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I have successfully retrieved one-time query for my first activity but at the second activity that I wanted to use the query it cannot work can someone help to solve it?

this is my firebase database

"food" : {

    "-LTHH-aVp3zAkkUHrO70" : {

      "foodId" : "-LTHH-aVp3zAkkUHrO70",

      "foodName" : "Char Keoy Tiaw",

      "foodType" : "Breakfast"

    },

    "-LTHWNfyDCzGoMSASjeP" : {

      "foodId" : "-LTHWNfyDCzGoMSASjeP",

      "foodName" : "Sandwich",

      "foodType" : "Breakfast"

    },

    "-LTHdfW1oNVz9iB8oIv9" : {

      "foodId" : "-LTHdfW1oNVz9iB8oIv9",

      "foodName" : "MEE",

      "foodType" : "Breakfast"

    },

    "-LTLwn3D3gkbKoLmOa-9" : {

      "foodId" : "-LTLwn3D3gkbKoLmOa-9",

      "foodName" : "Egg",

      "foodType" : "Breakfast"

    }

This is my success retrieve data activity

package com.example.asus.mobilefoodpicker;



import android.os.Bundle;

import android.support.annotation.NonNull;

import android.support.v7.app.AlertDialog;

import android.support.v7.app.AppCompatActivity;

import android.text.TextUtils;

import android.view.LayoutInflater;

import android.view.View;

import android.widget.AdapterView;

import android.widget.Button;

import android.widget.EditText;

import android.widget.ListView;

import android.widget.Spinner;

import android.widget.TextView;

import android.widget.Toast;



import com.google.firebase.database.DataSnapshot;

import com.google.firebase.database.DatabaseError;

import com.google.firebase.database.DatabaseReference;

import com.google.firebase.database.FirebaseDatabase;

import com.google.firebase.database.Query;

import com.google.firebase.database.ValueEventListener;

import java.util.ArrayList;

import java.util.List;



public class Activity2 extends AppCompatActivity {



private Button sbtn;

private Foodlist adapter;

DatabaseReference databasemobilefoodpicker;

ListView listViewFood;



List<Food> foodlists;





@Override

protected void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);

    setContentView(R.layout.activity_2);

    databasemobilefoodpicker = 

FirebaseDatabase.getInstance().getReference("food");







databasemobilefoodpicker.addListenerForSingleValueEvent

(valueEventListener);

    Query query = FirebaseDatabase.getInstance().getReference("food")

            .orderByChild("foodType")

            .equalTo("Breakfast");



    query.addListenerForSingleValueEvent(valueEventListener);





    foodlists = new ArrayList<>();



    listViewFood = (ListView) findViewById(R.id.listViewFood);

    adapter = new Foodlist(Activity2.this, foodlists);

    listViewFood.setAdapter(adapter);















}





@Override

protected void onStart() {

    super.onStart();

    databasemobilefoodpicker.addValueEventListener(new ValueEventListener() 

 {

        @Override

        public void onDataChange(DataSnapshot dataSnapshot) {



            foodlists.clear();



            for(DataSnapshot foodSnapshot : dataSnapshot.getChildren()){

                Food food = foodSnapshot.getValue(Food.class);



                foodlists.add(food);

            }



            Foodlist adapter = new Foodlist(Activity2.this, foodlists);

            listViewFood.setAdapter(adapter);

        }



        @Override

        public void onCancelled( DatabaseError databaseError) {



        }

    });

    listViewFood.setOnItemLongClickListener(new 

AdapterView.OnItemLongClickListener() {

        @Override

        public boolean onItemLongClick(AdapterView<?> parent, View view, 

int position, long id) {



            Food food = foodlists.get(position);



            showUpdateDialog(food.getFoodId(),food.getFoodName());

            return false;

        }

    });

}

ValueEventListener valueEventListener = new ValueEventListener() {

    @Override

    public void onDataChange(@NonNull DataSnapshot dataSnapshot) {

        foodlists.clear();

        if (dataSnapshot.exists()) {

            for (DataSnapshot snapshot : dataSnapshot.getChildren()){

                Food food = snapshot.getValue(Food.class);

                foodlists.add(food);

            }

            adapter.notifyDataSetChanged();

