使用public void paint(Graphics g)出现Exception in thread "main" java.lang.NullPointe
赵桑 2019-09-08 12:16:06 在重写paint()方法后,出现"Exception in thread "main" java.lang.NullPointe"的错误,代码如下:
package GameView;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class PlayGame extends JFrame{
static Graphics gp=null;
public static void main(String[] args){
PlayGame pl=new PlayGame();
pl.setSize(800,800);
pl.paint(gp);
}
public void paint(Graphics g){
super.paint(g);
setVisible(true);
g.fillRect(60, 60, 20, 20);
g.setColor(Color.BLACK);
}
}
是实例化的问题吗?调式显示g=null。要是觉得简单的话就写一下吧谢谢,我只是个java小白