当我可以在Firebase中看到费用数据时，为什么我的应用程序中未显示费用数据？

我有2辆推车，一辆有收入，一辆有费用。收入数据显示在Firebase和我的应用程序中。仅在Firebase中可见的费用数据，在应用程序中不可见。有一些代码：ExpenseFragment：

 ///**
    // * A simple {@link Fragment} subclass.
    // * Use the {@link ExpenseFragment#newInstance} factory method to
    // * create an instance of this fragment.
    // */
    public class ExpenseFragment extends Fragment {
    
        private FirebaseAuth mAuth;
        private DatabaseReference mExpenseDatabase;
    
        private RecyclerView recyclerView;
    
    //    // TODO: Rename parameter arguments, choose names that match
    //    // the fragment initialization parameters, e.g. ARG_ITEM_NUMBER
        private static final String ARG_PARAM1 = "param1";
        private static final String ARG_PARAM2 = "param2";
    //
    //    // TODO: Rename and change types of parameters
        private String mParam1;
        private String mParam2;
    //
        public ExpenseFragment() {
            // Required empty public constructor
        }
    //
        /**
         * Use this factory method to create a new instance of
         * this fragment using the provided parameters.
         *
         * @param param1 Parameter 1.
         * @param param2 Parameter 2.
         * @return A new instance of fragment ExpenseFragment.
         */
        // TODO: Rename and change types and number of parameters
       /** public static ExpenseFragment newInstance(String param1, String param2) {
           * ExpenseFragment fragment = new ExpenseFragment();
           * Bundle args = new Bundle();
           * args.putString(ARG_PARAM1, param1);
           * args.putString(ARG_PARAM2, param2);
           * fragment.setArguments(args);
           * return fragment;
        }
        */
    
        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
         /**   if (getArguments() != null) {
               // mParam1 = getArguments().getString(ARG_PARAM1);
               // mParam2 = getArguments().getString(ARG_PARAM2);
            } */
        }
    
        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                                 Bundle savedInstanceState) {
            // Inflate the layout for this fragment
            View myview= inflater.inflate(R.layout.fragment_expense, container, false);
    
            mAuth=FirebaseAuth.getInstance();
    
            FirebaseUser mUser = mAuth.getCurrentUser();
            String uid=mUser.getUid();
    
            mExpenseDatabase= FirebaseDatabase.getInstance().getReference().child("ExpenseData").child(uid);
    
            recyclerView=myview.findViewById(R.id.recycler_id_expense);
    
            LinearLayoutManager layoutManager=new LinearLayoutManager(getActivity());
    
            layoutManager.setStackFromEnd(true);
            layoutManager.setReverseLayout(true);
            recyclerView.setHasFixedSize(true);
            recyclerView.setLayoutManager(layoutManager);
    
            return myview;
        }
    
        @Override
        public void onStart() {
            super.onStart();
    
            FirebaseRecyclerOptions<Data> options=
                    new FirebaseRecyclerOptions.Builder<Data>()
                            .setQuery(mExpenseDatabase,Data.class)
                            .setLifecycleOwner(this)
                            .build();
            FirebaseRecyclerAdapter<Data, MyViewHolder> firebaseRecyclerAdapter = new FirebaseRecyclerAdapter<Data, MyViewHolder>(options) {
                @NonNull
                @Override
                public MyViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
                    return new MyViewHolder(LayoutInflater.from(parent.getContext()).inflate(R.layout.expense_recycler_data,parent,false));
                }
                @Override
                protected void onBindViewHolder(@NonNull MyViewHolder holder, int position, @NonNull Data model) {
    
                    holder.setAmount(model.getAmount());
                    holder.setType(model.getType());
                    holder.setNote(model.getNote());
                    holder.setDate(model.getDate());
                }
            };
            recyclerView.setAdapter(firebaseRecyclerAdapter);
    
