/**
  * {@inheritdoc}
  */
 public function submitForm(array &$form, FormStateInterface $form_state)
 {
     /** @var \Drupal\search_api\ServerInterface $server */
     $server = $this->getEntity();
     try {
         $server->deleteAllItems();
         drupal_set_message($this->t('All indexed data was successfully deleted from the server.'));
     } catch (SearchApiException $e) {
         drupal_set_message($this->t('Indexed data could not be cleared for some indexes. Check the logs for details.'), 'error');
     }
     $failed_reindexing = array();
     $properties = array('status' => TRUE, 'read_only' => FALSE);
     foreach ($server->getIndexes($properties) as $index) {
         try {
             $index->reindex();
         } catch (SearchApiException $e) {
             $args = array('%index' => $index->label());
             watchdog_exception('search_api', $e, '%type while clearing index %index: @message in %function (line %line of %file).', $args);
             $failed_reindexing[] = $index->label();
         }
     }
     if ($failed_reindexing) {
         $args = array('@indexes' => implode(', ', $failed_reindexing));
         drupal_set_message($this->t('Failed to mark the following indexes for reindexing: @indexes. Check the logs for details.', $args), 'warning');
     }
     $form_state->setRedirect('entity.search_api_server.canonical', array('search_api_server' => $server->id()));
 }

 /**
  * {@inheritdoc}
  */
 public function submit(array $form, FormStateInterface $form_state)
 {
     $this->entity->delete();
     drupal_set_message($this->t('Responsive image mapping %label has been deleted.', array('%label' => $this->entity->label())));
     $this->logger('responsive_image')->notice('Responsive image mapping %label has been deleted.', array('%label' => $this->entity->label()));
     $form_state->setRedirectUrl($this->getCancelUrl());
 }

 /**
  * {@inheritdoc}
  */
 public function submitForm(array &$form, FormStateInterface $form_state)
 {
     $settings = array('types' => $form_state->getValue('types'));
     $this->currentBundle->setAssignmentSettings(self::METHOD_ID, $settings)->save();
     $this->setRedirect($form_state);
     drupal_set_message($this->t('Package assignment configuration saved.'));
 }

 /**
  * {@inheritdoc}
  */
 public function submitForm(array &$form, FormStateInterface $form_state)
 {
     $this->taxonomyTerm->delete();
     drupal_set_message($this->t('The forum %label and all sub-forums have been deleted.', array('%label' => $this->taxonomyTerm->label())));
     $this->logger('forum')->notice('forum: deleted %label and all its sub-forums.', array('%label' => $this->taxonomyTerm->label()));
     $form_state->setRedirectUrl($this->getCancelUrl());
 }

 public function validateExposed(&$form, FormStateInterface $form_state)
 {
     if (empty($this->options['exposed'])) {
         return;
     }
     if (empty($this->options['expose']['identifier'])) {
         return;
     }
     $identifier = $this->options['expose']['identifier'];
     $input = $form_state->getValue($identifier);
     if ($this->options['is_grouped'] && isset($this->options['group_info']['group_items'][$input])) {
         $this->operator = $this->options['group_info']['group_items'][$input]['operator'];
         $input = $this->options['group_info']['group_items'][$input]['value'];
     }
     $uids = [];
     $values = $form_state->getValue($identifier);
     if ($values && (!$this->options['is_grouped'] || $this->options['is_grouped'] && $input != 'All')) {
         foreach ($values as $value) {
             $uids[] = $value['target_id'];
         }
     }
     if ($uids) {
         $this->validated_exposed_input = $uids;
     }
 }

 /**
  * Form validation handler for widget elements.
  *
  * @param array $element
  *   The form element.
  * @param \Drupal\Core\Form\FormStateInterface $form_state
  *   The form state.
  */
 public static function validateElement(array $element, FormStateInterface $form_state)
 {
     if ($element['#required'] && $element['#value'] == '_none') {
         $form_state->setError($element, t('@name field is required.', array('@name' => $element['#title'])));
     }
     // Massage submitted form values.
     // Drupal\Core\Field\WidgetBase::submit() expects values as
     // an array of values keyed by delta first, then by column, while our
     // widgets return the opposite.
     if (is_array($element['#value'])) {
         $values = array_values($element['#value']);
     } else {
         $values = array($element['#value']);
     }
     // Filter out the 'none' option. Use a strict comparison, because
     // 0 == 'any string'.
     $index = array_search('_none', $values, TRUE);
     if ($index !== FALSE) {
         unset($values[$index]);
     }
     // Transpose selections from field => delta to delta => field.
     $items = array();
     foreach ($values as $value) {
         $items[] = array($element['#key_column'] => $value);
     }
     $form_state->setValueForElement($element, $items);
 }

