未连接适配器，在“回收”视图中跳过布局

Question

我尝试运行代码，但在模拟器上却什么也没有显示，我还使用firebase来获取包括图像和文本的数据

    //send Query to FirebaseDatabase
    mFirebaseDatabase = FirebaseDatabase.getInstance();
    mRef = mFirebaseDatabase.getReference().child("Owner").child(uid);
    mRef.addValueEventListener(new ValueEventListener() {
        @Override
        public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
            String stallId = dataSnapshot.child("stallid").getValue().toString();
            String school = dataSnapshot.child("school").getValue().toString();

            xRef = mFirebaseDatabase.getReference().child("menu").child("school").child(school).child("stall").child(stallId).child("food");
            options = new FirebaseRecyclerOptions.Builder<Model>().setQuery(xRef, Model.class).build();

            adapter = new FirebaseRecyclerAdapter<Model, ViewHolder>(options) {
                @Override
                protected void onBindViewHolder(@NonNull ViewHolder viewHolder, int i, @NonNull Model model) {

                    Picasso.get().load(model.getImageurl()).into(viewHolder.i1, new Callback() {
                        @Override
                        public void onSuccess() {

                        }

                        @Override
                        public void onError(Exception e) {
                            Toast.makeText(getApplicationContext(), e.getMessage(), Toast.LENGTH_LONG).show();
                        }
                    });

                    viewHolder.t1.setText(model.getName());
                    viewHolder.t2.setText(model.getPrice());
                }

                @NonNull
                @Override
                public ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {

                    View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.row,parent,false);
                    return new ViewHolder(view);
                }
            };

            GridLayoutManager gridLayoutManager = new GridLayoutManager(getApplicationContext(),2);
            mRecyclerView.setLayoutManager(gridLayoutManager);
            adapter.startListening();
            mRecyclerView.setAdapter(adapter);


        }

        @Override
        public void onCancelled(@NonNull DatabaseError databaseError) {

        }
    });



}

}

我希望显示输出，但是输出为空白，并且显示E / RecyclerView：未连接适配器；跳过布局