        }
    
        public static class MyViewHolder extends  RecyclerView.ViewHolder {
            View mView;
    
            public MyViewHolder(View itemView){
                super(itemView);
                mView=itemView;
            }
    
            private void setDate(String date){
                TextView mDate=mView.findViewById(R.id.date_txt_expense);
                mDate.setText(date);
            }
    
            private void setType(String type){
                TextView mType=mView.findViewById(R.id.type_txt_expense);
                mType.setText(type);
            }
    
            private void setNote(String note){
                TextView mNote=mView.findViewById(R.id.note_txt_expense);
                mNote.setText(note);
            }
    
            private void setAmount(int amount){
                TextView mAmonut=mView.findViewById(R.id.amount_txt_expense);
    
                String stamount=String.valueOf(amount);
    
                mAmonut.setText(stamount);
            }
    
        }
    
    }

xml文件：

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

    <androidx.cardview.widget.CardView
        android:layout_width="match_parent"
        app:cardElevation="5dp"
        android:elevation="10dp"
        android:layout_height="wrap_content">

        <LinearLayout
            android:layout_width="match_parent"
            android:orientation="horizontal"
            android:layout_height="wrap_content">

            <RelativeLayout
                android:layout_width="0dp"
                android:layout_weight="1"
                android:gravity="center"
                android:layout_margin="10dp"
                android:layout_height="wrap_content">

                <TextView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:textAppearance="?android:textAppearanceMedium"
                    android:textColor="@android:color/black"
                    android:text="expense"/>





            </RelativeLayout>

            <RelativeLayout
                android:layout_width="0dp"
                android:layout_weight="3"
                android:gravity="center"
                android:layout_margin="10dp"
                android:layout_height="wrap_content">

                <TextView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:id="@+id/expense_txt_result"
                    android:textAppearance="?android:textAppearanceMedium"
                    android:textColor="@android:color/black"
                    android:text="00.00"/>


            </RelativeLayout>


        </LinearLayout>


    </androidx.cardview.widget.CardView>

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

    </androidx.recyclerview.widget.RecyclerView>

</LinearLayout>

和DashBoardFragment：

///**
// * A simple {@link Fragment} subclass.
// * Use the {@link DashBoardFragment#newInstance} factory method to
// * create an instance of this fragment.
// */
public class DashBoardFragment extends Fragment {

    private FloatingActionButton fab_main_btn;
    private FloatingActionButton fab_income_btn;
    private FloatingActionButton fab_expense_btn;


    //Textview

    private TextView fab_income_txt;
    private TextView fab_expense_txt;


    private boolean isOpen = false;

    //animation

    private Animation FadeOpen, FadeClose;

    //Firebase

    private FirebaseAuth mAuth;
    private DatabaseReference mIncomeDatabase;
    private DatabaseReference mExpenseDatabase;


    // TODO: Rename parameter arguments, choose names that match
    // the fragment initialization parameters, e.g. ARG_ITEM_NUMBER
    private static final String ARG_PARAM1 = "param1";
    private static final String ARG_PARAM2 = "param2";

    // TODO: Rename and change types of parameters
    private String mParam1;
    private String mParam2;

    public DashBoardFragment() {
        // Required empty public constructor
    }

//    /**
//     * Use this factory method to create a new instance of
//     * this fragment using the provided parameters.
//     *
//     * @param param1 Parameter 1.
//     * @param param2 Parameter 2.
//     * @return A new instance of fragment DashBoardFragment.
//     */
    // TODO: Rename and change types and number of parameters
//    public static DashBoardFragment newInstance(String param1, String param2) {
//        DashBoardFragment fragment = new DashBoardFragment();
//        Bundle args = new Bundle();
//        args.putString(ARG_PARAM1, param1);
//        args.putString(ARG_PARAM2, param2);
//        fragment.setArguments(args);
//        return fragment;
//    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
//        if (getArguments() != null) {
//            mParam1 = getArguments().getString(ARG_PARAM1);
//            mParam2 = getArguments().getString(ARG_PARAM2);
//        }
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        View myview = inflater.inflate(R.layout.fragment_dash_board, container, false);

        mAuth = FirebaseAuth.getInstance();