 /**
  * {@inheritdoc}
  */
 public function submit(array &$element, array &$form, FormStateInterface $form_state)
 {
     $media_entities = [];
     $upload = $form_state->getValue('upload');
     if (isset($upload['uploaded_files']) && is_array($upload['uploaded_files'])) {
         $config = $this->getConfiguration();
         $user = $this->currentUser;
         /** @var \Drupal\media_entity\MediaBundleInterface $bundle */
         $bundle = $this->entityManager->getStorage('media_bundle')->load($this->configuration['media_entity_bundle']);
         // First save the file.
         foreach ($upload['uploaded_files'] as $uploaded_file) {
             $file = $this->dropzoneJsUploadSave->saveFile($uploaded_file['path'], $config['settings']['upload_location'], $config['settings']['extensions'], $user);
             if ($file) {
                 $file->setPermanent();
                 $file->save();
                 // Now save the media entity.
                 if ($this->moduleHandler->moduleExists('media_entity')) {
                     /** @var \Drupal\media_entity\MediaInterface $media_entity */
                     $media_entity = $this->entityManager->getStorage('media')->create(['bundle' => $bundle->id(), $bundle->getTypeConfiguration()['source_field'] => $file, 'uid' => $user->id(), 'status' => TRUE, 'type' => $bundle->getType()->getPluginId()]);
                     $event = $this->eventDispatcher->dispatch(Events::MEDIA_ENTITY_CREATE, new DropzoneMediaEntityCreateEvent($media_entity, $file, $form, $form_state, $element));
                     $media_entity = $event->getMediaEntity();
                     $media_entity->save();
                     $media_entities[] = $media_entity;
                 } else {
                     drupal_set_message(t('The media entity was not saved, because the media_entity module is not enabled.'));
                 }
             }
         }
     }
     if (!empty(array_filter($media_entities))) {
         $this->selectEntities($media_entities, $form_state);
         $this->clearFormValues($element, $form_state);
     }
 }

 /**
  * {@inheritdoc}
  */
 public function submitForm(array &$form, FormStateInterface $form_state)
 {
     /** @var \Drupal\payment\Plugin\Payment\LineItem\PaymentLineItemInterface $line_item */
     $line_item = $form_state->get('payment_line_item');
     $line_item->submitConfigurationForm($form['line_item'], $form_state);
     $form_state->setRedirect('user.login');
 }

 public function submitOptionsForm(&$form, FormStateInterface $form_state)
 {
     $exposed_form_options = $form_state->getValue('exposed_form_options');
     $form_state->setValue(array('exposed_form_options', 'text_input_required_format'), $exposed_form_options['text_input_required']['format']);
     $form_state->setValue(array('exposed_form_options', 'text_input_required'), $exposed_form_options['text_input_required']['value']);
     parent::submitOptionsForm($form, $form_state);
 }

 /**
  * {@inheritdoc}
  */
 public function buildForm(array $form, FormStateInterface $form_state, LanguageInterface $language = NULL)
 {
     if ($language) {
         $form_state->set('langcode', $language->getId());
     }
     return parent::buildForm($form, $form_state);
 }

 /**
  * {@inheritdoc}
  */
 public function submitForm(array &$form, FormStateInterface $form_state)
 {
     drupal_set_message($this->t('The static context %label has been removed.', ['%label' => $this->page->getStaticContext($this->staticContext)['label']]));
     $this->page->removeStaticContext($this->staticContext);
     $this->page->save();
     $form_state->setRedirectUrl($this->getCancelUrl());
 }

 /**
  * {@inheritdoc}
  */
 public function submit(array $form, FormStateInterface $form_state)
 {
     $this->entity->delete();
     drupal_set_message($this->t('Custom block %label has been deleted.', array('%label' => $this->entity->label())));
     $this->logger('block_content')->notice('Custom block %label has been deleted.', array('%label' => $this->entity->label()));
     $form_state->setRedirect('block_content.list');
 }

