send data from an activity to a java class

since in Android 7.0 nougat the datepicker in spinner mode does not work opt to put the datepicker in a dialog. this is invoked with a button in the activity and executed from a java class and it is sent a return method in which I return the date and set it in the same textView where it was invoked, in a few words I click open the dialog, I select the date I want to accept and set the date in the dialog all right there, my problem is that by clicking the datepicker I get the date today, I found the datepicker.init () method which accepts 4 parameters that are the int of day, month and year, I need to return the data I emptied in the datePicker and send them to this dialog. but I can not do it any help will be very grateful, I can not do the datepicker in another way since it does not work with the spinner in android 7 I leave my code Here it is invoked by clicking on a textView:

Context context;

@Override
protected void onCreate(Bundle savedInstanceState) {
    context = this;
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_index);
    dtbAlert = (TextView) findViewById(R.id.datepickerButtonAlert);
    dtbAlert.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            new CuadroDialog(context, IndexActivity.this);
        }
    });

implements to implements CuadroDialog.finalizaDialogo

JAVA CLASS:

public class CuadroDialog {     public interface finalizesDialog {

    void traerFecha(int dia, int mes, int ano);
}

private finalizaDialogo interfaz;

public CuadroDialog(Context context, finalizaDialogo actividad) {

    interfaz = actividad;
    final Dialog dialog = new Dialog(context);
    dialog.getContext();
    dialog.requestWindowFeature(Window.FEATURE_NO_TITLE);
    dialog.setCancelable(true);
    dialog.setContentView(R.layout.dialog_date_picker);
    final DatePicker datePicker = (DatePicker) dialog.findViewById(R.id.date_datePicker);

    int day = 5; --------> harcode los valores para ver si funcionaba
    int year = 1990;-----> aquí quiero meter el valor del textview 
    int mes = 8;---------> que recuperaria del activity

    datePicker.init(year, day, mes, null);

    TextView btnCancel = (TextView) dialog.findViewById(R.id.botonCancel);
    TextView btnGone = (TextView) dialog.findViewById(R.id.botonGone);

    btnCancel.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            dialog.dismiss();
        }
    });
    btnGone.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            interfaz.traerFecha(datePicker.getDayOfMonth(), datePicker.getMonth() + 1, datePicker.getYear());
            dialog.dismiss();
        }
    });
    dialog.show();
}

}