voting-postsave.php

<?php

  public function postSave(EntityStorageInterface $storage, $update = TRUE) {
    $rating = $this->get('rating')->first()->value;
    /** @var \Drupal\forkdin_restaurant\Entity\RestaurantMenuItem $menu_item */
    $menu_item = $this->get('menu_item_id')->entity;
    $vote = Vote::create([
      'type' => 'rating',
      'entity_type' => 'checkin',
      'entity_id' => $menu_item->id(),
      'value' => $rating,
      'value_type' => 'points',
      'user_id' => $this->getOwner(),
    ]);
    $vote->save();

    /** @var \Drupal\votingapi\VoteResultFunctionManager $result_function */
    $result_function = \Drupal::service('plugin.manager.votingapi.resultfunction');
    $results = $result_function->getResults('checkin', $menu_item->id());
    $menu_item->setRating($results['rating']['vote_average']);
    $menu_item->save();
  }