 /**
  * {@inheritdoc}
  */
 public function formElement(FieldItemListInterface $items, $delta, array $element, array &$form, FormStateInterface $form_state)
 {
     /* @var $instance \Drupal\mailchimp_lists\Plugin\Field\FieldType\MailchimpListsSubscription */
     $instance = $items[0];
     $subscribe_default = $instance->getSubscribe();
     $email = NULL;
     if (!empty($instance->getEntity())) {
         $email = mailchimp_lists_load_email($instance, $instance->getEntity(), FALSE);
         if ($email) {
             $subscribe_default = mailchimp_is_subscribed($instance->getFieldDefinition()->getSetting('mc_list_id'), $email);
         }
     }
     $element += array('#title' => SafeMarkup::checkPlain($element['#title']), '#type' => 'fieldset');
     $element['subscribe'] = array('#title' => t('Subscribe'), '#type' => 'checkbox', '#default_value' => $subscribe_default ? TRUE : $this->fieldDefinition->isRequired(), '#required' => $this->fieldDefinition->isRequired(), '#disabled' => $this->fieldDefinition->isRequired());
     $form_id = $form_state->getFormObject()->getFormId();
     if ($this->fieldDefinition->getSetting('show_interest_groups') || $form_id == 'field_ui_field_edit_form') {
         $mc_list = mailchimp_get_list($instance->getFieldDefinition()->getSetting('mc_list_id'));
         $element['interest_groups'] = array('#type' => 'fieldset', '#title' => SafeMarkup::checkPlain($instance->getFieldDefinition()->getSetting('interest_groups_title')), '#weight' => 100, '#states' => array('invisible' => array(':input[name="' . $instance->getFieldDefinition()->getName() . '[0][value][subscribe]"]' => array('checked' => FALSE))));
         if ($form_id == 'field_ui_field_edit_form') {
             $element['interest_groups']['#states']['invisible'] = array(':input[name="field[settings][show_interest_groups]"]' => array('checked' => FALSE));
         }
         $groups_default = $instance->getInterestGroups();
         if ($groups_default == NULL) {
             $groups_default = array();
         }
         if ($mc_list['stats']['group_count']) {
             $element['interest_groups'] += mailchimp_interest_groups_form_elements($mc_list, $groups_default, $email);
         }
     }
     return array('value' => $element);
 }

 /**
  * {@inheritdoc}
  */
 public function finish(array &$form, FormStateInterface $form_state)
 {
     $cached_values = $form_state->getTemporaryValue('wizard');
     drupal_set_message($this->t('Value One: @one', ['@one' => $cached_values['one']]));
     drupal_set_message($this->t('Value Two: @two', ['@two' => $cached_values['two']]));
     parent::finish($form, $form_state);
 }

 /**
  * Form element validation handler for matched_path elements.
  *
  * Note that #maxlength is validated by _form_validate() already.
  *
  * This checks that the submitted value matches an active route.
  */
 public static function validateMatchedPath(&$element, FormStateInterface $form_state, &$complete_form)
 {
     if (!empty($element['#value']) && ($element['#validate_path'] || $element['#convert_path'] != self::CONVERT_NONE)) {
         /** @var \Drupal\Core\Url $url */
         if ($url = \Drupal::service('path.validator')->getUrlIfValid($element['#value'])) {
             if ($url->isExternal()) {
                 $form_state->setError($element, t('You cannot use an external URL, please enter a relative path.'));
                 return;
             }
             if ($element['#convert_path'] == self::CONVERT_NONE) {
                 // Url is valid, no conversion required.
                 return;
             }
             // We do the value conversion here whilst the Url object is in scope
             // after validation has occurred.
             if ($element['#convert_path'] == self::CONVERT_ROUTE) {
                 $form_state->setValueForElement($element, array('route_name' => $url->getRouteName(), 'route_parameters' => $url->getRouteParameters()));
                 return;
             } elseif ($element['#convert_path'] == self::CONVERT_URL) {
                 $form_state->setValueForElement($element, $url);
                 return;
             }
         }
         $form_state->setError($element, t('This path does not exist or you do not have permission to link to %path.', array('%path' => $element['#value'])));
     }
 }

 /**
  * Form submission handler.
  *
  * @param array $form
  *   An associative array containing the structure of the form.
  * @param \Drupal\Core\Form\FormStateInterface $form_state
  *   The current state of the form.
  */
 public function submitForm(array &$form, FormStateInterface $form_state)
 {
     $author = $form_state->getValue('author');
     $body = $form_state->getValue('body');
     $title = $form_state->getValue('title');
     drupal_set_message('Thanks for submitting the form! you typed in the following as author:' . $author . ' . body:' . $body . '. title:' . $title);
 }

