/** * {@inheritdoc} */ public function validateForm(array &$form, FormStateInterface $form_state) { parent::validateForm($form, $form_state); $embed_provider = $form_state->getValue('embed_provider'); $this->prepareEmbedProviderValidation($embed_provider); if (!URLHelper::isValid($embed_provider, TRUE)) { $form_state->setErrorByName('embed_provider', $this->t('The provider url was not valid.')); } }