仅当按钮被选中时才更改为JToggleButton的颜色，之后将恢复为默认颜色

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

public class ToggleButtonColorExample {
    public static void main(String[] args) {
        JFrame frame = new JFrame("Toggle Button Color Example");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setSize(300, 200);

        JToggleButton toggleButton = new JToggleButton("Toggle Button");
        toggleButton.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                if (toggleButton.isSelected()) {
                    toggleButton.setBackground(Color.RED); // 设置选中时的颜色
                } else {
                    toggleButton.setBackground(UIManager.getColor("Button.background")); // 恢复为默认颜色
                }
            }
        });

        frame.add(toggleButton);
        frame.setVisible(true);
    }
}