private void register(){
    String user = etuser.getText().toString();
    String pass = etPass.getText().toString();
    if(user.isEmpty() && pass.isEmpty()){
        displayToast(getString(R.string.UsuarioVacio));
    } else if (pass.isEmpty()){
        db.addUser(user,"1234","");
        displayToast(getString(R.string.UsuarioExito) +
                getString(R.string.ContraseñaDefecto));
        finish();
    }
    else{
        db.addUser(user,pass,"");
        displayToast(getString(R.string.UsuarioExito2));
        finish();
    }
}