一个跟随鼠标的问题
小弟初学JAVA,在下面这个例子里,当鼠标移动时,一个十字指针(画的)可以一直跟着鼠标,但只要鼠标移动过的地方一直会有移动时画下来的十字架,请问有什么方法可以清除(即窗体里只有跟着鼠标走的那个)
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class mouseMoveDemo extends JFrame{
myjp pMain=new myjp();
mouseMoveDemo(){
super("跟随鼠标移动的十字架");
Container myPan=getContentPane();
myPan.add(pMain);
this.setBounds(300,300,300,300);
this.show();
this.setDefaultCloseOperation(this.EXIT_ON_CLOSE);
this.repaint();
}
public static void main(String[] args){
mouseMoveDemo frmMain=new mouseMoveDemo();
}
}
class myjp extends JPanel{
myjp(){
this.addMouseMotionListener(new myAdapter());
}
public void paintComponent(Graphics g){
g.fillRect(50,50,100,100);
}
private class myAdapter extends MouseMotionAdapter{
public void mouseMoved(MouseEvent e){
int x=e.getX();
int y=e.getY();
Graphics g=getGraphics();
g.setXORMode(Color.green);
g.drawLine(x-10,y,x+10,y);
g.drawLine(x,y-10,x,y+10);
}
}
}