Question

java事件处理button如何单击按钮退出

import java.awt.*;
import java.awt.event.*;
public class lesson1
{
private Frame f;
private Button b;

public lesson1() {
f = new Frame("event");
b = new Button("Exit");

}

public void launchFrame()
{
b.addMouseListener(new ButtonHandler());
f.addWindowListener(new ClosingHander());
f.add(b,BorderLayout.CENTER);
f.setSize(400,300);
f.setVisible(true);

f.setVisible(true);
f.setSize(400,300);

}
public static void main(String args[])
{
lesson1 aa=new lesson1();
aa.launchFrame();
}
}

class ButtonHandler extends MouseAdapter{

{
public void mouseClicked(MouseEvent e)

{
if(e.getActionCommand().equals("Eixt"))
{
System.exit(0);

}
}
}
class ClosingHander extends WindowAdapter
{
public void windowClosing(WindowEvent e)
{
System.exit(0);
}
}

Answer 1

如果是要实现单击按钮退出，建议删掉这行代码：
if(e.getActionCommand().equals("Eixt"))

或者，将实现接口的两个类变为public的内部类，同时稍微修改下，如下

import java.awt.*;
import java.awt.event.*;

public class lesson1 {
private Frame f;
private Button b;

public lesson1() {
f = new Frame("event");
b = new Button("Exit");

}

public void launchFrame() {
b.addMouseListener(new ButtonHandler());
f.addWindowListener(new ClosingHander());
f.add(b, BorderLayout.CENTER);
f.setSize(400, 300);
f.setVisible(true);

f.setVisible(true);
f.setSize(400, 300);

}

public static void main(String args[]) {
lesson1 aa = new lesson1();
aa.launchFrame();
}

class ButtonHandler extends MouseAdapter {

public void mouseClicked(MouseEvent e)

{
if (e.getSource() == b) {
System.exit(0);

}
}
}

class ClosingHander extends WindowAdapter {
public void windowClosing(WindowEvent e) {
System.exit(0);
}
}
}

Answer 2

监听按钮，当按钮被点击时，就退出。代码如下：

jb_button.addMouseListener(new MouseAdapter() {    // 对jb_button按钮添加监听事件
    @Override
    public void mouseClicked(MouseEvent e) {    // 当鼠标点击时
        System.exit(0);        // 退出
    }
});

Answer 3

if(e.getActionCommand().equals("Eixt"))
"exit" 写错了吧...