Java-GUI-监听

按钮监听

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

public class TestActionEvent {
    public static void main(String[] args) {
        //按下按钮触发一些事件。
        Frame frame = new Frame();
        Button button = new Button("button");
        button.setBounds(11,11,11,11);

        //因为addActionListener()需要一个ActionListener所以我们要构造一个ActionListener。
        MyActionListener myActionListener = new MyActionListener();
        button.addActionListener(myActionListener);

        WindowsClose(frame);//窗口关闭事件

        frame.add(button);
        frame.setVisible(true);
        frame.setBounds(222,222,222,222);
    }

    //窗口关闭事件
    private static void WindowsClose(Frame frame){
        frame.addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent e) {
                System.exit(0);
            }
        });

    }
}

//ActionListener事件监听
class MyActionListener implements ActionListener{

    @Override
    public void actionPerformed(ActionEvent e) {
        System.out.println("aaa");
    }
}

按钮监听事件共用

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

public class TestActionTwo extends TestActionEvent {
    public static void main(String[] args) {
        //实现两个按钮实现同一个监听
        //开始    停止
        Frame frame = new Frame("start-stop");
        Button button1 = new Button("start");
        Button button2 = new Button("stop");

        //可以显示的定义除法会返回的命令，否则返回默认的Label
        button2.setActionCommand("button2-stop");

        MyMonitor myMonitor = new MyMonitor();


        button1.addActionListener(myMonitor);
        button2.addActionListener(myMonitor);

        frame.add(button1,BorderLayout.NORTH);
        frame.add(button2,BorderLayout.SOUTH);

        frame.setBounds(300,300,300,300);
        frame.setVisible(true);
    }
}
class MyMonitor implements ActionListener{

    @Override
    public void actionPerformed(ActionEvent e) {
        if (e.getActionCommand().equals("start"))
            System.out.println("点击了开始："+e.getActionCommand());
        else System.out.println("点击了停止："+e.getActionCommand());
    }

文本框 TestField 监听事件

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

public class TestText01 {
    public static void main(String[] args) {
        //启动！
        new MyFrame();
    }
}
class MyFrame extends Frame{
    public MyFrame(){
        TextField textField = new TextField();
        add(textField);

        //监听这个文本框输入的文字
        MyActionListener2 myActionListener = new MyActionListener2();
        //按下enter就会触发这个输入框的事件
        textField.addActionListener(myActionListener);

        //设置密码文本
        textField.setEchoChar('*');

        pack();
        setVisible(true);
    }
}
class MyActionListener2 implements ActionListener{
    @Override
    public void actionPerformed(ActionEvent e) {
        TextField source =(TextField) e.getSource();//获得一些资源、返回的一个对象
        System.out.println(source.getText());//获得输入框的文本。
        source.setText("");
    }
}