Firebase data is not displayed

Very good to everyone. I'm trying to load and display the firebase data in a listview hosted in a fragment.

To begin with, I have my Class Bars as follows.

public class Bares {
     String nombre;
     String direccion;
     String foto;

public String getNombre() {
    return nombre;
}

public void setNombre(String nombre) {
    this.nombre = nombre;
}

public String getDireccion() {
    return direccion;
}

public void setDireccion(String direccion) {
    this.direccion = direccion;
}

public String getFoto() {
    return foto;
}

public void setFoto(String foto) {
    this.foto = foto;
}

Adapter Class

public class AdaptadorBares extends ArrayAdapter<Bares> {

public AdaptadorBares(Context context, List<Bares> datos) {
    super(context, R.layout.celda, datos);
}

public View getView(int position, View convertView, ViewGroup parent) {
    // Lead actual.
    Bares bar = getItem(position);
    // ¿Existe el view actual?
    if (convertView == null) {
        convertView = LayoutInflater.from(getContext()).inflate(R.layout.celda, null);
    }
    // Referencias UI.
    TextView lblTitulo = (TextView) convertView.findViewById(R.id.enunciado);
    TextView lblSubtitulo = (TextView) convertView.findViewById(R.id.texto);
    ImageView fotico = (ImageView) convertView.findViewById(R.id.foto);
    // Setup.
    lblTitulo.setText(bar.getNombre());
    lblSubtitulo.setText(bar.getDireccion());
    new DownloadImageTask(fotico).execute(bar.foto);


    return (convertView);
}
private class DownloadImageTask extends AsyncTask<String, Void, Bitmap> {
    ImageView bmImage;

    public DownloadImageTask(ImageView bmImage) {
        this.bmImage = bmImage;
    }

    protected Bitmap doInBackground(String... urls) {
        String urldisplay = urls[0];
        Bitmap mIcon11 = null;
        try {
            InputStream in = new java.net.URL(urldisplay).openStream();
            mIcon11 = BitmapFactory.decodeStream(in);
        } catch (Exception e) {
            Log.e("Error", e.getMessage());
            e.printStackTrace();
        }
        return mIcon11;
    }

    protected void onPostExecute(Bitmap result) {
        bmImage.setImageBitmap(result);
    }
}

Finally I have the fragment where I want to instantiate the adapter and load firebase

 public class BlankFragment extends Fragment {

//FIREBASE
private FirebaseDatabase baseDatos;
private DatabaseReference miBbdd;
//ARRAY
private ArrayList<Bares> bar = new ArrayList<>();
private ArrayAdapter<Bares> adaptadorlista;

ListView lista;


private OnFragmentInteractionListener mListener;

public BlankFragment() {
    // Required empty public constructor
}

// TODO: Rename and change types and number of parameters
public static BlankFragment newInstance(String param1, String param2) {
    BlankFragment fragment = new BlankFragment();
    Bundle args = new Bundle();
    args.putString( ARG_PARAM1, param1 );
    args.putString( ARG_PARAM2, param2 );
    fragment.setArguments( args );
    return fragment;
}

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate( savedInstanceState );
    if (getArguments() != null) {
        mParam1 = getArguments().getString( ARG_PARAM1 );
        mParam2 = getArguments().getString( ARG_PARAM2 );
    }
}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // return inflater.inflate(R.layout.fragment_blank, container, false);
    View view = inflater.inflate( R.layout.fragment_blank, container, false );
    lista = (ListView) view.findViewById( R.id.tvresultado );

    //FirebaseDatabase database = FirebaseDatabase.getInstance().getReferenceFromUrl("https://mapa1-185120.firebaseio.com/Bares");
    // FirebaseDatabase database = FirebaseDatabase.getInstance();
    miBbdd = FirebaseDatabase.getInstance().getReference( "<my-firebase-app>/Bares" );

    adaptadorlista = new ArrayAdapter<Bares>( getActivity(), android.R.layout.simple_list_item_1, bar );
    lista.setAdapter( adaptadorlista );

    miBbdd.addListenerForSingleValueEvent( new ValueEventListener() {
        @Override
        public void onDataChange(DataSnapshot dataSnapshot) {
            bar.clear();
           // for (DataSnapshot snapshot : dataSnapshot.getChildren()) {
                Bares b = new Bares();                     
                b.setNombre( dataSnapshot.getValue( Bares.class ).getNombre() )
                bar.add( b );

            //}
            adaptadorlista.notifyDataSetChanged();
        }

        @Override
        public void onCancelled(DatabaseError databaseError) {

        }
    } );

    return view;
}

// TODO: Rename method, update argument and hook method into UI event
public void onButtonPressed(Uri uri) {
    if (mListener != null) {
        mListener.onFragmentInteraction( uri );
    }
}

@Override
public void onAttach(Context context) {
    super.onAttach( context );
    if (context instanceof OnFragmentInteractionListener) {
        mListener = (OnFragmentInteractionListener) context;
    } else {
        throw new RuntimeException( context.toString()
                + " must implement OnFragmentInteractionListener" );
    }
}

@Override
public void onDetach() {
    super.onDetach();
    mListener = null;
}
public interface OnFragmentInteractionListener {
    // TODO: Update argument type and name
    void onFragmentInteraction(Uri uri);
  }
}

Firebase

What I see in the app

When loading the app shows me what can be seen in the capture, I want to show the data in the table Bars, because later I will have another table called Store that will show something similar to the one of pubs. Greetings and thanks