案例

package org.lanqiao.loginui;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JPasswordField;
import javax.swing.JTextField;
public class LoginUI {
JFrame loginFrame;
JPanel loginPanel;
JTextField username;
JPasswordField password;
public LoginUI() {
loginFrame = new JFrame();
loginPanel = new JPanel();//使用空布局
username = new JTextField();
password = new JPasswordField();
}
public void init() {
loginFrame.setSize(650, 400);
loginFrame.setIconImage(new ImageIcon("image/title.gif").getImage());
loginFrame.setLocationRelativeTo(null);
loginFrame.setResizable(false);
loginFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
loginPanel = new LoginPanel("image/login1.jpg");
login