@Override
  protected void onActivityResult(int requestCode, int resultCode, Intent data) {

    Bundle params = data.getExtras();
    if (params != null) {
      if (requestCode == CONSTANTE_TELA_1) {

        adapter.add((Evento) data.getSerializableExtra("evento"));
        adapter.notifyDataSetChanged();

      } else if (requestCode == CONSTANTE_TELA_3) {

        meusEventos.set(posicao, (Evento) data.getSerializableExtra("update"));
        adapter.notifyDataSetChanged();
      }
    }
  }
  @Override
  public boolean onContextItemSelected(MenuItem item) {
    if (item.getTitle() == "Atualizar") {

      Intent intent = new Intent(MainActivity.this, UpdateEvento.class);
      String nomeEvento = adapter.getItem(posicao).getNomeEvento().toString();

      intent.putExtra("nomeEvento", nomeEvento);

      startActivityForResult(intent, CONSTANTE_TELA_3);

    } else if (item.getTitle() == "Deletar") {
      meusEventos.remove(posicao);
      adapter.notifyDataSetChanged();
      Toast.makeText(getApplicationContext(), "Excluido", Toast.LENGTH_LONG).show();
    } else {
      return false;
    }
    return true;
  }