Warning: file_get_contents(/data/phpspider/zhask/data//catemap/5/google-sheets/3.json): failed to open stream: No such file or directory in /data/phpspider/zhask/libs/function.php on line 167

Warning: Invalid argument supplied for foreach() in /data/phpspider/zhask/libs/tag.function.php on line 1116

Notice: Undefined index: in /data/phpspider/zhask/libs/function.php on line 180

Warning: array_chunk() expects parameter 1 to be array, null given in /data/phpspider/zhask/libs/function.php on line 181
Java BuffereImage的链接列表_Java_Animation_Linked List_Bufferedimage - Fatal编程技术网

Java BuffereImage的链接列表

Java BuffereImage的链接列表,java,animation,linked-list,bufferedimage,Java,Animation,Linked List,Bufferedimage,我正在尝试优化使用教程构建的动画类,但每当我尝试将BuffereImage添加到BuffereImage类型的LinkedList时,就会出现NullPointerException 这是我的代码: public class Animation { private int speed; private int frames; private int index = 0; private int count = 0; private LinkedList&

我正在尝试优化使用教程构建的动画类,但每当我尝试将BuffereImage添加到BuffereImage类型的LinkedList时,就会出现NullPointerException

这是我的代码:

public class Animation
{
    private int speed;
    private int frames;
    private int index = 0;
    private int count = 0;

    private LinkedList<BufferedImage> img;

    private BufferedImage currentImg;


    public Animation(int speed, BufferedImage img1, BufferedImage img2)
    {
        this.speed = speed;

        img.add(img1);
        img.add(img2);
    }
}

为什么我不能将BuffereImage添加到LinkedList?

在将图像添加到LinkedList之前,您需要创建一个新的LinkedList

现在您只是声明了一个指向它的指针,所以当您尝试添加到img时,img可能类似于null


img=新链接列表

在哪里初始化img?您应该在将元素添加到此LinkedList之前执行此操作。。。你如何调用这个构造函数?我已经尝试过这个anim=newanimation2,game.getBufferedImage0,0,game.getBufferedImage0,1