        FirebaseUser mUser = mAuth.getCurrentUser();

        String uid = mUser.getUid();

        mIncomeDatabase = FirebaseDatabase.getInstance().getReference().child("IncomeData").child(uid);
        mExpenseDatabase = FirebaseDatabase.getInstance().getReference().child("ExpenseData").child(uid);

        //połączenie z layoutem floating button

        fab_main_btn = myview.findViewById(R.id.fb_main_plus_btn);
        fab_income_btn = myview.findViewById(R.id.income_ft_btn);
        fab_expense_btn = myview.findViewById(R.id.expense_ft_btn);

        //floating text

        fab_income_txt = myview.findViewById(R.id.income_ft_text);
        fab_expense_txt = myview.findViewById(R.id.expense_ft_text);


        //anim connect

        FadeOpen = AnimationUtils.loadAnimation(getActivity(), R.anim.fade_open);
        FadeClose = AnimationUtils.loadAnimation(getActivity(), R.anim.fade_close);


        fab_main_btn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {

                addData();

                if (isOpen) {
                    fab_income_btn.startAnimation(FadeClose);
                    fab_expense_btn.startAnimation(FadeClose);
                    fab_income_btn.setClickable(false);
                    fab_expense_btn.setClickable(false);

                    fab_income_txt.startAnimation(FadeClose);
                    fab_expense_txt.startAnimation(FadeClose);
                    fab_income_txt.setClickable(false);
                    fab_expense_txt.setClickable(false);
                    isOpen = false;
                } else {
                    fab_income_btn.startAnimation(FadeOpen);
                    fab_expense_btn.startAnimation(FadeOpen);
                    fab_income_btn.setClickable(true);
                    fab_expense_btn.setClickable(true);

                    fab_income_txt.startAnimation(FadeOpen);
                    fab_expense_txt.startAnimation(FadeOpen);
                    fab_income_txt.setClickable(true);
                    fab_expense_txt.setClickable(true);
                    isOpen = true;

                }

            }
        });


        return myview;
    }

    private void ftAnimation(){
        if (isOpen) {
            fab_income_btn.startAnimation(FadeClose);
            fab_expense_btn.startAnimation(FadeClose);
            fab_income_btn.setClickable(false);
            fab_expense_btn.setClickable(false);

            fab_income_txt.startAnimation(FadeClose);
            fab_expense_txt.startAnimation(FadeClose);
            fab_income_txt.setClickable(false);
            fab_expense_txt.setClickable(false);
            isOpen = false;
        } else {
            fab_income_btn.startAnimation(FadeOpen);
            fab_expense_btn.startAnimation(FadeOpen);
            fab_income_btn.setClickable(true);
            fab_expense_btn.setClickable(true);

            fab_income_txt.startAnimation(FadeOpen);
            fab_expense_txt.startAnimation(FadeOpen);
            fab_income_txt.setClickable(true);
            fab_expense_txt.setClickable(true);
            isOpen = true;

        }
    }


    private void addData() {

        fab_income_btn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                incomeDataInsert();

            }
        });

        fab_expense_btn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                expenseDataInsert();

            }
        });

    }


    public void incomeDataInsert() {

        AlertDialog.Builder mydialog = new AlertDialog.Builder(getActivity());
        LayoutInflater inflater = LayoutInflater.from(getActivity());
        View myview = inflater.inflate(R.layout.custom_layout_for_insertdata, null);
        mydialog.setView(myview);

        final AlertDialog dialog = mydialog.create();



        dialog.setCancelable(false);
        final EditText edtAmount = myview.findViewById(R.id.amount_edt);
        final EditText edtType = myview.findViewById(R.id.typ_edt);
        final EditText edtNote = myview.findViewById(R.id.note_edt);

