import java.awt.Color;
import java.awt.Frame;
import java.awt.Graphics;
import java.awt.Point;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.util.ArrayList;
import java.util.Iterator;
public class MyMouseAdapter {
public static void main(String[] args) {
new MyFrame5(“drawing”);
}
}
class MyFrame5 extends Frame{
ArrayList points=null;
MyFrame5(String s){
super(s);
points=new ArrayList();
setLayout(null);
setBounds(300,300,400,300);
this.setBackground(new Color(204,204,255));
setVisible(true);
this.addMouseListener(new Monitor5());
}
public void paint(Graphics g){
Iterator i=points.iterator();
while(i.hasNext()){
Point p=(Point)i.next();
g.setColor(Color.blue);
g.fillOval(p.x,p.y, 10, 10);
}
}
public void addPoint(Point p){
points.add(p);
}
}
class Monitor5 extends MouseAdapter{ //MouseAdapter实现了MouseListener接口
public void mousePressed(MouseEvent e){
MyFrame5 f=(MyFrame5)e.getSource();
f.addPoint(new Point(e.getX(),e.getY()));
f.repaint(); //让Frame强制经行重画
}
}