I am making an expense manager via firebase but my Android Studio 2021.3 cannot resolve the symbol of FirebaseRecyclerOptions<> even my app is successfully connected with Firebase and configured correctly to Firebase Realtime Database.

Seems build.gradle dependencies are synchronized and OK. I need someone's help.

package com.example.budgetingapp;

import androidx.annotation.NonNull;
import androidx.appcompat.app.AlertDialog;
import androidx.appcompat.app.AppCompatActivity;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;

import android.app.ProgressDialog;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Spinner;
import android.widget.TextView;
import android.widget.Toast;

import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.Task;
import com.google.android.material.floatingactionbutton.FloatingActionButton;
import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;

import org.joda.time.DateTime;
import org.joda.time.Months;
import org.joda.time.MutableDateTime;

import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.zip.DataFormatException;

public class BudgetActivity extends AppCompatActivity {

    private TextView totalBudgetAmountTextView;
    private RecyclerView recyclerView;

    private FloatingActionButton fab;

    private DatabaseReference budgetRef;

    private FirebaseAuth mAuth;
    private ProgressDialog loader;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_budget);

        mAuth = FirebaseAuth.getInstance();
        budgetRef = FirebaseDatabase.getInstance().getReference().child("budget").child(mAuth.getCurrentUser().getUid());
        loader = new ProgressDialog(this);

        totalBudgetAmountTextView = findViewById(R.id.totalBudgetAmountTextView);
        recyclerView = findViewById(R.id.recyclerView);

        LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this);
        linearLayoutManager.setStackFromEnd(true);
        linearLayoutManager.setReverseLayout(true);
        recyclerView.setHasFixedSize(true);
        recyclerView.setLayoutManager(linearLayoutManager);

        fab = findViewById(R.id.fab);

        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                additem();
            }
        });
    }

    private void additem() {
        AlertDialog.Builder myDialog = new AlertDialog.Builder(this);
        LayoutInflater inflater = LayoutInflater.from(this);
        View myView = inflater.inflate(R.layout.input_layout,null);
        myDialog.setView(myView);

        final AlertDialog dialog =  myDialog.create();
        dialog.setCancelable(false);

        final Spinner itemSpinner = myView.findViewById(R.id.itemSpinner);
        final EditText amount = myView.findViewById(R.id.amount);
        final Button cancel = myView.findViewById(R.id.cancel);
        final  Button save = myView.findViewById(R.id.save);

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

                String budgetAmount = amount.getText().toString();
                String budgetItem = itemSpinner.getSelectedItem().toString();

                if(TextUtils.isEmpty(budgetAmount)){
                    amount.setError("Amount is required!");
                    return;
                }

                if(budgetItem.equals("Select Item")){
                    Toast.makeText(BudgetActivity.this, "Select a valid item", Toast.LENGTH_SHORT).show();
                }else{
                    loader.setMessage("adding a budget item");
                    loader.setCanceledOnTouchOutside(false);
                    loader.show();

                    String id = budgetRef.push().getKey();
                    DateFormat dateFormat = new SimpleDateFormat("dd-MM-yyyy");
                    Calendar cal = Calendar.getInstance();
                    String date = dateFormat.format(cal.getTime());

                    MutableDateTime epoch= new MutableDateTime();
                    epoch.setDate(0);
                    DateTime now = new DateTime();
                    Months months = Months.monthsBetween(epoch,now);

                    Data data = new Data(budgetItem,date,id,null,Integer.parseInt(budgetAmount),months.getMonths());
                    budgetRef.child(id).setValue(data).addOnCompleteListener(new OnCompleteListener<Void>() {
                        @Override
                        public void onComplete(@NonNull Task<Void> task) {
                            if(task.isSuccessful()){
                                Toast.makeText(BudgetActivity.this, "Budget item added successfully.", Toast.LENGTH_SHORT).show();
                            }else{
                                Toast.makeText(BudgetActivity.this, task.getException().toString(), Toast.LENGTH_SHORT).show();
                            }
                            loader.dismiss();
                        }
                    });
                }
                dialog.dismiss();
            }
        });

        cancel.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                dialog.dismiss();
            }
        });


        dialog.show();
    }

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

        FirebaseRecyclerOptions<Data> options = new FirebaseRecyclerOptions.Builder<Data>()
                .setQuery(budgetRef, Data.class)
                .build();
    }
}

2. Below is build.gradle

dependencies {

    implementation 'androidx.appcompat:appcompat:1.5.1'
    implementation 'com.google.android.material:material:1.7.0'
    implementation 'androidx.constraintlayout:constraintlayout:2.1.4'
    implementation 'com.google.firebase:firebase-auth:21.1.0'
    implementation 'com.google.firebase:firebase-database:20.1.0'
    implementation 'com.google.android.material:material:1.7.0'
    implementation 'androidx.cardview:cardview:1.0.0'
    testImplementation 'junit:junit:4.13.2'
    androidTestImplementation 'androidx.test.ext:junit:1.1.4'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.5.0'
    implementation platform('com.google.firebase:firebase-bom:31.1.1')
    implementation 'com.google.firebase:firebase-analytics'
    implementation 'joda-time:joda-time:2.10.6'
    implementation 'com.firebaseui:firebase-ui-database:6.4.0'

}

CodePudding user response：

You're not importing any of the FirebaseUI classes into your Java file yet, so they can't be found.

To be able to use FirebaseRecyclerOptions, include:

import com.firebase.ui.database.FirebaseRecyclerOptions;

You'll need to do the same for other classes from FirebaseUI that you use.