定义窗口关闭事件

package StudyGUI;
//Panel面板和事件监听事件

import java.awt.*;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

public class StudyPanel {
    public static void main(String[] args) {
        Frame frame =  new Frame();
        Panel panel = new Panel();
        //设置布局
        frame.setLayout(null);
        //坐标
        panel.setBounds(50,50,300,300);
        panel.setBackground(Color.black);
        //颜色可以自定义颜色类
        //panel.setBackground(new Color(55,66,77));
        //将panel面板添加到窗口frame中
        frame.add (panel);
        frame.setBackground(Color.blue);
        frame.setSize(500,500);
        frame.setVisible(true);//设置窗体可见
        //定义监听事件关闭窗口
        frame.addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent e) {
                System.exit(0);
            }
        });

    }
}