java菜单界面怎么做

Java中可以使用Swing或JavaFX等GUI框架来创建菜单界面。下面是一个简单的Swing菜单界面的例子：

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

public class MenuDemo extends JFrame implements ActionListener {

    private JMenuBar menuBar;
    private JMenu fileMenu, editMenu, helpMenu;
    private JMenuItem newItem, openItem, saveItem, exitItem;
    private JMenuItem cutItem, copyItem, pasteItem;
    private JMenuItem aboutItem;

    public MenuDemo() {
        setTitle("Menu Demo");
        setSize(300, 200);

        // 创建菜单栏
        menuBar = new JMenuBar();

        // 创建文件菜单
        fileMenu = new JMenu("File");
        newItem = new JMenuItem("New");
        openItem = new JMenuItem("Open");
        saveItem = new JMenuItem("Save");
        exitItem = new JMenuItem("Exit");
        fileMenu.add(newItem);
        fileMenu.add(openItem);
        fileMenu.add(saveItem);
        fileMenu.addSeparator(); // 添加分隔符
        fileMenu.add(exitItem);

        // 创建编辑菜单
        editMenu = new JMenu("Edit");
        cutItem = new JMenuItem("Cut");
        copyItem = new JMenuItem("Copy");
        pasteItem = new JMenuItem("Paste");
        editMenu.add(cutItem);
        editMenu.add(copyItem);
        editMenu.add(pasteItem);

        // 创建帮助菜单
        helpMenu = new JMenu("Help");
        aboutItem = new JMenuItem("About");
        helpMenu.add(aboutItem);

        // 将菜单添加到菜单栏
        menuBar.add(fileMenu);
        menuBar.add(editMenu);
        menuBar.add(helpMenu);

        setJMenuBar(menuBar);

        // 为菜单项添加监听器
        newItem.addActionListener(this);
        openItem.addActionListener(this);
        saveItem.addActionListener(this);
        exitItem.addActionListener(this);
        cutItem.addActionListener(this);
        copyItem.addActionListener(this);
        pasteItem.addActionListener(this);
        aboutItem.addActionListener(this);

        setVisible(true);
    }

    public void actionPerformed(ActionEvent e) {
        if (e.getSource() == newItem) {
            JOptionPane.showMessageDialog(this, "New file is created.");
        } else if (e.getSource() == openItem) {
            JOptionPane.showMessageDialog(this, "Open file dialog is shown.");
        } else if (e.getSource() == saveItem) {
            JOptionPane.showMessageDialog(this, "File is saved.");
        } else if (e.getSource() == exitItem) {
            System.exit(0);
        } else if (e.getSource() == cutItem) {
            JOptionPane.showMessageDialog(this, "Text is cut.");
        } else if (e.getSource() == copyItem) {
            JOptionPane.showMessageDialog(this, "Text is copied.");
        } else if (e.getSource() == pasteItem) {
            JOptionPane.showMessageDialog(this, "Text is pasted.");
        } else if (e.getSource() == aboutItem) {
            JOptionPane.showMessageDialog(this, "This is a menu demo.");
        }
    }

    public static void main(String[] args) {
        MenuDemo demo = new MenuDemo();
    }
}

运行程序后，会显示一个带有文件、编辑和帮助三个菜单的界面。点击菜单项会弹出对应的消息框。你可以根据自己的需求来修改菜单项的名称和功能。