/**
  * Performs an operation on the payment method entity.
  *
  * @param \Drupal\uc_payment\PaymentMethodInterface $uc_payment_method
  *   The payment method entity.
  * @param string $op
  *   The operation to perform, usually 'enable' or 'disable'.
  *
  * @return \Symfony\Component\HttpFoundation\RedirectResponse
  *   A redirect back to the payment method listing page.
  */
 public function performOperation(PaymentMethodInterface $uc_payment_method, $op)
 {
     $uc_payment_method->{$op}()->save();
     if ($op == 'enable') {
         drupal_set_message($this->t('The %label payment method has been enabled.', ['%label' => $uc_payment_method->label()]));
     } elseif ($op == 'disable') {
         drupal_set_message($this->t('The %label payment method has been disabled.', ['%label' => $uc_payment_method->label()]));
     }
     $url = $uc_payment_method->toUrl('collection');
     return $this->redirect($url->getRouteName(), $url->getRouteParameters(), $url->getOptions());
 }
 /**
  * {@inheritdoc}
  */
 public function save(array $form, FormStateInterface $form_state)
 {
     $this->entity->save();
     drupal_set_message($this->t('Saved the %label payment method.', ['%label' => $this->entity->label()]));
     $form_state->setRedirectUrl($this->entity->toUrl('collection'));
 }