Java 学习之图形Swing编程

Java 简单登录界面

源码：

    import javax.swing.*;
    import java.awt.*;
    import java.awt.event.ActionListener;

    public class Main {

        public static void main(String[] args) {

            JFrame frame = new JFrame("登录");
            JLabel label = new JLabel();
            JLabel labelText = new JLabel("欢迎来到登录界面哈！！！");
            label.setIcon(new ImageIcon("e:\\1.jpg"));
            frame.add(label, BorderLayout.NORTH);

            Box user = Box.createHorizontalBox();
            Box pwd = Box.createHorizontalBox();
            Box btn = Box.createHorizontalBox();

            JLabel userLabel = new JLabel("用户名：");
            JLabel pwdLabel = new JLabel("密   码：");

            JTextField username = new JTextField(17);
            JTextField password = new JTextField(17);

            Font font = new Font("微软雅黑", Font.PLAIN, 20);

            userLabel.setFont(font);
            pwdLabel.setFont(font);

            username.setFont(font);
            username.setToolTipText("请输入您的用户名...");
            username.setMargin(new Insets(5, 5, 5, 5));

            password.setFont(font);
            password.setToolTipText("请输入您的密码...");
            password.setMargin(new Insets(5, 5, 5, 5));

            user.add(Box.createHorizontalStrut(10));
            user.add(userLabel);
            user.add(username);
            user.add(Box.createHorizontalStrut(10));

            pwd.add(Box.createHorizontalStrut(10));
            pwd.add(pwdLabel);
            pwd.add(password);
            pwd.add(Box.createHorizontalStrut(10));

            JButton login = new JButton("登录");
            JButton cancel = new JButton("取消");

            login.setFont(font);
            cancel.setFont(font);

            ActionListener action = e->{

                switch (e.getActionCommand()) {

                    case "登录":

                        if ("admin".equals(username.getText()) && "123456".equals(password.getText())) {

                            JOptionPane.showMessageDialog(frame, "登陆成功啦！", "恭喜", JOptionPane.INFORMATION_MESSAGE);

                        } else {

                            JOptionPane.showMessageDialog(frame, "用户名或密码错误！", "很遗憾", JOptionPane.ERROR_MESSAGE);

                        }

                        break;

                    case "取消":

                        int type = JOptionPane.showConfirmDialog(frame, "您确定取消吗？", "确认", JOptionPane.OK_CANCEL_OPTION);

                        if (type == 0) {

                            JOptionPane.showMessageDialog(frame, "很抱歉，即便您确定取消也取消不了哦！", "温馨提示", JOptionPane.INFORMATION_MESSAGE);

                        } else {

                            JOptionPane.showMessageDialog(frame, "您居然这么机智，为什么要选取消呢？", "温馨提问", JOptionPane.QUESTION_MESSAGE);

                        }

                        break;

                }

            };

            login.addActionListener(action);
            cancel.addActionListener(action);

            btn.add(Box.createHorizontalStrut(55));
            btn.add(login);
            btn.add(Box.createHorizontalStrut(10));
            btn.add(cancel);

            Box box = Box.createVerticalBox();

            labelText.setFont(font);

            box.add(labelText);
            box.add(Box.createVerticalStrut(20));
            box.add(user);
            box.add(Box.createVerticalStrut(10));
            box.add(pwd);
            box.add(Box.createVerticalStrut(20));
            box.add(btn);
            box.add(Box.createVerticalStrut(20));

            frame.add(box);
            frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            frame.setResizable(false);
            frame.pack();
            frame.setVisible(true);

        }

    }

程序用图（注意：需要放到E盘根目录下，如要放在其他目录切记要改程序中的文件路径）

运行结果：