具体效果图：

详细代码：

package java_gui;import java.awt.Color;
import java.awt.Container;
import java.awt.Cursor;
import java.awt.Font;
import java.awt.Image;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JCheckBox;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPasswordField;
import javax.swing.JRootPane;
import javax.swing.JTextField;public class Login extends JFrame {private static final long serialVersionUID = -6788045638380819221L;//用户名private JTextField ulName;//密码private JPasswordField ulPasswd;//小容器private JLabel j1;private JLabel j2;private JLabel j3;private JLabel j4;//小按钮private JButton b1;private JButton b2;private JButton b3;//复选框private JCheckBox c1;private JCheckBox c2;//列表框private JComboBox<String> cb1;/*** 初始化QQ登录页面* */public Login() {//设置登录窗口标题this.setTitle("QQ登录");//去掉窗口的装饰(边框)//  this.setUndecorated(true);//采用指定的窗口装饰风格this.getRootPane().setWindowDecorationStyle(JRootPane.NONE);//窗体组件初始化init();this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);//设置布局为绝对定位this.setLayout(null);this.setBounds(0, 0, 355, 265);//设置窗体的图标Image img0 = new ImageIcon("D:/logo.png").getImage();this.setIconImage(img0);//窗体大小不能改变this.setResizable(false);//居中显示this.setLocationRelativeTo(null);//窗体显示this.setVisible(true);}/*** 窗体组件初始化* */public void init() {//创建一个容器,其中的图片大小和setBounds第三、四个参数要基本一致(需要自己计算裁剪)Container container = this.getContentPane();j1 = new JLabel();//设置背景色Image img1 = new ImageIcon("D:/bgimg.png").getImage();j1.setIcon(new ImageIcon(img1));j1.setBounds(0, 0, 355, 265);//qq头像设定j2 = new JLabel();Image img2 = new ImageIcon("D:/hdimg.png").getImage();j2.setIcon(new ImageIcon(img2));j2.setBounds(40, 95, 50, 53);//用户名输入框ulName = new JTextField();ulName.setBounds(100, 100, 150, 20);//注册账号j3 = new JLabel("注册账号");j3.setBounds(260, 100, 70, 20);//密码输入框ulPasswd = new JPasswordField();ulPasswd.setBounds(100, 130, 150, 20);//找回密码j4= new JLabel("找回密码");j4.setBounds(260, 130, 70, 20);//记住密码c1 = new JCheckBox("记住密码");c1.setBounds(105, 155, 80, 15);//自动登陆c2 = new JCheckBox("自动登陆");c2.setBounds(185, 155, 80, 15);//用户登陆状态选择cb1 = new JComboBox<String>();cb1.addItem("在线");cb1.addItem("隐身");cb1.addItem("离开");cb1.setBounds(40, 150, 55, 20);//登陆按钮b1 = new JButton("登录");//设置字体和颜色和手形指针b1.setFont(new Font("宋体", Font.PLAIN, 12));b1.setForeground(Color.RED);b1.setCursor(Cursor.getPredefinedCursor(Cursor.HAND_CURSOR));b1.setBounds(280, 200, 65, 20);//给按钮添加b1.addActionListener(new ActionListener() {@Overridepublic void actionPerformed(ActionEvent e) {String cmd = e.getActionCommand();if("登录".equals(cmd)) {String username = ulName.getText();String userpassword = ulPasswd.getText();if(username.equals("tskk") && userpassword.equals("123456")) {JOptionPane.showConfirmDialog(null, "登录成功");} else {JOptionPane.showConfirmDialog(null, "登录失败");}}}});//多账号b2 = new JButton("多账号");b2.setBounds(5, 200, 75, 20);//设置b3 = new JButton("设置");b3.setBounds(100, 200, 65, 20);//所有组件用容器装载j1.add(j2);j1.add(j3);j1.add(j4);j1.add(c1);j1.add(c2);j1.add(cb1);j1.add(b1);j1.add(b2);j1.add(b3);container.add(j1);container.add(ulName);container.add(ulPasswd);}public static void main(String[] args) {new Login();}
}