mousetrack.java

介绍有关java的资料 课件 相当一本书籍 里面都是很基础的知识

import java.awt.Graphics;
import java.lang.Math;

public class MouseTrack extends java.applet.Applet {

    int mx, my;
    int onaroll;

    public void init() {
	onaroll = 0;
	resize(500, 500);
    }

    public void paint(Graphics g) {
	g.drawRect(0, 0, size().width - 1, size().height - 1);
	mx = (int)(Math.random()*1000) % (size().width - (size().width/10));
	my = (int)(Math.random()*1000) % (size().height - (size().height/10));
	g.drawRect(mx, my, (size().width/10) - 1, (size().height/10) - 1);
    }

    public boolean mouseDown(java.awt.Event evt, int x, int y) {
	requestFocus();
	if((mx < x && x < mx+size().width/10-1) && (my < y && y < my+size().height/10-1)) {
		onaroll++;
		if(onaroll > 5)
		    getAppletContext().showStatus("提示:" + onaroll + "OK!");
		else
		    getAppletContext().showStatus("提示:" + onaroll + "GOOD!");
	    }
	else {
		getAppletContext().showStatus("捕捉方框!");
		onaroll = 1;
	}
	repaint();
	return true;
    }

    public boolean mouseMove(java.awt.Event evt, int x, int y) {
	if((x % 3 == 0) && (y % 3 == 0))
	    repaint();
	return true;
    }

    public void mouseEnter() {
	repaint();
    }

    public void mouseExit() {
	onaroll = 0;
	repaint();
    }
    public void keyDown(int key) {
	requestFocus();
	onaroll = 0;
    }
}