中科新闻网幼儿园人数标准:java小程序的窗口关闭问题
来源：百度文库 编辑：中科新闻网 时间：2024/05/14 03:36:03
import java.awt.*;
import java.awt.event.*;
public class TwoListen implements MouseListener,MouseMotionListener,WindowListener {
private Frame f;
private TextField tf;
public static void main(String argv[]){
TwoListen two=new TwoListen();
two.go();
}
public void go(){
f=new Frame("Two Listeners example");
f.add(new Label("click and drag the mouse"),"North");
tf=new TextField(30);
f.add(tf,"South");
f.addMouseListener( this);
f.addMouseMotionListener(this);
f.addWindowListener(this);
f.setSize(300,200);
f.setVisible(true);
}
public void mouseDragged(MouseEvent e){
String s="Mouse dragging:X="+e.getX()+"Y="+e.getY();
tf.setText(s);
}
public void mouseMoved(MouseEvent e){}
public void mouseClicked(MouseEvent e){}
public void mouseEntered(MouseEvent e){
String s="The mouse entered";
tf.setText(s);
}
public void mouseExited(MouseEvent e){
String s="The mouse has left the building";
tf.setText(s);
}
public void mousePressed(MouseEvent e){}
public void mouseReleased(MouseEvent e){}
public void windowClosing(WindowEvent e){
System.exit(1);
}
public void windowOpened(WindowEvent e){}
public void windowIconified(WindowEvent e){}
public void windowDeiconified(WindowEvent e){}
public void windowClosed(WindowEvent e){}
public void windowActivated(WindowEvent e){}
public void windowDeactivated(WindowEvent e){}
}
*************************************************************
第二个：
import java.awt.*;
import java.awt.event.*;
public class Interfaceforme extends WindowAdapter{
private Frame f;
private Button b;
public static void main(String argv[]){
Interfaceforme face=new Interfaceforme();
face.go();
}
public void go(){
f=new Frame("Two Listeners example");
f.add(new Label("click and drag the mouse"),"North");
b=new Button("hi");
f.add(b,"South");
f.setSize(300,200);
f.setVisible(true);
}
public void windowClosing(WindowEvent e){
System.exit(1);
}
public void windowClosed(WindowEvent e){}
}
************************************************************
其中第一个程序运行后，点窗口的“X”可以正常关闭，而第二个却不能，一定要用任务管理器才行。请问到底是为什么？？为什么第二个不能正常关闭呢？
第一个是可以关闭的！第二个不行，我想知道为什么，然后把第二个也变成可关闭的
第二个不能正常关闭的原因是程序显示的窗口（private Frame f）的 windowClosing 事件没有和终止程序的语句挂钩。
其实万事俱备只欠东风，因为程序里的 Interfaceforme 类是个截取 windowClosing 事件后马上终止程序的窗口事件监听器，
所以在 go( ) 方法里实例化 Frame 之后的任何地方直接加一句 f.addWindowListener( this ); 即解决了问题。
本来就不能啊
import java.awt.*;
import java.awt.event.*;
public class Interfaceforme extends WindowAdapter{
private Frame f;
private Button b;
public static void main(String args[]){
Interfaceforme face=new Interfaceforme();
face.go();
}
public void go(){
f=new Frame("Two Listeners example");
f.add(new Label("click and drag the mouse"),"North");
b=new Button("hi");
f.add(b,"South");
f.addWindowListener(new WindowAdapter(){
public void windowClosing(WindowEvent e){
System.exit(1);
}
}
);
f.setSize(300,200);
f.setVisible(true);
}
}
这样就能了，你的main方法中只有go（）方法，但是go 方法中又没有提到关闭方法，所以你的窗口关不掉了．确切的说你的frame没有注册关闭，应该给frame添加windowslistener．