Lab 11 MainActivity.java - reading from Firebase

package com.example.lab11readingdata;

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

import android.os.Bundle;
import android.view.View;
import android.widget.TextView;

import com.google.firebase.FirebaseApp;
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 org.jetbrains.annotations.NotNull;

import java.util.ArrayList;
import java.util.List;

public class MainActivity extends AppCompatActivity {

    private TextView tvData;
    private FirebaseDatabase database;
    private DatabaseReference reference;


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

        tvData = findViewById(R.id.tvData);

        database = FirebaseDatabase.getInstance();
        reference = database.getReference("cars");
    }

    public void onReadSingleClick(View view) {
        reference.child("1").addListenerForSingleValueEvent(
                new ValueEventListener() {
                    @Override
                        public void onDataChange(@NonNull @org.jetbrains.annotations.NotNull DataSnapshot dataSnapshot) {

                            int plate = Integer.parseInt(dataSnapshot.child("plate").getValue().toString());
                            String make = dataSnapshot.child("make").getValue().toString();
                            String model = dataSnapshot.child("model").getValue().toString();
                            int price = Integer.parseInt(dataSnapshot.child("price").getValue().toString());
                            int year = Integer.parseInt(dataSnapshot.child("year").getValue().toString());

                            String details = "Plate: " + plate + "\n" +
                                    "Make : " + make  + "\n" +
                                    "Model: " + model + "\n" +
                                    "Price: " + price + "\n" +
                                    "Year : " + year;

                            tvData.setText(details);

                    }

                        @Override
                        public void onCancelled(@NonNull @org.jetbrains.annotations.NotNull DatabaseError error) {

                        }
                }
        );
    }

    public void onReadAllClick(View view) {
        database.getReference("cars").addValueEventListener(new ValueEventListener() {

            @Override
            public void onDataChange(@NonNull @NotNull DataSnapshot dataSnapshot) {
                List<Car> carList = new ArrayList<>();
                for (DataSnapshot node: dataSnapshot.getChildren()) {
                    Car car = node.getValue(Car.class);
                    carList.add(car);
                }

               updateUI(carList);
            }

            @Override
            public void onCancelled(@NonNull @NotNull DatabaseError error) {

            }
        });
    }

    private void updateUI(List<Car> cars) {
        tvData.setText("");
        for (Car car : cars) {
          tvData.append(car + "\n");
        }
    }
}