ListingEmpty.php

<?php

namespace Drupal\block_content\Plugin\views\area;

use Drupal\Core\Access\AccessManagerInterface;
use Drupal\Core\Session\AccountInterface;
use Drupal\Core\Url;
use Drupal\views\Plugin\views\area\AreaPluginBase;
use Symfony\Component\DependencyInjection\ContainerInterface;

/**
 * Defines an area plugin to display a block add link.
 *
 * @ingroup views_area_handlers
 *
 * @ViewsArea("block_content_listing_empty")
 */
class ListingEmpty extends AreaPluginBase {
    
    /**
     * The access manager.
     *
     * @var \Drupal\Core\Access\AccessManagerInterface
     */
    protected $accessManager;
    
    /**
     * The current user.
     *
     * @var \Drupal\Core\Session\AccountInterface
     */
    protected $currentUser;
    
    /**
     * Constructs a new ListingEmpty.
     *
     * @param array $configuration
     *   A configuration array containing information about the plugin instance.
     * @param string $plugin_id
     *   The plugin ID for the plugin instance.
     * @param mixed $plugin_definition
     *   The plugin implementation definition.
     * @param \Drupal\Core\Access\AccessManagerInterface $access_manager
     *   The access manager.
     * @param \Drupal\Core\Session\AccountInterface $current_user
     *   The current user.
     */
    public function __construct(array $configuration, $plugin_id, $plugin_definition, AccessManagerInterface $access_manager, AccountInterface $current_user) {
        parent::__construct($configuration, $plugin_id, $plugin_definition);
        $this->accessManager = $access_manager;
        $this->currentUser = $current_user;
    }
    
    /**
     * {@inheritdoc}
     */
    public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
        return new static($configuration, $plugin_id, $plugin_definition, $container->get('access_manager'), $container->get('current_user'));
    }
    
    /**
     * {@inheritdoc}
     */
    public function render($empty = FALSE) {
        if (!$empty || !empty($this->options['empty'])) {
            
            /** @var \Drupal\Core\Access\AccessResultInterface|\Drupal\Core\Cache\CacheableDependencyInterface $access_result */
            $access_result = $this->accessManager
                ->checkNamedRoute('block_content.add_page', [], $this->currentUser, TRUE);
            $element = [
                '#markup' => $this->t('Add a <a href=":url">custom block</a>.', [
                    ':url' => Url::fromRoute('block_content.add_page')->toString(),
                ]),
                '#access' => $access_result->isAllowed(),
                '#cache' => [
                    'contexts' => $access_result->getCacheContexts(),
                    'tags' => $access_result->getCacheTags(),
                    'max-age' => $access_result->getCacheMaxAge(),
                ],
            ];
            return $element;
        }
        return [];
    }

}