java 底部菜单栏

以下是Java实现底部菜单栏的示例代码：

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.Font;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingConstants;

public class BottomMenuDemo extends JFrame implements ActionListener {

    private static final long serialVersionUID = 1L;

    private JPanel contentPane;
    private JPanel bottomPanel;
    private JButton btnHome;
    private JButton btnCategory;
    private JButton btnCart;
    private JButton btnProfile;

    public BottomMenuDemo() {
        setTitle("底部菜单栏示例");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setPreferredSize(new Dimension(400, 300));
        setResizable(false);

        contentPane = new JPanel(new BorderLayout());
        contentPane.setBorder(BorderFactory.createEmptyBorder(10, 10, 10, 10));

        JLabel lblTitle = new JLabel("底部菜单栏示例", SwingConstants.CENTER);
        lblTitle.setFont(new Font("宋体", Font.BOLD, 20));
        contentPane.add(lblTitle, BorderLayout.NORTH);

        JPanel centerPanel = new JPanel(new FlowLayout());
        centerPanel.add(new JLabel("这里是内容区域"));
        contentPane.add(centerPanel, BorderLayout.CENTER);

        bottomPanel = new JPanel(new GridLayout(1, 4));
        bottomPanel.setBorder(BorderFactory.createMatteBorder(1, 0, 0, 0, Color.GRAY));

        btnHome = new JButton("首页");
        btnHome.addActionListener(this);
        bottomPanel.add(btnHome);

        btnCategory = new JButton("分类");
        btnCategory.addActionListener(this);
        bottomPanel.add(btnCategory);

        btnCart = new JButton("购物车");
        btnCart.addActionListener(this);
        bottomPanel.add(btnCart);

        btnProfile = new JButton("个人中心");
        btnProfile.addActionListener(this);
        bottomPanel.add(btnProfile);

        contentPane.add(bottomPanel, BorderLayout.SOUTH);

        setContentPane(contentPane);
        pack();
        setLocationRelativeTo(null);
        setVisible(true);
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        if (e.getSource() == btnHome) {
            System.out.println("点击了首页按钮");
        } else if (e.getSource() == btnCategory) {
            System.out.println("点击了分类按钮");
        } else if (e.getSource() == btnCart) {
            System.out.println("点击了购物车按钮");
        } else if (e.getSource() == btnProfile) {
            System.out.println("点击了个人中心按钮");
        }
    }

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