edlp_d8/core/modules/block_content/src/BlockContentListBuilder.php

<?php

namespace Drupal\block_content;

use Drupal\Core\Entity\EntityInterface;
use Drupal\Core\Entity\EntityListBuilder;

/**
 * Defines a class to build a listing of custom block entities.
 *
 * @see \Drupal\block_content\Entity\BlockContent
 */
class BlockContentListBuilder extends EntityListBuilder {

  /**
   * {@inheritdoc}
   */
  public function buildHeader() {
    $header['label'] = t('Block description');
    return $header + parent::buildHeader();
  }

  /**
   * {@inheritdoc}
   */
  public function buildRow(EntityInterface $entity) {
    $row['label'] = $entity->label();
    return $row + parent::buildRow($entity);
  }

  /**
   * {@inheritdoc}
   */
  protected function getEntityIds() {
    $query = $this->getStorage()->getQuery()
      ->sort($this->entityType->getKey('id'));
    $query->condition('reusable', TRUE);

    // Only add the pager if a limit is specified.
    if ($this->limit) {
      $query->pager($this->limit);
    }
    return $query->execute();
  }

}