//設計登陸視窗界面,當輸入賬号密碼正确時,界面如圖一所示,當輸入賬号密碼有誤時,界面如圖二所示。
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Login extends JFrame implements ActionListener{
JLabel lbzh, lbmm,lbconfirm;
//聲明帳号、密碼、确認标簽元件
JPasswordField pf;//聲明輸入密碼框元件
JTextField tfzh;
//聲明輸入帳号文本框元件
JButton btLogin;//聲明登陸按鈕元件
String zhanghao;//聲明變量賬号
String mima;//聲明變量密碼
Login(){
JFrame jf = new JFrame("登陸視窗");
jf.setVisible(true); //設定窗體可見
jf.setSize(500, 200);//設定視窗初顯大小
jf.setLocationRelativeTo(null);
JPanel jp=new JPanel();
jp.setLayout(new BorderLayout(5,10));// 構造一個邊界布局
JPanel jpTop = new JPanel();
jpTop.setLayout(new GridLayout(2,2,5,5));
JPanel jpInfo = new JPanel();
jpInfo.setLayout(new FlowLayout());
JPanel jpbtLogin = new JPanel();
jpbtLogin.setLayout(new FlowLayout());
lbzh=new JLabel("帳号",lbzh.CENTER);//建立元件并指派
lbmm=new JLabel("密碼",lbmm.CENTER);
lbconfirm=new JLabel(" ");
tfzh=new JTextField(15);
pf=new JPasswordField(15);
btLogin=new JButton("登陸");
btLogin.addActionListener(this);
jpTop.add(lbzh);// 把元件添加到面闆上
jpTop.add(tfzh);
jpTop.add(lbmm);
jpTop.add(pf);
jpInfo.add(lbconfirm);
jpbtLogin.add(btLogin);
jp.add(jpTop,BorderLayout.NORTH);
jp.add(jpInfo,BorderLayout.CENTER);
jp.add(jpbtLogin,BorderLayout.SOUTH);
jf.add(jp);
}
public void actionPerformed(ActionEvent e) {
zhanghao = tfzh.getText();
mima = pf.getText();
if(zhanghao.equals("HD") && mima.equals("123456") )
lbconfirm.setText("登入成功");
else
lbconfirm.setText("帳号或密碼有誤,請重新輸入");
}
public static void main(String[] args) {
new Login();
}
}