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'] = $this->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 = $this->getStorage()
            ->getQuery()
            ->accessCheck(TRUE)
            ->sort($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();
    }

}