class MediaListBuilder

class MediaListBuilder extends EntityListBuilder {
  
  /**
   * The date formatter service.
   *
   * @var \Drupal\Core\Datetime\DateFormatterInterface
   */
  protected $dateFormatter;
  
  /**
   * The language manager service.
   *
   * @var \Drupal\Core\Language\LanguageManagerInterface
   */
  protected $languageManager;
  
  /**
   * Indicates whether the 'thumbnail' image style exists.
   *
   * @var bool
   */
  protected $thumbnailStyleExists = FALSE;
  
  /**
   * Constructs a new MediaListBuilder object.
   *
   * @param \Drupal\Core\Entity\EntityTypeInterface $entity_type
   *   The entity type definition.
   * @param \Drupal\Core\Entity\EntityStorageInterface $storage
   *   The entity storage class.
   * @param \Drupal\Core\Datetime\DateFormatterInterface $date_formatter
   *   The date formatter service.
   * @param \Drupal\Core\Language\LanguageManagerInterface $language_manager
   *   The language manager service.
   * @param \Drupal\Core\Entity\EntityStorageInterface $image_style_storage
   *   The entity storage class for image styles.
   */
  public function __construct(EntityTypeInterface $entity_type, EntityStorageInterface $storage, DateFormatterInterface $date_formatter, LanguageManagerInterface $language_manager, EntityStorageInterface $image_style_storage) {
    parent::__construct($entity_type, $storage);
    $this->dateFormatter = $date_formatter;
    $this->languageManager = $language_manager;
    $this->thumbnailStyleExists = !empty($image_style_storage->load('thumbnail'));
  }
  
  /**
   * {@inheritdoc}
   */
  public static function createInstance(ContainerInterface $container, EntityTypeInterface $entity_type) {
    $entity_type_manager = $container->get('entity_type.manager');
    return new static($entity_type, $entity_type_manager->getStorage($entity_type->id()), $container->get('date.formatter'), $container->get('language_manager'), $entity_type_manager->getStorage('image_style'));
  }
  
  /**
   * {@inheritdoc}
   */
  public function buildHeader() {
    $header = [];
    if ($this->thumbnailStyleExists) {
      $header['thumbnail'] = [
        'data' => $this->t('Thumbnail'),
        'class' => [
          RESPONSIVE_PRIORITY_LOW,
        ],
      ];
    }
    $header += [
      'name' => $this->t('Media Name'),
      'type' => [
        'data' => $this->t('Type'),
        'class' => [
          RESPONSIVE_PRIORITY_MEDIUM,
        ],
      ],
      'author' => [
        'data' => $this->t('Author'),
        'class' => [
          RESPONSIVE_PRIORITY_LOW,
        ],
      ],
      'status' => $this->t('Status'),
      'changed' => [
        'data' => $this->t('Updated'),
        'class' => [
          RESPONSIVE_PRIORITY_LOW,
        ],
      ],
    ];
    // Enable language column if multiple languages are added.
    if ($this->languageManager
      ->isMultilingual()) {
      $header['language'] = [
        'data' => $this->t('Language'),
        'class' => [
          RESPONSIVE_PRIORITY_LOW,
        ],
      ];
    }
    return $header + parent::buildHeader();
  }
  
  /**
   * {@inheritdoc}
   */
  public function buildRow(EntityInterface $entity) {
    /** @var \Drupal\media\MediaInterface $entity */
    if ($this->thumbnailStyleExists) {
      $row['thumbnail'] = [];
      if ($thumbnail_uri = $entity->getSource()
        ->getMetadata($entity, 'thumbnail_uri')) {
        $row['thumbnail']['data'] = [
          '#theme' => 'image_style',
          '#style_name' => 'thumbnail',
          '#uri' => $thumbnail_uri,
          '#height' => 50,
        ];
      }
    }
    $row['name']['data'] = [
      '#type' => 'link',
      '#title' => $entity->label(),
      '#url' => $entity->toUrl(),
    ];
    $row['type'] = $entity->bundle->entity
      ->label();
    $row['author']['data'] = [
      '#theme' => 'username',
      '#account' => $entity->getOwner(),
    ];
    $row['status'] = $entity->isPublished() ? $this->t('Published') : $this->t('Unpublished');
    $row['changed'] = $this->dateFormatter
      ->format($entity->getChangedTime(), 'short');
    if ($this->languageManager
      ->isMultilingual()) {
      $row['language'] = $this->languageManager
        ->getLanguageName($entity->language()
        ->getId());
    }
    return $row + parent::buildRow($entity);
  }
  
  /**
   * {@inheritdoc}
   */
  protected function getEntityIds() {
    $query = $this->getStorage()
      ->getQuery()
      ->accessCheck(TRUE)
      ->sort('changed', 'DESC');
    // Only add the pager if a limit is specified.
    if ($this->limit) {
      $query->pager($this->limit);
    }
    return $query->execute();
  }

}