RecycleView代码不更新！更新代码应该怎么写呢，有没有人教一下
网络数据取到了，Recycleview 没显示出来数据

public class FoodFragment extends Fragment {
    public RecyclerView mFoodRecyclerView;//定义RecyclerView
    //定义以goodsentity实体类为对象的数据集合
    private ArrayList<FoodEntity> goodsEntityList = new ArrayList<FoodEntity>();
    //自定义recyclerveiw的适配器
    private FoodRecycleAdapter mRecyclerAdapter;
    private JSONArray array;



    public  FoodFragment() {
    }

    private static ChangeFoodFragment changeFoodFragment;

    public static FoodFragment newInstance(ChangeFoodFragment foodFragment){
        changeFoodFragment = foodFragment;
        Bundle args = new Bundle();

        FoodFragment fragment = new FoodFragment();
        fragment.setArguments(args);
        return fragment;
    }
    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container,
                             @Nullable Bundle savedInstanceState) {
        View  view = inflater.inflate(R.layout.recyclerview_food, container, false);
        //对recycleview进行配置

        return view;
    }
    @Override
    public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);
        initData();
        initRecyclerView(view);





    }
    private void initData() {
        new Thread(){
            public void run()
            {
                String url = DocUtil.food_list;
                OkHttpClient okHttpClient = new OkHttpClient();

                String token= CacheUtils.getString(getActivity(), "token", "");
                RequestBody body = new FormBody.Builder()
                        .add("token",token)
                        .build();

                Request request = new Request.Builder()
                        .url(url)
                        .post(body)
                        .build();

                Call call = okHttpClient.newCall(request);
                try {
                    Response response = call.execute();
                    //System.out.println(response.body().string());
                    try {
                        final String string=response.body().string();
                        final JSONObject object=new JSONObject(string);

                        array=object.getJSONArray("list");
                        System.out.println(array);
                        if(array.length()>0) {

                            try {
                                FoodEntity foodEntity =new FoodEntity();
                                for(int i=0;i<array.length();i++){
                                    JSONObject object1=array.getJSONObject(i);
                                    foodEntity.setFoodtitle(object1.getString("foodtitle"));
                                    foodEntity.setFoodcontent(object1.getString("foodcontent"));
                                    foodEntity.setFoodcontentimg(object1.getString("foodcontentimg"));
                                    System.out.println(object1.getString("foodtitle"));
                                    System.out.println(object1.getString("foodcontent"));
                                    System.out.println(object1.getString("foodcontentimg"));



                                }



                            } catch (Exception e) {
                                e.printStackTrace();
                            }
                        }else {
                            Toast.makeText(getActivity(), "无数据", Toast.LENGTH_SHORT).show();
                        }
                    } catch (JSONException e) {
                        e.printStackTrace();
                    }
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }.start();




//        for (int i=0;i<10;i++){
//            FoodEntity foodEntity =new FoodEntity();
//            foodEntity.setName("模拟数据FOOD"+i);
//            foodEntity.setContent("100"+i);
//            goodsEntityList.add(foodEntity);
//        }
    }
    private void initRecyclerView(View view) {
        //获取RecyclerView
        mFoodRecyclerView=view.findViewById(R.id.food_recyclerView);
        //创建adapter
        mRecyclerAdapter = new FoodRecycleAdapter(getActivity(), goodsEntityList);
        //给RecyclerView设置adapter
        mFoodRecyclerView.setAdapter( mRecyclerAdapter );
        //设置layoutManager,可以设置显示效果，是线性布局、grid布局，还是瀑布流布局
        //参数是：上下文、列表方向（横向还是纵向）、是否倒叙
        mFoodRecyclerView.setLayoutManager(new LinearLayoutManager(getActivity(), LinearLayoutManager.VERTICAL, false));
        //设置item的分割线
        mFoodRecyclerView.addItemDecoration(new DividerItemDecoration(getActivity(),DividerItemDecoration.VERTICAL));


        //RecyclerView中没有item的监听事件，需要自己在适配器中写一个监听事件的接口。参数根据自定义
        mRecyclerAdapter.setOnItemClickListener(new FoodRecycleAdapter.OnItemClickListener() {
            @Override
            public void OnItemClick(View view, FoodEntity data) {
                Toast.makeText(getActivity(),"我是item",Toast.LENGTH_SHORT).show();
                changeToAnotherFragment();
            }
        });

