更改actionlistener中的变量数据

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

public class ActionListenerExample {
    // 定义一个成员变量
    private int counter = 0;

    public void createAndShowGUI() {
        JFrame frame = new JFrame("ActionListener Example");
        JButton button = new JButton("Click Me");

        // 添加ActionListener
        button.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                // 在ActionListener中更改成员变量的值
                counter++;
                System.out.println("Button clicked! Counter: " + counter);
            }
        });

        frame.add(button);
        frame.setSize(300, 200);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);
    }

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

button.addActionListener(e -> {
    counter++;
    System.out.println("Button clicked! Counter: " + counter);
});