Get object data out of this databaseReference.addValueEventListener in java android

Question

here is the samplae code what I want to do is, get json object or string out of this data databaseReference.addValueEventListener(new ValueEventListener() thing and use it anywhere I want not only inside this database thing

import android.os.Build;
import android.os.Bundle;


import android.util.Log;
import android.widget.Button;

import android.widget.Toast;

import androidx.annotation.NonNull;
import androidx.annotation.RequiresApi;
import androidx.appcompat.app.AppCompatActivity;


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.ValueEventListener;
import com.google.gson.Gson;

import org.json.JSONException;
import org.json.JSONObject;

import java.util.Objects;

public class MainActivity extends AppCompatActivity {
    FirebaseDatabase firebaseDatabase;
    DatabaseReference databaseReference;

    Button photo;
    public String da;
    public String fx;
    Object databaseValues;

    @RequiresApi(api = Build.VERSION_CODES.M)
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        photo = findViewById(R.id.light);
        firebaseDatabase = FirebaseDatabase.getInstance();
        databaseReference = firebaseDatabase.getReference();
        databaseReference.addValueEventListener(new ValueEventListener() {
            @RequiresApi(api = Build.VERSION_CODES.S)
            @Override
            public void onDataChange(@NonNull DataSnapshot snapshot) {
                databaseValues = snapshot.getValue(Object.class);
                String value = new Gson().toJson(databaseValues);
                JSONObject jsonObj;

                try {
                    jsonObj = new JSONObject(value);
                    da = jsonObj.getString("test");
                    Log.i("databaseValue inside: ", da);
                } catch (JSONException e) {
                    e.printStackTrace();
                }
            }

            @Override
            public void onCancelled(@NonNull DatabaseError error) {
                Toast.makeText(MainActivity.this, "Fail to get data.", Toast.LENGTH_SHORT).show();
            }
        });

        try {
            String value = new Gson().toJson(databaseValues);
            JSONObject jsonObj;
            jsonObj = new JSONObject(value);
            fx = jsonObj.getString("test");
        } catch (JSONException e) {
            e.printStackTrace();
        }
        if (Objects.equals(da, "found")) {
            photo.setBackgroundColor(getResources().getColor(R.color.white));
        }
        if (da == null){
            Log.i("databaseValue: ", "null");
        } else {
            Log.i("databaseValue: ", da);
        }
        if (fx == null){
            Log.i("fx: ", "null");
        } else {
            Log.i("fx: ", fx);
        }
    }
}

I'm getting databaseValue null and fx null but databaseVale inside is found, i want this data to be outside.