单击JMenuItem时如何在JLabel上显示图标？

import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.File;

public class IconDisplayExample extends JFrame {
    private JLabel iconLabel;

    public IconDisplayExample() {
        setTitle("Icon Display Example");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setPreferredSize(new Dimension(400, 300));

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

        // 创建菜单
        JMenu menu = new JMenu("操作");
        menuBar.add(menu);

        // 创建菜单项
        JMenuItem menuItem = new JMenuItem("选择图标");
        menu.add(menuItem);

        // 创建标签
        iconLabel = new JLabel();
        iconLabel.setHorizontalAlignment(SwingConstants.CENTER);
        add(iconLabel, BorderLayout.CENTER);

        // 添加事件监听器
        menuItem.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                // 打开文件选择对话框
                JFileChooser fileChooser = new JFileChooser();
                fileChooser.setFileSelectionMode(JFileChooser.FILES_ONLY);

                int result = fileChooser.showOpenDialog(IconDisplayExample.this);
                if (result == JFileChooser.APPROVE_OPTION) {
                    // 读取图标文件
                    File selectedFile = fileChooser.getSelectedFile();
                    ImageIcon icon = new ImageIcon(selectedFile.getPath());

                    // 设置标签图标
                    iconLabel.setIcon(icon);
                }
            }
        });

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

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            @Override
            public void run() {
                new IconDisplayExample();
            }
        });
    }
}