        Button btnSave = myview.findViewById(R.id.btnSave);
        Button btnCancel = myview.findViewById(R.id.btnCancel);

        btnSave.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                String type = edtType.getText().toString().trim();
                String amount = edtAmount.getText().toString().trim();
                String note = edtNote.getText().toString().trim();

                if (TextUtils.isEmpty(type)) {
                    edtType.setError("Field required");
                    return;
                }

                if (TextUtils.isEmpty(amount)) {
                    edtAmount.setError("Field required");
                    return;
                }

                int ouramountint = Integer.parseInt(amount);

                if (TextUtils.isEmpty(note)) {
                    edtNote.setError("Field required");
                    return;
                }

                String id = mIncomeDatabase.push().getKey();
                String mDate = DateFormat.getDateInstance().format(new Date());

                Data data = new Data(ouramountint, type, note, id, mDate);

                mIncomeDatabase.child(id).setValue(data);
                Toast.makeText(getActivity(), "Data Added", Toast.LENGTH_SHORT).show();

                ftAnimation();
                dialog.dismiss();


            }
        });

        btnCancel.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                ftAnimation();
                dialog.dismiss();
            }
        });
        dialog.show();
    }

    public void expenseDataInsert() {
        AlertDialog.Builder mydialog = new AlertDialog.Builder(getActivity());
        LayoutInflater inflater = LayoutInflater.from(getActivity());
        View myview = inflater.inflate(R.layout.custom_layout_for_insertdata, null);
        mydialog.setView(myview);

       final AlertDialog dialog =mydialog.create();

        dialog.setCancelable(false);

       final EditText amount = myview.findViewById(R.id.amount_edt);
       final EditText type = myview.findViewById(R.id.typ_edt);
       final EditText note = myview.findViewById(R.id.note_edt);

        Button btnSave = myview.findViewById(R.id.btnSave);
        Button btnCancel = myview.findViewById(R.id.btnCancel);

        btnSave.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                String tmAmount=amount.getText().toString().trim();
                String tmtype=type.getText().toString().trim();
                String tmnote=note.getText().toString().trim();

                if (TextUtils.isEmpty(tmAmount)){
                    amount.setError("Required field");
                    return;
                }

                int inamount=Integer.parseInt(tmAmount);

                if (TextUtils.isEmpty(tmtype)){
                    type.setError("Required field");
                    return;
                }
                if (TextUtils.isEmpty(tmnote)){
                    note.setError("Required field");
                    return;
                }

                String id=mExpenseDatabase.push().getKey();
                String mDate=DateFormat.getDateInstance().format(new Date());

                Data data=new Data(inamount,tmtype,tmnote,id,mDate);
                mExpenseDatabase.child(id).setValue(data);

                Toast.makeText(getActivity(),"Data added",Toast.LENGTH_SHORT).show();

                ftAnimation();
                dialog.dismiss();

            }
        });

    btnCancel.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            ftAnimation();
            dialog.dismiss();
        }
    });

    dialog.show();

    }

}

和IncomeFragment（核心地工作）进行比较：

///**
// * A simple {@link Fragment} subclass.
// * Use the {@link IncomeFragment#newInstance} factory method to
// * create an instance of this fragment.
// */
public class IncomeFragment extends Fragment {

   //Database

    private FirebaseAuth mAuth;
    private DatabaseReference mIncomeDatabase;

    //Recyvlerview

    private RecyclerView recyclerView;

    private TextView incomeTotalSum;


    // TODO: Rename parameter arguments, choose names that match
    // the fragment initialization parameters, e.g. ARG_ITEM_NUMBER
    private static final String ARG_PARAM1 = "param1";
    private static final String ARG_PARAM2 = "param2";

    // TODO: Rename and change types of parameters
    private String mParam1;
    private String mParam2;

    public IncomeFragment() {
        // Required empty public constructor
    }

    /**
     * Use this factory method to create a new instance of
     * this fragment using the provided parameters.
     *
     * @param param1 Parameter 1.
     * @param param2 Parameter 2.
     * @return A new instance of fragment IncomeFragment.
     */
    // TODO: Rename and change types and number of parameters

