Java Firestore数据未显示在表格布局的RecyclerView中

我在一张表格里有两个碎片。数据不能在RecyclerView中显示，但数量正确，我可以在logcat中显示数据，但不能在RecyclerView中显示

Fragment_users.java

public class Fragment_users extends Fragment {
    private static final String TAG = "Fragment_users";

    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View rootView=inflater.inflate(R.layout.fragment_users,container,false);
        dataModalArrayList = new ArrayList<>();
        db = FirebaseFirestore.getInstance();
        coursesLV = (RecyclerView) rootView.findViewById(R.id.usersRView);
        coursesLV.setLayoutManager(new LinearLayoutManager(getContext(),LinearLayoutManager.HORIZONTAL,false));

        loadDatainListview();
        return rootView;
    }

    RecyclerView coursesLV;
    ArrayList<users> dataModalArrayList;
    FirebaseFirestore db;
    ViewPager holder;

    private void loadDatainListview() {
        db.collection("users").whereEqualTo("isUser", true).get()
                .addOnCompleteListener(new OnCompleteListener<QuerySnapshot>() {
                    @Override
                    public void onComplete(@NonNull Task<QuerySnapshot> task) {
                        if (task.isSuccessful()) {
                            for (QueryDocumentSnapshot document : task.getResult()) {
                                Log.d(TAG, document.getId() + " => " + document.getData());
                            }
                        } else {
                            Log.d(TAG, "Error getting documents: ", task.getException());
                        }
                    }
                })
                .addOnSuccessListener(new OnSuccessListener<QuerySnapshot>() {
                    @Override
                    public void onSuccess(QuerySnapshot queryDocumentSnapshots) {
                        if (!queryDocumentSnapshots.isEmpty()) {
                            List<DocumentSnapshot> list = queryDocumentSnapshots.getDocuments();
                            for (DocumentSnapshot d : list) {
                                users dataModal = d.toObject(users.class);
                                dataModalArrayList.add(dataModal);
                            }
                            CustomAdapter adapter = new CustomAdapter(dataModalArrayList);
                            coursesLV.setAdapter(adapter);
                        } else {
                            Log.d(TAG, "No data found in Database");
                        }
                    }
                }).addOnFailureListener(new OnFailureListener() {
            @Override
            public void onFailure(@NonNull Exception e) {
                Toast.makeText(getContext(), "Fail to load data.", Toast.LENGTH_SHORT).show();
                Log.d(TAG, "onFailure: Cannot load data. " + e.toString());
            }
        });
    }

    @Override
    public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);

        CustomAdapter adapter = new CustomAdapter(dataModalArrayList);
        RecyclerView recyclerView = (RecyclerView) view.findViewById(R.id.usersRView);
        LinearLayoutManager layoutManager = new LinearLayoutManager(getContext());
        recyclerView.setLayoutManager(layoutManager);
        recyclerView.setAdapter(adapter);

    }
}

CustomAdapter.java

public class CustomAdapter extends RecyclerView.Adapter<CustomAdapter.MyHolder> {
ArrayList<users> list = new ArrayList<>();
    CustomAdapter.ItemClickListener itemClickListener;

    public CustomAdapter(ArrayList<users> list) {
        this.list = list;
    }

    @NotNull
    @Override
    public MyHolder onCreateViewHolder(ViewGroup parent, int viewType) {

        View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.cardview_addnewadmin,parent,false);

        return new MyHolder(view);
    }

    @Override
    public void onBindViewHolder(MyHolder holder, final int position) {

        final users userData = list.get(position);

        holder.listViewText.setText(userData.getFullName());
        Picasso.get().load(userData.getImgUrl()).into(holder.listViewImg);

        holder.upgradeUser.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                itemClickListener.OnItemClick(position,userData);
                notifyDataSetChanged();
            }
        });
    }

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

    public interface ItemClickListener {

        void OnItemClick(int position,users userData);
    }

    public static class MyHolder extends RecyclerView.ViewHolder{

        TextView listViewText;
        ImageView listViewImg;
        Button upgradeUser;

