=new Thread(this);
103 t.start();
104
105
106
107 }
108 else {
109 JOptionPane.showMessageDialog(null, "帐号或者密码错误");
110 jtUserID.setText("");
111 jpUsePwd.setText("");
112 }
113 }
114 }
115 }catch(Exception ex){
116 System.out.println(ex);
117 }
118 }
119 public static void main(String[] args) {
120 new Test();
121 }
122 }