 public function submitForm(array &$form, \Drupal\Core\Form\FormStateInterface $form_state)
 {
     // Check to make sure that the file was uploaded to the server properly
     $userInputValues = $form_state->getUserInput();
     $uri = db_select('file_managed', 'f')->condition('f.fid', $userInputValues['import']['fids'], '=')->fields('f', array('uri'))->execute()->fetchField();
     if (!empty($uri)) {
         if (file_exists(\Drupal::service("file_system")->realpath($uri))) {
             // Open the csv
             $handle = fopen(\Drupal::service("file_system")->realpath($uri), "r");
             // Go through each row in the csv and run a function on it. In this case we are parsing by '|' (pipe) characters.
             // If you want commas are any other character, replace the pipe with it.
             while (($data = fgetcsv($handle, 0, ',', '"')) !== FALSE) {
                 $operations[] = ['csvimport_import_batch_processing', [$data]];
             }
             // Once everything is gathered and ready to be processed... well... process it!
             $batch = ['title' => t('Importing CSV...'), 'operations' => $operations, 'finished' => $this->csvimport_import_finished(), 'error_message' => t('The installation has encountered an error.'), 'progress_message' => t('Imported @current of @total products.')];
             batch_set($batch);
             fclose($handle);
         } else {
             drupal_set_message(t('Not able to find file path.'), 'error');
         }
     } else {
         drupal_set_message(t('There was an error uploading your file. Please contact a System administator.'), 'error');
     }
 }

 /**
  * {@inheritdoc}
  */
 public function submitForm(array &$form, FormStateInterface $form_state)
 {
     $values = $form_state->getValues();
     $file = File::load($values['file'][0]);
     // Load File entity.
     $read_file = new \SplFileObject($file->url());
     // Create file handler.
     $lines = 1;
     $in_queue = 0;
     $queue = \Drupal::queue('eventninja');
     // Load queue
     while (!$read_file->eof()) {
         $data = $read_file->fgetcsv(';');
         if ($lines > 1) {
             // skip headers
             $user = user_load_by_mail($data[1]);
             if ($user === false) {
                 // Verify if user with specified email does not exist.
                 $queue->createItem($data);
                 $in_queue++;
             } else {
                 $this->logger('eventninja')->log(RfcLogLevel::NOTICE, 'User {mail} hasn\'t been created.', ['mail' => $data[1]]);
             }
         }
         $lines++;
     }
     if ($lines > 1) {
         drupal_set_message($this->t('@num records was scheduled for import', array('@num' => $in_queue)), 'success');
     } else {
         drupal_set_message($this->t('File contains only headers'), 'error');
     }
 }

 /**
  * {@inheritdoc}
  */
 public static function value(array &$element, &$input, FormStateInterface $form_state)
 {
     if (isset($input['filefield_reference']['autocomplete']) && strlen($input['filefield_reference']['autocomplete']) > 0 && $input['filefield_reference']['autocomplete'] != FILEFIELD_SOURCE_REFERENCE_HINT_TEXT) {
         $matches = array();
         if (preg_match('/\\[fid:(\\d+)\\]/', $input['filefield_reference']['autocomplete'], $matches)) {
             $fid = $matches[1];
             if ($file = file_load($fid)) {
                 // Remove file size restrictions, since the file already exists on
                 // disk.
                 if (isset($element['#upload_validators']['file_validate_size'])) {
                     unset($element['#upload_validators']['file_validate_size']);
                 }
                 // Check that the user has access to this file through
                 // hook_download().
                 if (!$file->access('download')) {
                     $form_state->setError($element, t('You do not have permission to use the selected file.'));
                 } elseif (filefield_sources_element_validate($element, (object) $file, $form_state)) {
                     if (!in_array($file->id(), $input['fids'])) {
                         $input['fids'][] = $file->id();
                     }
                 }
             } else {
                 $form_state->setError($element, t('The referenced file could not be used because the file does not exist in the database.'));
             }
         }
         // No matter what happens, clear the value from the autocomplete.
         $input['filefield_reference']['autocomplete'] = '';
     }
 }

 /**
  * {@inheritdoc}
  */
 public function save(array $form, FormStateInterface $form_state)
 {
     try {
         $entity = $this->entity;
         // Save as a new revision if requested to do so.
         if (!$form_state->isValueEmpty('revision')) {
             $entity->setNewRevision();
         }
         $is_new = $entity->isNew();
         $entity->save();
         if ($is_new) {
             $message = t('%entity_type @id has been created.', array('@id' => $entity->id(), '%entity_type' => $entity->getEntityTypeId()));
         } else {
             $message = t('%entity_type @id has been updated.', array('@id' => $entity->id(), '%entity_type' => $entity->getEntityTypeId()));
         }
         drupal_set_message($message);
         if ($entity->id()) {
             $entity_type = $entity->getEntityTypeId();
             $form_state->setRedirect("entity.{$entity_type}.edit_form", array($entity_type => $entity->id()));
         } else {
             // Error on save.
             drupal_set_message(t('The entity could not be saved.'), 'error');
             $form_state->setRebuild();
         }
     } catch (\Exception $e) {
         \Drupal::state()->set('entity_test.form.save.exception', get_class($e) . ': ' . $e->getMessage());
     }
 }