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

            listViewText = itemView.findViewById(R.id.listViewText);
            listViewImg = itemView.findViewById(R.id.listViewImg);
            upgradeUser = itemView.findViewById(R.id.upgradeUser);
        }
    }

    public void setOnItemClickListener(ItemClickListener itemClickListener){
        this.itemClickListener = (CustomAdapter.ItemClickListener) itemClickListener;
    }

    public void UpdateData(int position,users userData){

        list.remove(position);
        list.add(userData);
        notifyItemChanged(position);
        notifyDataSetChanged();
    }
}

公共类CustomAdapter扩展了RecyclerView.Adapter{ ArrayList=新建ArrayList（）； CustomAdapter.ItemClickListener ItemClickListener； 公共CustomAdapter（ArrayList列表）{ this.list=列表； } @NotNull @凌驾 public MyHolder onCreateViewHolder（视图组父级，int-viewType）{ View View=LayoutInflater.from（parent.getContext（））.flate（R.layout.cardwiew\u addnewadmin，parent，false）； 返回新的MyHolder（视图）； } @凌驾 公共无效onBindViewHolder（MyHolder，最终整数位置）{ 最终用户userData=list.get（位置）； holder.listViewText.setText（userData.getFullName（））； Picasso.get（）.load（userData.getImgUrl（））.into（holder.listViewImg）； holder.upgradeUser.setOnClickListener（新视图.OnClickListener（）{ @凌驾 公共void onClick（视图）{ itemClickListener.OnItemClick（位置、用户数据）； notifyDataSetChanged（）； } }); } @凌驾 public int getItemCount（）{ 返回list.size（）； } 公共接口项ClickListener{ void OnItemClick（int位置，用户userData）； } 公共静态类MyHolder扩展了RecyclerView.ViewHolder{ 文本视图列表视图文本； 图像视图列表视图img； 按钮升级用户； 公共MyHolder（查看项目视图）{ 超级（项目视图）； listViewText=itemView.findViewById（R.id.listViewText）； listViewImg=itemView.findViewById（R.id.listViewImg）； upgradeUser=itemView.findViewById（R.id.upgradeUser）； } } public void setOnItemClickListener（项ClickListener项ClickListener）{ this.itemClickListener=（CustomAdapter.itemClickListener）itemClickListener； } public void UpdateData（int位置，用户userData）{ 列表。删除（位置）； 添加（用户数据）； （职位）变更； notifyDataSetChanged（）； } } 输出： 日志：

请帮我指出哪里错了。谢谢你的阅读。祝你今天愉快：）

public class CustomAdapter extends RecyclerView.Adapter<CustomAdapter.MyHolder> {
ArrayList<users> list = new ArrayList<>();
    CustomAdapter.ItemClickListener itemClickListener;

    public CustomAdapter(ArrayList<users> list) {
        this.list = list;
    }

    @NotNull
    @Override
    public MyHolder onCreateViewHolder(ViewGroup parent, int viewType) {

        View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.cardview_addnewadmin,parent,false);

        return new MyHolder(view);
    }

    @Override
    public void onBindViewHolder(MyHolder holder, final int position) {

        final users userData = list.get(position);

        holder.listViewText.setText(userData.getFullName());
        Picasso.get().load(userData.getImgUrl()).into(holder.listViewImg);

        holder.upgradeUser.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                itemClickListener.OnItemClick(position,userData);
                notifyDataSetChanged();
            }
        });
    }

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

    public interface ItemClickListener {

        void OnItemClick(int position,users userData);
    }

    public static class MyHolder extends RecyclerView.ViewHolder{

        TextView listViewText;
        ImageView listViewImg;
        Button upgradeUser;

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

            listViewText = itemView.findViewById(R.id.listViewText);
            listViewImg = itemView.findViewById(R.id.listViewImg);
            upgradeUser = itemView.findViewById(R.id.upgradeUser);
        }
    }

    public void setOnItemClickListener(ItemClickListener itemClickListener){
        this.itemClickListener = (CustomAdapter.ItemClickListener) itemClickListener;
    }

    public void UpdateData(int position,users userData){

        list.remove(position);
        list.add(userData);
        notifyItemChanged(position);
        notifyDataSetChanged();
    }
}