    }
    @SuppressLint("ResourceType")
    private void changeToAnotherFragment() {
        changeFoodFragment.changeFoodFragment();
    }
}

public class FoodRecycleAdapter extends RecyclerView.Adapter<FoodRecycleAdapter.myViewHodler>{

    private Context context;
    private ArrayList<FoodEntity> goodsEntityList;
    private ImageLoaderConfiguration configuration;
    public DisplayImageOptions imageOptions;
    private FoodRecycleAdapter adapter;


    //创建构造函数
    public FoodRecycleAdapter(Context context, ArrayList<FoodEntity> goodsEntityList) {
        //将传递过来的数据，赋值给本地变量
        this.context = context;//上下文
        this.goodsEntityList = goodsEntityList;//实体类数据ArrayList
    }

    /**
     * 创建viewhodler，相当于listview中getview中的创建view和viewhodler
     *
     * @param parent
     * @param viewType
     * @return
     */
    @Override
    public myViewHodler onCreateViewHolder(ViewGroup parent, int viewType) {
        //创建自定义布局

        View itemView = View.inflate(context, R.layout.food_item, null);

        return new myViewHodler(itemView);
    }

    /**
     * 绑定数据，数据与view绑定
     *
     * @param holder
     * @param position
     */
    @Override
    public void onBindViewHolder(myViewHodler holder, int position) {
             //根据点击位置绑定数据
        FoodEntity data = goodsEntityList.get(position);
//        holder.mItemGoodsImg;
        configuration = ImageLoaderConfiguration.createDefault(context);
        ImageLoader.getInstance().init(configuration);
        imageOptions = DisplayImageOptions.createSimple();
        holder.mItemGoodsName.setText(data.foodtitle);//获取实体类中的name字段并设置
        holder.mItemContent.setText(data.foodcontent);//获取实体类中的price字段并设置
        adapter=new FoodRecycleAdapter(context, goodsEntityList);

        adapter.notifyItemRangeInserted(position,getItemCount());

//        ImageLoader.getInstance().displayImage(DocUtil.base_url+
//                        data.foodcontentimg, mItemGoodsImg,
//                imageOptions);

    }

    /**
     * 得到总条数
     *
     * @return
     */
    @Override
    public int getItemCount() {
        return goodsEntityList.size();
    }

    //自定义viewhodler
    class myViewHodler extends RecyclerView.ViewHolder {
        private ImageView mItemGoodsImg;
        private TextView mItemGoodsName;
        private TextView mItemContent;

        public myViewHodler(View itemView) {
            super(itemView);
            mItemGoodsImg = itemView.findViewById(R.id.food_img);
            mItemGoodsName =  itemView.findViewById(R.id.food_title);
            mItemContent =  itemView.findViewById(R.id.tx_content);

            //点击事件放在adapter中使用，也可以写个接口在activity中调用
            //方法一：在adapter中设置点击事件
            itemView.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    //可以选择直接在本位置直接写业务处理
                    //Toast.makeText(context,"点击了xxx",Toast.LENGTH_SHORT).show();
                    //此处回传点击监听事件

                    if(onItemClickListener!=null){
                        onItemClickListener.OnItemClick(v, goodsEntityList.get(getLayoutPosition()));
                    }
                }
            });

        }
    }

    /**
     * 设置item的监听事件的接口
     */
    public interface OnItemClickListener {
        /**
         * 接口中的点击每一项的实现方法，参数自己定义
         *
         * @param view 点击的item的视图
         * @param data 点击的item的数据
         */
        public void OnItemClick(View view, FoodEntity data);
    }

    //需要外部访问，所以需要设置set方法，方便调用
    private FoodRecycleAdapter.OnItemClickListener onItemClickListener;

    public void setOnItemClickListener(FoodRecycleAdapter.OnItemClickListener onItemClickListener) {
        this.onItemClickListener = onItemClickListener;
    }
}

怎么从一个类访问另一类的arraylist

yg1a20

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