I can not get return value of the onSuccess method (Uri uri) [closed]

For my college CBT I'm developing an android app. I stopped at a point where I'm downloading the URL of some Firebase Storage images, and within the onSuccess(Uri uri) method, I have access to the uri variable where the URL of the image returns to me so I can switch to Picasso or Glider and download. But the thing is that I can not get this uri value to handle outside of the onSucess() method.

Below is my code:

ListView Locallista;
List<DataProvider> tracks;
DataProvider track;
String uid;
String iid;
Uri bitmap;
View header;
String key;
AdaptadorCuston adaptador;
private FirebaseAuth auth;
Query databaseTracks;
FirebaseDatabase databaseTrack;
FirebaseStorage storage;
StorageReference storageReference;
@Override
protected void onCreate(Bundle savedInstanceState){
    super.onCreate(savedInstanceState);

    setContentView(R.layout.tela_principal);

    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
    toolbar.setTitle("HunterFood Fornecedor");
    setSupportActionBar(toolbar);

    FirebaseUser user = FirebaseAuth.getInstance().getCurrentUser();

    if (user != null) {
        uid = user.getUid();
    }

    auth = FirebaseAuth.getInstance();
    databaseTrack = FirebaseDatabase.getInstance();
    storage = FirebaseStorage.getInstance();

    databaseTracks = 
    databaseTrack.getReference("produtos").orderByChild("id").equalTo(uid);
    storageReference = storage.getReferenceFromUrl("gs://hunterfood-
    a7f41.appspot.com/pictures_prod/");

    tracks = new ArrayList<>();
    Locallista = (ListView) findViewById(R.id.lista);
    header = (View) getLayoutInflater().inflate(R.layout.celula_lista,null);
    Locallista.addHeaderView(header);

    carregarDados();

    Locallista.setOnItemClickListener(new AdapterView.OnItemClickListener(){

        @Override
        public void onItemClick(AdapterView<?> adapterView, View view, int 
    position, long id) {

            Object o = Locallista.getItemAtPosition(position);

            Intent t = new Intent(getApplicationContext(),
            tela_editar.class);
            startActivity(t);
        }
    });
   }

   protected void onStart() {
        super.onStart();
    }

    protected void onResume(){
        super.onResume();
    }

    private void carregarDados() {

        databaseTracks.addValueEventListener(new ValueEventListener(){

        @Override
        public void onDataChange(final DataSnapshot dataSnapshot) {

            tracks.clear();
            for (DataSnapshot postSnapshot : dataSnapshot.getChildren()) {
                track = postSnapshot.getValue(DataProvider.class);
                iid = postSnapshot.getKey();
                track.setKey(iid);

                storageReference.child(iid + 
   ".jpg").getDownloadUrl().addOnSuccessListener(new OnSuccessListener<Uri>
  (){
                    @Override
                    public void onSuccess(Uri uri) {

                        //enter code here
                        bitmap = uri;
                        Context context = getApplicationContext();
                        Toast toast = Toast.makeText(context, "Download Completou", Toast.LENGTH_SHORT);
                        toast.show();
                    }

                }).addOnFailureListener(new OnFailureListener() {

                    @Override
                    public void onFailure(@NonNull Exception exception) {

                        Context context = getApplicationContext();
                        Toast toast = Toast.makeText(context, "Download 
    Falhou", Toast.LENGTH_SHORT);
                        toast.show();
                    }
                });

                track.setIcone(bitmap);
                tracks.add(track);
            }

            adaptador = new 
    AdaptadorCuston(tela_principal.this,R.layout.celula_lista, tracks);

            Locallista.setAdapter(adaptador);
        }

        @Override
        public void onCancelled(DatabaseError databaseError) {
            String mensagem = databaseError.getMessage();
            Toast.makeText(getApplicationContext(), mensagem, 
    Toast.LENGTH_SHORT).show();
        }
    });

Below is the data from the AdapterCuston class:

@NonNull
@Override
public View getView(int position, @Nullable View convertView, @NonNull 
ViewGroup parent) {
    View row;
    row = convertView;
    DataHandler handler;
    if(convertView == null){
       LayoutInflater inflater =


  (LayoutInflater)this.getContext().getSystemService(
   Context.LAYOUT_INFLATER_SERVICE);
        row = inflater.inflate(R.layout.celula_lista,parent, false);
        handler = new DataHandler();
        handler.imagemIcone = (ImageView)row.findViewById(R.id.img_lista);
        handler.titulo = (TextView) row.findViewById(R.id.txt_titulo);
        handler.descricao = (TextView) row.findViewById(R.id.txt_descricao);
        row.setTag(handler);
    }else{
        handler = (DataHandler)row.getTag();
    }
    DataProvider dataProvider;
    dataProvider = (DataProvider) this.getItem(position);
    Glide
            .with(getContext())
            .load(dataProvider.getIcone())
            .into(handler.imagemIcone); 
    handler.titulo.setText(dataProvider.getTitulo());
    handler.descricao.setText(dataProvider.getDescricao());
    return row;
}
    private class DataHandler {
        ImageView imagemIcone;
        TextView titulo;
        TextView descricao;
    }
}