javaGUI–窗口事件监听

窗口事件监听 常用的就是窗口激活和窗口关闭,两个事件的监听.

写法1:(推荐)匿名内部类

package cn.usts.edu.lesson03;

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

public class TestWindowsListener {
    public static void main(String[] args) {
        new WindowsListenerFrame();
    }
}


class WindowsListenerFrame extends Frame{
    public WindowsListenerFrame() {
        setBounds(200,200,400,200);
        setVisible(true);
        // 匿名内部类
        this.addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent e) {
                setVisible(false);// 隐藏窗口
            }
        });

        this.addWindowListener(new WindowAdapter() {
            @Override
            public void windowActivated(WindowEvent e) {
                WindowsListenerFrame windowsListenerFrame = (WindowsListenerFrame) e.getSource();
                windowsListenerFrame.setTitle("被激活了");
            }
        });

        this.addWindowListener(new WindowAdapter() {
            @Override
            public void windowDeactivated(WindowEvent e) {
                WindowsListenerFrame source = (WindowsListenerFrame) e.getSource();
                source.setTitle("没有被激活");
            }
        });
    }

}

写法2:内部类

package cn.usts.edu.lesson03;

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

public class TestWindowsListener {
    public static void main(String[] args) {
        new WindowsListenerFrame();
    }
}


class WindowsListenerFrame extends Frame{
    public WindowsListenerFrame() {
        setBounds(200,200,200,200);
        setVisible(true);
        addWindowListener(new MyWindowsListenerFrame());
    }
    
    // 内部类
    class MyWindowsListenerFrame extends WindowAdapter{
        @Override
        public void windowClosing(WindowEvent e) {
            setVisible(false);// 点击关闭窗口就是隐藏了,不是结束程序,程序还在后台运行
            //System.exit(0);  // 正常的点击x结束程序的语句
        }
    }
}