How to Handle classes in a Thread within a Service

Question

I am having a problem related to a Thread. I need to use 2 classes that are outside of it and is giving me the following error:

E/Androidruntime: FATAL EXCEPTION: Thread-3 Process: com.example.Safeway, PID: 8681 java.lang.Illegalstateexception: Can’t create Handler Inside thread that has not called Looper.prepare() at com.google.android.gms.common.internal.Preconditions.checkstate(Unknown Source:29) at com.google.android.gms.Internal.location.zzbm.zzc(Unknown Source:11) at com.google.android.gms.Internal.location.zzbm.zza(Unknown Source:3) at com.google.android.gms.Location.FusedLocationProviderClient.requestLocationUpdates(Unknown Source:4) at.example.Safeway.Mapservice$Checker.run(Mapservice.java:91)

The classes are: buildLocationRequest and buildLocationCallBack, but I don’t know how to make them work inside the thread, I saw that it was with Handlers but I couldn’t find anything that would really help me. I wanted to take advantage of the post to ask if when I deal with Handles I will be able to make a Real-Time database using Firebase to update the longitude and latitude of a specific user? Because I tried several other methods to do it within a service and until now I did not succeed.

public class MapService extends Service{
FirebaseDatabase bancoDeDados;
DatabaseReference usuarioBancoDeDados;


FusedLocationProviderClient fusedLocationProviderClient;
LocationRequest locationRequest;
LocationCallback locationCallback;

//Cria uma lista de threads para fazer a manutenção
public List<Verificador> threads = new ArrayList<Verificador>();

@Nullable
@Override
public IBinder onBind(Intent intent) {
    return null;
}

//Criou, chama apenas 1 vez
@Override
public void onCreate() {
    super.onCreate();
}

// Será repetido diversas vezes
public int onStartCommand(Intent intent, int flag, int startID) {
    Verificador verificador = new Verificador(startID);
    verificador.start();
    threads.add(verificador);

    return (START_STICKY); // usar START_REDELIVER_INTENT caso o intent seja necessário o reenvio
}


class Verificador extends Thread {  
    public int startID;
    boolean ativo = true;

    public Verificador(int startID) {
        this.startID = startID;
    }

    @SuppressLint("MissingPermission")
    public void run() {
        while (ativo) {
            //Longitude/Latitude
            buildLocationRequest();
            buildLocationCallBack();
            fusedLocationProviderClient = LocationServices.getFusedLocationProviderClient(MapService.this);
            fusedLocationProviderClient.requestLocationUpdates(locationRequest,locationCallback,Looper.myLooper());


        }
        stopSelf();
    }
}

private void buildLocationRequest(){
    Log.i("Debug","LOCATION REQUEST");
    locationRequest = new LocationRequest();
    locationRequest.setPriority(locationRequest.PRIORITY_HIGH_ACCURACY);
    locationRequest.setInterval(5000);
    locationRequest.setFastestInterval(3000);
    locationRequest.setSmallestDisplacement(10);

}

private void buildLocationCallBack(){
    locationCallback = new LocationCallback(){
        @Override
        public void onLocationResult(LocationResult locationResult) {
            for (Location location:locationResult.getLocations()){
                usuarioBancoDeDados = bancoDeDados.getReference("Usuários");
                usuarioBancoDeDados.child("Usuários").child(usuarioAtual.getNomeUsuario()).child("latitudeUsuario").setValue(location.getLatitude());
                usuarioBancoDeDados.child("Usuários").child(usuarioAtual.getNomeUsuario()).child("longitudeUsuario").setValue(location.getLongitude());
            }
        }
    };
}

//mata a tread
@Override
public void onDestroy() {
    super.onDestroy();
    Log.i("Debug","CABO");
    for (int i = 0, tam = threads.size(); i < tam; i++){
        threads.get(i).ativo = false;
    }
}

}