Recyclerview没有显示任何内容，任何想法？使用FirestoreUI RecyclerAdapter

Question

下面的代码似乎已经完成了所需的一切，但是仅仅没有填充Recyclerview。

我甚至把Log on OnDateChange看看它是否被调用，并且在我在Galaxy S6上运行它之后在LogCat上调用了一次。此外，数据库是公开的。

RecyclerView chat_view;
EditText message_text;

CollectionReference reference = FirebaseFirestore.getInstance().collection("stage2");
Query query = reference.orderBy("timestamp");
FirestoreRecyclerAdapter<ChatMessage,ChatHolder> adapter=null;




@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_chat);
    //initializing, called below
    init();
}





private FirestoreRecyclerAdapter<ChatMessage,ChatHolder> newAdapter() {
    final FirestoreRecyclerOptions options = new FirestoreRecyclerOptions.Builder<ChatMessage>()
            .setQuery(query,ChatMessage.class)
            .setLifecycleOwner(this)                
                            .build();

    return new FirestoreRecyclerAdapter<ChatMessage, ChatHolder>(options) {
        @Override
        public ChatHolder onCreateViewHolder(ViewGroup parent, int viewType) {
           View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.chat_item,parent,false);
            //if(((ChatMessage)options.getSnapshots().getSnapshot(viewType)).)
            return new ChatHolder(view);
        }

        @Override
        protected void onBindViewHolder(ChatHolder holder, int position, ChatMessage model) {         




            //displaying the message and users into the recyclerview
            holder.user_msg.setText(model.getMessage());
            holder.user_date.setText(model.getDate());
            holder.user_name.setText(model.getName());

        }




        @Override
        public void onDataChanged() {
            Log.d("TAG", "YESSIR");

        }

        @Override
        public void onError(FirebaseFirestoreException e) {
            super.onError(e);
        }
    };




}

private void init(){
    chat_view = (RecyclerView) findViewById(R.id.chat_view);
    chat_view.setVerticalScrollBarEnabled(true);
    LinearLayoutManager layoutManager = new LinearLayoutManager(this);

    chat_view.setLayoutManager(layoutManager);
    adapter = newAdapter();
    chat_view.setAdapter(adapter);




    message_text = (EditText) findViewById(R.id.message_text);
    message_text.setEnabled(appUtils.isSignedIn());
    findViewById(R.id.send_button).setEnabled(appUtils.isSignedIn());




}

所以，我们有它，我不知道此时问题是什么。我也在使用最新的Firestore UI依赖项。

Answer 1

看来你已经做了所有必要的事情......使用FirestoreRecycleroptions并在onCreateViewHolder中扩充布局。

为了使FirestoreRecyclerAdapter能够获得活动数据，那么你需要听听onStart()之后的onCreate()的任何变化。同样在onStop你可以停止听。

    @Override
public void onStart() {
    super.onStart();
    adapter.startListening();
}

@Override
public void onStop() {
    super.onStop();
    adapter.stopListening();
}