java随机数抽奖程序界面设计多用户输入

这里给出一个简单的 Java 随机数抽奖程序的界面设计，包含多个用户输入功能。

import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.Random;

public class LuckyDraw extends JFrame implements ActionListener {

    private JButton btnAddUser, btnDeleteUser, btnClearUsers, btnStartDraw;
    private JTextArea txtUsers, txtResult;
    private ArrayList<String> userList = new ArrayList<>();

    public LuckyDraw() {
        super("Lucky Draw");

        // add user button
        btnAddUser = new JButton("Add User");
        btnAddUser.addActionListener(this);

        // delete user button
        btnDeleteUser = new JButton("Delete User");
        btnDeleteUser.addActionListener(this);

        // clear users button
        btnClearUsers = new JButton("Clear Users");
        btnClearUsers.addActionListener(this);

        // start draw button
        btnStartDraw = new JButton("Start Draw");
        btnStartDraw.addActionListener(this);

        // user list text area
        txtUsers = new JTextArea(10, 20);
        txtUsers.setEditable(false);
        JScrollPane scrollPane1 = new JScrollPane(txtUsers);

        // result text area
        txtResult = new JTextArea(1, 20);
        txtResult.setEditable(false);
        JScrollPane scrollPane2 = new JScrollPane(txtResult);

        // layout
        JPanel btnPanel = new JPanel(new GridLayout(4, 1));
        btnPanel.add(btnAddUser);
        btnPanel.add(btnDeleteUser);
        btnPanel.add(btnClearUsers);
        btnPanel.add(btnStartDraw);

        JPanel userPanel = new JPanel(new BorderLayout());
        userPanel.add(new JLabel("Users:"), BorderLayout.NORTH);
        userPanel.add(scrollPane1, BorderLayout.CENTER);

        JPanel resultPanel = new JPanel(new BorderLayout());
        resultPanel.add(new JLabel("Result:"), BorderLayout.NORTH);
        resultPanel.add(scrollPane2, BorderLayout.CENTER);

        JPanel mainPanel = new JPanel(new BorderLayout());
        mainPanel.add(userPanel, BorderLayout.WEST);
        mainPanel.add(resultPanel, BorderLayout.EAST);
        mainPanel.add(btnPanel, BorderLayout.SOUTH);

        add(mainPanel);

        setSize(400, 400);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setVisible(true);
    }

    public static void main(String[] args) {
        new LuckyDraw();
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        if (e.getSource() == btnAddUser) {
            String name = JOptionPane.showInputDialog("Enter user name:");
            if (name != null && !name.isEmpty()) {
                userList.add(name);
                updateUsers();
            }
        } else if (e.getSource() == btnDeleteUser) {
            if (userList.size() > 0) {
                String name = JOptionPane.showInputDialog("Enter user name to delete:");
                if (name != null && !name.isEmpty()) {
                    userList.remove(name);
                    updateUsers();
                }
            }
        } else if (e.getSource() == btnClearUsers) {
            userList.clear();
            updateUsers();
        } else if (e.getSource() == btnStartDraw) {
            if (userList.size() > 0) {
                Random rand = new Random();
                int index = rand.nextInt(userList.size());
                String winner = userList.get(index);
                txtResult.setText(winner + " wins!");
            } else {
                txtResult.setText("No users!");
            }
        }
    }

    private void updateUsers() {
        txtUsers.setText("");
        for (String user : userList) {
            txtUsers.append(user + "\n");
        }
    }
}

这个程序的主要界面包含一个 "Users" 的文本区域，其中会显示当前添加的用户，以及一个 "Result" 的文本区域，用于显示抽奖结果。程序还包含四个按钮，分别是 "Add User"、"Delete User"、"Clear Users" 和 "Start Draw"，分别用于添加用户、删除用户、清空用户列表和开始抽奖。用户列表和抽奖结果都是通过 JTextArea 控件实现的，而按钮则通过 JButton 控件实现。程序还包含一个 userList 的 ArrayList，用于保存用户列表。在每次添加、删除和清空用户列表时，都需要更新文本区域的内容，这个操作是通过 updateUsers() 方法实现的。在开始抽奖时，程序会随机选择一个用户作为中奖者，并将其显示在 "Result" 文本区域中。