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package javazuoye;
import javax.swing.*;

import java.awt.;
import java.awt.event.;
public class denglujiemian {

public static void main(String[] args) {
    // TODO Auto-generated method stub
    LoginDialog lo = new LoginDialog();
    lo.setVisible(true);
}

}
public class MainWindow extends JFrame{

JLabel but1;
MainWindow(){
    
    setTitle("系统登录");
    setBounds(400,200,300,180);
    setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);

// setLayout(null);

    addWindowListener(new WindowAdapter(){
        public void windowClosing(WindowEvent e){
            System.exit(0);
        }
    });
    but1 = new JLabel("登录成功！");
    this.add(but1);

}

}

public class LoginDialog extends JDialog {
JLabel name;
JLabel a2;
JComboBox a3;
JPasswordField password;
JButton shi;
JButton fou;

LoginDialog(){
    method1();
}

private void method1() {
    // TODO Auto-generated method stub
    setTitle("登录系统");
    setBounds(500,250,220,140);
    setDefaultCloseOperation(JDialog.DO_NOTHING_ON_CLOSE);
    setLayout(null);
    setModal(true);

// this.setResizable(false);

    name = new JLabel("用户名:");
    name.setBounds(20,10,50,20);
    this.add(name);
    a2 = new JLabel("密码:");
    a2.setBounds(20,32,50,20);
    this.add(a2);
    
    a3 = new JComboBox();
    a3.addItem("huakaihualuo");
    a3.addItem("hellow");
    a3.setBounds(75,10,105,20);
    this.add(a3);
    password = new JPasswordField("666666");
    password.setBounds(75,33,105,20);
    password.setEchoChar('*');
    this.add(password);
    
    shi = new JButton("登录");
    shi.setBounds(25,60,60,20);
    add(shi);
    shi.addActionListener(new ActionListener(){

        @Override
        public void actionPerformed(ActionEvent e) {
            // TODO Auto-generated method stub
            login();
        }            
    });
    fou =new JButton("退出");
    fou.setBounds(110,60,60,20);
    add(fou);
    fou.addActionListener(new ActionListener(){

        @Override
        public void actionPerformed(ActionEvent e) {
            // TODO Auto-generated method stub
            logout();
        }    
    });
    
}
void login(){
    String accout = a3.getSelectedItem().toString();
    String pwd = new String(password.getPassword());
    if(accout.equals("huakaihualuo")&&pwd.equals("666666")){
        setVisible(false);
        showMainWindow();
    }else{
        JOptionPane.showMessageDialog(this, "用户名是"+accout + ",密码是" + pwd);
    }
}
void logout(){
    int ret = JOptionPane.showConfirmDialog(this,"退出登录？","取消登录",JOptionPane.YES_NO_OPTION);
    if(ret ==JOptionPane.YES_NO_OPTION){
        dispose();
    }
}
void showMainWindow(){
    MainWindow frm = new MainWindow();
    frm.setVisible(true);
}

}