        }

    }



    @Override

    public void onCancelled(@NonNull DatabaseError databaseError) {



    }

};







private void showUpdateDialog(final String foodId, String foodName){



    AlertDialog.Builder dialogBuilder = new AlertDialog.Builder(this);



    LayoutInflater inflater = getLayoutInflater();



    final View dialogView = inflater.inflate(R.layout.update_dialog,null);



    dialogBuilder.setView(dialogView);



    final TextView textViewName = (TextView) 

dialogView.findViewById(R.id.textViewName);

    final EditText editTextName = (EditText) 

dialogView.findViewById(R.id.editTextName);

    final Button buttonUpdate = (Button) 

dialogView.findViewById(R.id.buttonUpdate);

    final Spinner spinnerfoodtype = (Spinner) 

dialogView.findViewById(R.id.spinnertype);

    final Button buttonDelete = (Button) 

dialogView.findViewById(R.id.buttonDelete);



    dialogBuilder.setTitle("Updating Food:  " + foodName);



    final AlertDialog alertDialog = dialogBuilder.create();

    alertDialog.show();



    buttonUpdate.setOnClickListener(new View.OnClickListener() {

        @Override

        public void onClick(View v) {

            String name = editTextName.getText().toString().trim();

            String type = spinnerfoodtype.getSelectedItem().toString();



            if(TextUtils.isEmpty(name)){

                editTextName.setError("Food Name Required");

                return;

            }



            updateFood(foodId, name, type);



            alertDialog.dismiss();



        }

    });

    buttonDelete.setOnClickListener(new View.OnClickListener() {

        @Override

        public void onClick(View v) {

            deleteFood(foodId);

            alertDialog.dismiss();



        }

    });

}



private void deleteFood(String foodId){

    DatabaseReference drFood =  

FirebaseDatabase.getInstance().getReference("food").child(foodId);



    drFood.removeValue();



    Toast.makeText(this,"Food is deleted", Toast.LENGTH_LONG).show();

}



private boolean updateFood(String id, String name, String type){

    DatabaseReference databaseReference = 

FirebaseDatabase.getInstance().getReference("food").child(id);



    Food food = new Food(id, name, type);



    databaseReference.setValue(food);



    Toast.makeText(this,"Food Updated Successfully", 

Toast.LENGTH_LONG).show();



    return true;

}



}

the activity that did not success retrieve the query data

package com.example.asus.mobilefoodpicker;



import android.support.annotation.NonNull;

import android.support.v7.app.AppCompatActivity;

import android.os.Bundle;

import android.widget.Button;

import android.widget.ListView;



import com.google.firebase.database.DataSnapshot;

import com.google.firebase.database.DatabaseError;

import com.google.firebase.database.DatabaseReference;

import com.google.firebase.database.FirebaseDatabase;

import com.google.firebase.database.Query;

import com.google.firebase.database.ValueEventListener;



import java.util.ArrayList;

import java.util.List;



public class Activity4 extends AppCompatActivity {

private Button sbtn;

private Foodlist adapter;

DatabaseReference databasemobilefoodpicker;

ListView list;



List<Food> foodlists1;

@Override

protected void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);

    setContentView(R.layout.activity_4);



    databasemobilefoodpicker = 

FirebaseDatabase.getInstance().getReference("food");

    databasemobilefoodpicker.addListenerForSingleValueEvent

(valueEventListener);

    Query query4 = FirebaseDatabase.getInstance().getReference("foodType")

            .orderByChild("foodType")

            .equalTo("Dinner");



    query4.addListenerForSingleValueEvent(valueEventListener);





    foodlists1 = new ArrayList<>();



    list = (ListView) findViewById(R.id.list);

    adapter = new Foodlist(Activity4.this, foodlists1);

    list.setAdapter(adapter);





}

ValueEventListener valueEventListener = new ValueEventListener() {

    @Override

    public void onDataChange(@NonNull DataSnapshot dataSnapshot) {

        foodlists1.clear();

        if (dataSnapshot.exists()) {

            for (DataSnapshot snapshot : dataSnapshot.getChildren()){

                Food food = snapshot.getValue(Food.class);

                foodlists1.add(food);

            }

            adapter.notifyDataSetChanged();

        }

    }



    @Override

    public void onCancelled(@NonNull DatabaseError databaseError) {



    }

};

}