RecyclerView Android中的微调器

Question

我正在开发一个应用程序，其中有一个更新数据活动来修改以前的数据。在此，我创建了一个回收站视图。我想从Firebase数据库中获取数据，并根据Firebase中的值设置微调器。我正在使用微调器中的数据适配器，因此，当我尝试使用spn.getSelectedItemPosition（）在微调器中查找数据索引并在其上传递字符串时，它表明在使用微调器适配器时字符串不起作用。如何在回收器视图中使用微调器，请提供帮助。这是我的代码：

public class ArrangementAdminAdapter extends RecyclerView.Adapter<ArrangementAdminAdapter.ArrangementAdminHolder> {

    ArrayList<Arrangements> list;
    public ArrangementAdminAdapter(ArrayList<Arrangements> list){
        this.list = list;
    }

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

        LayoutInflater inflater = LayoutInflater.from(parent.getContext());
        View view = inflater.inflate(R.layout.arrangement_admin_update,parent,false);
        return new ArrangementAdminHolder(view);
    }

    @Override
    public void onBindViewHolder(@NonNull ArrangementAdminHolder holder, int position) {

        Arrangements a = list.get(position);
        holder.date.setText(a.getDate());

    }

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

    public class ArrangementAdminHolder extends RecyclerView.ViewHolder {

        EditText date;
        Spinner spnTeacher, spnArrangedBy, spnClass, spnTime;

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

            date = itemView.findViewById(R.id.arrangement_date);
            spnTeacher = itemView.findViewById(R.id.spnTeacher);
            spnClass = itemView.findViewById(R.id.spnClass);
            spnArrangedBy = itemView.findViewById(R.id.spnArrangedBy);
            spnTime = itemView.findViewById(R.id.spnTime);
            LoadTeacherSpinner();
            LoadClassSpinner();
            LoadTimeSpinner();

        }

        public void LoadTeacherSpinner(){
            ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(itemView.getContext(),
                    R.array.teachers_array, android.R.layout.simple_spinner_item);

            adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
            spnTeacher.get
            spnTeacher.setAdapter(adapter);
            spnArrangedBy.setAdapter(adapter);

        }

        public void LoadClassSpinner(){
            ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(itemView.getContext(),
                    R.array.class_array, android.R.layout.simple_list_item_1);

            adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);

            spnClass.setAdapter(adapter);


        }

        public void LoadTimeSpinner(){
            ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(itemView.getContext(),
                    R.array.time_array, android.R.layout.simple_spinner_item);

            adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);

            spnTime.setAdapter(adapter);

        }
    }
}