java的编程小问题( 帮忙找一下错哪了)

来源:百度知道 编辑:UC知道 时间:2024/09/20 14:45:13
帮忙找一下错哪了 各位!!为什么这两个程序运行总出现错误
1
import java.awt.*;
import java.awt.event.*;
public class 鼠标事件
{private Frame f;
private TextField t;
public void 鼠标事件()
{ f=new Frame(" 鼠标事件");
t=new TextField(30);}
public void launchFrame()
{Label l=new Label("点击并拖动鼠标");
f.add(l,BorderLayout.NORTH);
f.add(t,BorderLayout.EAST);
f.addMouseMotionListener(new MyMouseMotionListener());
f.setSize(500,500);
f.setVisible(true);
}

class MyMouseMotionListener extends MouseMotionAdapter
{
public void mouseDragged(MouseEvent e)
{String s="鼠标拖动的x坐标="+e.getX()+" y坐标="+e.getY();
t.setText(s);}
}

public static void main(String args[])
{鼠标事件 q=new 鼠标事件();
q.launchFrame();
}
}

2
import java.awt.*;
import java.awt.event.*;
class 鼠标事件
{private Frame f;
private TextField t;

//错误如下
import java.awt.*;
import java.awt.event.*;

public class 鼠标事件 {
private Frame f;

private TextField t;

public 鼠标事件() {
// 这里错了
// 这里应该是一个构造方法,你写成返回值为void的普通方法了
f = new Frame(" 鼠标事件");
t = new TextField(30);
}

public void launchFrame() {
Label l = new Label("点击并拖动鼠标");
f.add(l, BorderLayout.NORTH);
f.add(t, BorderLayout.EAST);
f.addMouseMotionListener(new MyMouseMotionListener());
f.setSize(500, 500);
f.setVisible(true);
}

class MyMouseMotionListener extends MouseMotionAdapter {
public void mouseDragged(MouseEvent e) {
String s = "鼠标拖动的x坐标=" + e.getX() + " y坐标=" + e.getY();
t.setText(s);
}
}

public static void main(String args[]) {
鼠标事件 q = new 鼠标事件();
q.launchFrame();
}
}

import java.awt.*;
impor