这是什么“RecyclerView 没有 LayoutManager androidx.recyclerview.widget.RecyclerView”错误？

Question

我正在尝试从 firebase 检索数据。 但它显示“RecyclerView 没有 LayoutManager androidx.recyclerview.widget.RecyclerView”错误？ 有人可以帮我解决这个错误吗？ 错误图像

新闻适配器.java

private List<NewsModel> newsModels;

    public NewsAdapter( List<NewsModel> newsModels) {
        this.newsModels = newsModels;
    }

    @NonNull
    @Override
    public NewsViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.news,parent,false);
        return new NewsViewHolder (view);
    }

    @Override
    public void onBindViewHolder(@NonNull NewsViewHolder holder, int position) {
        NewsModel news = newsModels.get(position);

        holder.textViewName.setText(news.getName());
        holder.textViewBrand.setText(news.getBrand());
        holder.textViewDesc.setText(news.getDescription());
        holder.textViewPrice.setText("INR " + news.getPrice());
        holder.textViewQty.setText("Available Units: " + news.getQty());
    }

    @Override
    public int getItemCount() {
        return newsModels.size();
    }

    class NewsViewHolder extends RecyclerView.ViewHolder {

        TextView textViewName, textViewBrand, textViewDesc, textViewPrice, textViewQty;

        public NewsViewHolder(View itemView) {
            super(itemView);

            textViewName = itemView.findViewById(R.id.textview_name);
            textViewBrand = itemView.findViewById(R.id.textview_brand);
            textViewDesc = itemView.findViewById(R.id.textview_desc);
            textViewPrice = itemView.findViewById(R.id.textview_price);
            textViewQty = itemView.findViewById(R.id.textview_quantity);

        }


    }
}

Answer 1

如果您还没有添加回收器视图，那么您可以通过这样的 xml 代码添加它

<androidx.recyclerview.widget.RecyclerView
 android:id="@+id/contentContainer"
 android:orientation="vertical"
 app:layoutManager="androidx.recyclerview.widget.LinearLayoutManager"
 android:layout_width="match_parent"
 android:layout_height="match_parent" />

Answer 2

在您想要使用 recyclerView 的活动中：

RecyclerView recyclerView  =   findViewById(R.id.recyclerVeiw);
recyclerView.setLayoutManager(new LinearLayoutManager(this));
recyclerView.setAdapter(new YourAdapeter());