解决方法是在底部设置初始化的空列表和适配器，并在获取结果时调用notifyDataSetChanged。

    LinearLayoutManager linearLayoutManager = new LinearLayoutManager(getContext());
    recyclerviewItems.setLayoutManager(linearLayoutManager);
    someAdapter = new SomeAdapter(getContext(),feedList);
    recyclerviewItems.setAdapter(someAdapter);

对于那些在片段中使用RecyclerView并从其他视图中扩展它的人:当扩展整个片段视图时，确保将RecyclerView绑定到它的根视图。

我为适配器正确地连接和做了所有事情，但我从未进行绑定。 @Prateek Agarwal的回答已经为我提供了一切，但这里有更详细的说明。

科特林

    override fun onCreateView(inflater: LayoutInflater?, container: ViewGroup?, savedInstanceState: Bundle?): View? {

    val rootView =  inflater?.inflate(R.layout.fragment_layout, container, false)
    recyclerView = rootView?.findViewById(R.id.recycler_view_id)
    // rest of my stuff
    recyclerView?.setHasFixedSize(true)
    recyclerView?.layoutManager = viewManager
    recyclerView?.adapter = viewAdapter
    // return the root view
    return rootView
}

Java

  @Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

    View rootView= inflater.inflate(R.layout.fragment_layout,container,false);
    recyclerview= rootView.findViewById(R.id.recycler_view_id);
    return rootView;
}

在您的RecyclerView适配器类中，例如MyRecyclerViewAdapter，使用以下参数创建一个构造函数。

MyRecyclerViewAdapter(Context context, List<String> data) {
    this.mInflater = LayoutInflater.from(context); // <-- This is the line most people include me miss
    this.mData = data;
}

mData是传递给适配器的数据。如果没有要传递的数据，则该选项是可选的。 mInflater是你创建的LayoutInflater对象，你在适配器的OnCreateViewHolder函数中使用。

在此之后，您可以将适配器附加到MainActivity或主/UI线程上您想要的任何地方

MyRecyclerViewAdapter recyclerAdapter;
OurDataStuff mData;

    ....
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        //Like this:

        RecyclerView recyclerView = findViewById(R.id.recyclerView);
        recyclerView.setLayoutManager(new LinearLayoutManager(this));
        recyclerAdapter = new RecyclerAdapter(this, mData); //this, is the context. mData is the data you want to pass if you have any
        recyclerView.setAdapter(recyclerAdapter);
    }
   ....

你能确保你在延迟异步回调(例如在onCreate()方法内部)之外的“主线程”调用这些语句吗? 只要我从“延迟”方法调用相同的语句。在我的例子中是ResultCallback，我得到了相同的消息。

在我的片段中，从ResultCallback方法中调用下面的代码会产生相同的消息。在将代码移动到我的应用程序中的onConnected()方法后，消息消失了…

LinearLayoutManager llm = new LinearLayoutManager(this);
llm.setOrientation(LinearLayoutManager.VERTICAL);
list.setLayoutManager(llm);
list.setAdapter( adapter );

我得到了同样的问题，我做的每件事都是正确的，除了在xml文件:

step first 1: initialize recyclerview & List & Adaptor: RecyclerView recyclerview; List<ModelName> list; ProvideBidAdaptor adaptor; step 2: bind it in onCreate- recyclerview = findByViewId(R.id.providerBidRV); recyclerview.setLayoutManager(new LinearLayoutManager(this)); recyclerview.setHasFixedSize(true); list = new ArrayList<>(); step 3: Where you getting response or list - add list- (i am getting from response)> responseList.addAll(response.getResponse()); adaptor = new ProvideBidAdaptor(this, responseList); binding.detailsRV.setAdapter(adaptor);

这是我的xml文件，我实现RecyclerView: 我忘记了线性布局的方向，经过这个修正- RecyclerView附加。

<?xml version="1.0" encoding="utf-8"?>
    <layout>
    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:app="http://schemas.android.com/apk/res-auto"
        xmlns:tools="http://schemas.android.com/tools"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical"
        tools:context=".activities.Bidding.ProvideBid">

        <include
            android:id="@+id/toolbar"
            layout="@layout/app_toolbar"/>

        <androidx.recyclerview.widget.RecyclerView
            android:id="@+id/providerBidRV"
            android:layout_width="match_parent"
            android:layout_height="match_parent"/>
    </LinearLayout>
</layout> 

这是适配器:

    public class ProvideBidAdaptor extends RecyclerView.Adapter<ProvideBidAdaptor.ViewHolder> {
    Context context;
    List<Response> responseList;
    DateTime dateTimeInstance = new DateTime();

    public ProvideBidAdaptor(Context context, List<Response> responseList) {
        this.context = context;
        this.responseList = responseList;
    }

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

    @Override
    public void onBindViewHolder(@NonNull ViewHolder holder, int position) {
        final Response detailsResponse = responseList.get(position);
        if (!detailsResponse.getUserId().isEmpty()) {

            holder.day.setText(detailsResponse.getDay());
            holder.locationType.setText(detailsResponse.getLocationType());

        }

    }

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

    public class ViewHolder extends RecyclerView.ViewHolder {
        TextView date,locationType;
        CardView provideBidCV;
        LinearLayout dayLLayout,locationTypeLLayout;
        public ViewHolder(@NonNull View itemView) {
            super(itemView);
            date = itemView.findViewById(R.id.date_value);
            day = itemView.findViewById(R.id.day_value);
            locationType = itemView.findViewById(R.id.locationType_value);

            locationTypeLLayout = itemView.findViewById(R.id.locationTypeLLayout);

        }
    }
}

在Kotlin，我们遇到了一个奇怪的不合逻辑的问题。

这并没有起作用:

 mBinding.serviceProviderCertificates.apply {
            adapter = adapter
            layoutManager =  LinearLayoutManager(activity)
        }

虽然这是有效的:

mBinding.serviceProviderCertificates.adapter = adapter
mBinding.serviceProviderCertificates.layoutManager = LinearLayoutManager(activity)

工作之余，我也会分享更多的真知灼见。