问题 问答题

本题的功能是获取鼠标在窗口中的位置。当鼠标移进窗口中,就会实时显示鼠标在窗口中的相对位置,比如显示为“鼠标的当前位置:X:Y”。(其中,X为横坐标,Y为纵坐标)
import java.awt.*;
import java.awt.event.*;
import java.util.*;
import javax.swing.*;
public class java2

public static void main(string[]args)

MouseFrame frame=new MouseFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.show();


class MouseFrame extends JFrame

public MouseFrame()

setTitle("java2");
setSize(WIDTH,HEIGHT);
MousePanel panel=new MousePanel();
Container contentPane=getContentPane();
contentPane.add(panel);

public static final int WIDTH=300;
public static final int HEIGHT=200;

class MousePanel extends JPanel

public MousePanel()

addMouseListener(new MouseHandler());
addMouseMotionListener(new MouseMorionHandler());

public void paintComponent(Graphics g)

super.paintComponent(g);
String text="鼠标指针位置:"+mousex+":"+mousey;
g.drawstring(text,10,10);

private int mousex,mousey;
private class MouseMotionHandler______

public void mouseMoved(MouseEvent event)

mousex=event.getX();
mousey=event.getY();
repaint();

public void mouseDragged(MouseEvent event)

mousex=event.getX();
mousey=event.getY();
repaint();


private class MouseHandler______

public void mousePressed(MouseEvent event)
mousex=event.getX();
mousey=event.getY();


答案

参考答案:第1处:implements MouseMotionListener
第2处:extends MouseAdapter

解析: 第1处实现了MouseMotionListener接口鼠标移动事件的监听;第2处是继承MouseAdapter这个抽象类。

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