    /**
     * public static IncomeFragment newInstance(String param1, String param2) {
     * IncomeFragment fragment = new IncomeFragment();
     * Bundle args = new Bundle();
     * args.putString(ARG_PARAM1, param1);
     * args.putString(ARG_PARAM2, param2);
     * fragment.setArguments(args);
     * return fragment;
     * }
     */

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        /**if (getArguments() != null) {
         //mParam1 = getArguments().getString(ARG_PARAM1);
         //mParam2 = getArguments().getString(ARG_PARAM2);
         }*/
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        View myview= inflater.inflate(R.layout.fragment_income, container, false);

        mAuth = FirebaseAuth.getInstance();
        FirebaseUser mUser=mAuth.getCurrentUser();
        String uid=mUser.getUid();


        mIncomeDatabase= FirebaseDatabase.getInstance().getReference().child("IncomeData").child(uid);

        incomeTotalSum=myview.findViewById(R.id.income_txt_result);

        recyclerView=myview.findViewById(R.id.recycler_id_income);

        LinearLayoutManager layoutManager=new LinearLayoutManager(getActivity());

        layoutManager.setReverseLayout(true);
        layoutManager.setStackFromEnd(true);
        recyclerView.setHasFixedSize(true);
        recyclerView.setLayoutManager(layoutManager);


        mIncomeDatabase.addValueEventListener(new ValueEventListener() {
            @Override
            public void onDataChange(@NonNull DataSnapshot dataSnapshot) {

                int totalvalue = 0;

                for (DataSnapshot mysnapshot:dataSnapshot.getChildren()){
                    Data data=mysnapshot.getValue(Data.class);
                    totalvalue+=data.getAmount();

                    String stTotalvalue=String.valueOf(totalvalue);

                    incomeTotalSum.setText(stTotalvalue);
                }
            }


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

            }
        });

        return myview;
    }

    @Override
    public void onStart() {
        super.onStart();

        FirebaseRecyclerOptions<Data> options=
                new FirebaseRecyclerOptions.Builder<Data>()
                        .setQuery(mIncomeDatabase,Data.class)
                        .setLifecycleOwner(this)
                        .build();
        FirebaseRecyclerAdapter<Data, MyViewHolder> firebaseRecyclerAdapter = new FirebaseRecyclerAdapter<Data, MyViewHolder>(options) {
            @NonNull
            @Override
            public MyViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
                return new MyViewHolder(LayoutInflater.from(parent.getContext()).inflate(R.layout.income_recycler_data,parent,false));
            }
            @Override
            protected void onBindViewHolder(@NonNull MyViewHolder holder, int position, @NonNull Data model) {

                holder.setAmount(model.getAmount());
                holder.setType(model.getType());
                holder.setNote(model.getNote());
                holder.setDate(model.getDate());
            }
        };
        recyclerView.setAdapter(firebaseRecyclerAdapter);
    }


         public static class MyViewHolder extends RecyclerView.ViewHolder {

            View mView;

            public MyViewHolder(@NonNull View itemView) {
                super(itemView);
                mView = itemView;
            }

            private void setType(String type) {
                TextView mType = mView.findViewById(R.id.type_txt_income);
                mType.setText(type);
            }

            private void setNote(String note) {
                TextView mNote = mView.findViewById(R.id.note_txt_income);
                mNote.setText(note);
            }

            private void setDate(String date) {
                TextView mDate = mView.findViewById(R.id.date_txt_income);
                mDate.setText(date);
            }

            private void setAmount(int amount) {
                TextView mAmount = mView.findViewById(R.id.amount_txt_income);
                String stamount = String.valueOf(amount);
                mAmount.setText(stamount);

我没有收到任何错误...我可以在firebase数据库中看到费用数据，但在应用程序中看不到。不要关注“总计”片段中的差异，因为没有这些，费用数据应该是可见的。

感谢您的任何帮助。