java applet 画个矩形 有问题但依然能画 奇！

来源：百度知道 编辑：UC知道 时间：2024/06/14 08:31:14
import java.awt.Point;
import java.awt.Graphics;
import java.applet.Applet;
import java.awt.event.MouseEvent;
import java.awt.event.MouseAdapter;
public class DrawRect extends Applet
{
Point p1,p2;
int width,height;
public void init()
{

}
public void start()
{
addMouseListener(new Mouse());
//addMouseMotionListener(new MouseAdapter());
}
public void paint(Graphics g)
{
g.drawRect(p1.x,p1.y,width,height);
}
public class Mouse extends MouseAdapter
{
public void mousePressed(MouseEvent e)
{
p1=new Point(e.getX(),e.getY());
}
public void mouseReleased(MouseEvent e)
{
p2=new Point(e.getX(),e.getY());
width=Math.abs(p1.x-p2.x);
height=Math.abs(p1.y-p2.y);
repaint();
}
public void mouseDragged(MouseEvent e)
{

}
}
}
//<applet code=DrawR

//你未初始化了~~

import java.awt.Point;
import java.awt.Graphics;
import java.applet.Applet;
import java.awt.event.MouseEvent;
import java.awt.event.MouseAdapter;

public class DrawRec extends Applet {
private static final long serialVersionUID = -550227402407688879L;

Point p1 = new Point();
Point p2 = new Point();

int width, height;

Graphics g = this.getGraphics();

public void init() {

}

public void start() {
addMouseListener(new Mouse());
}

public void paint(Graphics g) {
g.drawRect(p1.x, p1.y, width, height);
}

public class Mouse extends MouseAdapter {
public void mousePressed(MouseEvent e) {
p1.setLocation(e.getX(), e.getY());
}

public void mouseReleased(MouseEvent e) {
p2.setLocation(e.getX(), e.getY());
width = Math.abs(p1.x - p2.x);
height = Math.abs(