ViewPageController.php

<?php

/**
 * @file
 * Contains \Drupal\views\Routing\ViewPageController.
 */
namespace Drupal\views\Routing;

use Drupal\Core\Controller\ControllerInterface;
use Drupal\Core\Entity\EntityStorageControllerInterface;
use Drupal\views\ViewExecutableFactory;
use Symfony\Component\DependencyInjection\ContainerInterface;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;

/**
 * Defines a page controller to execute and render a view.
 */
class ViewPageController implements ControllerInterface {

  /**
   * The entity storage controller.
   *
   * @var \Drupal\Core\Entity\EntityStorageControllerInterface
   */
  protected $storageController;

  /**
   * The view executable factory.
   *
   * @var \Drupal\views\ViewExecutableFactory
   */
  protected $executableFactory;

  /**
   * Constructs a ViewPageController object.
   *
   * @param \Drupal\Core\Entity\EntityStorageControllerInterface $storage_controller
   *   The entity storage controller.
   * @param \Drupal\views\ViewExecutableFactory $executable_factory
   *   The view executable factory
   */
  public function __construct(EntityStorageControllerInterface $storage_controller, ViewExecutableFactory $executable_factory) {
    $this->storageController = $storage_controller;
    $this->executableFactory = $executable_factory;
  }

  /**
   * {@inheritdoc}
   */
  public static function create(ContainerInterface $container) {
    return new static($container
      ->get('plugin.manager.entity')
      ->getStorageController('view'), $container
      ->get('views.executable'));
  }

  /**
   * Handles a response for a view.
   */
  public function handle(Request $request) {
    $view_id = $request->attributes
      ->get('view_id');
    $display_id = $request->attributes
      ->get('display_id');
    $entities = $this->storageController
      ->load(array(
      $view_id,
    ));
    $entity = reset($entities);
    if (empty($entity)) {
      throw new NotFoundHttpException(format_string('Page controller for view %id requested, but view was not found.', array(
        '%id' => $view_id,
      )));
    }
    $view = $this->executableFactory
      ->get($entity);
    $view
      ->setDisplay($display_id);
    $view
      ->initHandlers();
    $args = array();
    foreach (array_keys((array) $view->argument) as $argument_id) {
      $arg = $request->attributes
        ->get('arg_' . $argument_id);
      if (isset($arg)) {
        $args[] = $arg;
      }
    }
    return $view
      ->executeDisplay($display_id, $args);
  }

}