class BookBreadcrumbBuilder in Drupal 8

Provides a breadcrumb builder for nodes in a book.

Hierarchy

• class \Drupal\book\BookBreadcrumbBuilder implements BreadcrumbBuilderInterface uses StringTranslationTrait

1 string reference to 'BookBreadcrumbBuilder'

book.services.yml in core/modules/book/book.services.yml

core/modules/book/book.services.yml

1 service uses BookBreadcrumbBuilder

book.breadcrumb in core/modules/book/book.services.yml

Drupal\book\BookBreadcrumbBuilder

File

core/modules/book/src/BookBreadcrumbBuilder.php, line 17

Namespace

Drupal\book

class BookBreadcrumbBuilder implements BreadcrumbBuilderInterface {
  use StringTranslationTrait;

  /**
   * The node storage.
   *
   * @var \Drupal\Core\Entity\EntityStorageInterface
   */
  protected $nodeStorage;

  /**
   * The current user account.
   *
   * @var \Drupal\Core\Session\AccountInterface
   */
  protected $account;

  /**
   * Constructs the BookBreadcrumbBuilder.
   *
   * @param \Drupal\Core\Entity\EntityTypeManagerInterface $entity_type_manager
   *   The entity type manager service.
   * @param \Drupal\Core\Session\AccountInterface $account
   *   The current user account.
   */
  public function __construct(EntityTypeManagerInterface $entity_type_manager, AccountInterface $account) {
    $this->nodeStorage = $entity_type_manager
      ->getStorage('node');
    $this->account = $account;
  }

  /**
   * {@inheritdoc}
   */
  public function applies(RouteMatchInterface $route_match) {
    $node = $route_match
      ->getParameter('node');
    return $node instanceof NodeInterface && !empty($node->book);
  }

  /**
   * {@inheritdoc}
   */
  public function build(RouteMatchInterface $route_match) {
    $book_nids = [];
    $breadcrumb = new Breadcrumb();
    $links = [
      Link::createFromRoute($this
        ->t('Home'), '<front>'),
    ];
    $book = $route_match
      ->getParameter('node')->book;
    $depth = 1;

    // We skip the current node.
    while (!empty($book['p' . ($depth + 1)])) {
      $book_nids[] = $book['p' . $depth];
      $depth++;
    }
    $parent_books = $this->nodeStorage
      ->loadMultiple($book_nids);
    if (count($parent_books) > 0) {
      $depth = 1;
      while (!empty($book['p' . ($depth + 1)])) {
        if (!empty($parent_books[$book['p' . $depth]]) && ($parent_book = $parent_books[$book['p' . $depth]])) {
          $access = $parent_book
            ->access('view', $this->account, TRUE);
          $breadcrumb
            ->addCacheableDependency($access);
          if ($access
            ->isAllowed()) {
            $breadcrumb
              ->addCacheableDependency($parent_book);
            $links[] = Link::createFromRoute($parent_book
              ->label(), 'entity.node.canonical', [
              'node' => $parent_book
                ->id(),
            ]);
          }
        }
        $depth++;
      }
    }
    $breadcrumb
      ->setLinks($links);
    $breadcrumb
      ->addCacheContexts([
      'route.book_navigation',
    ]);
    return $breadcrumb;
  }

}

Members

Name	Modifiers	Type	Description	Overrides
BookBreadcrumbBuilder::$account	protected	property	The current user account.
BookBreadcrumbBuilder::$nodeStorage	protected	property	The node storage.
BookBreadcrumbBuilder::applies	public	function	Whether this breadcrumb builder should be used to build the breadcrumb. Overrides BreadcrumbBuilderInterface::applies
BookBreadcrumbBuilder::build	public	function	Builds the breadcrumb. Overrides BreadcrumbBuilderInterface::build
BookBreadcrumbBuilder::__construct	public	function	Constructs the BookBreadcrumbBuilder.
StringTranslationTrait::$stringTranslation	protected	property	The string translation service.	1
StringTranslationTrait::formatPlural	protected	function	Formats a string containing a count of items.
StringTranslationTrait::getNumberOfPlurals	protected	function	Returns the number of plurals supported by a given language.
StringTranslationTrait::getStringTranslation	protected	function	Gets the string translation service.
StringTranslationTrait::setStringTranslation	public	function	Sets the string translation service to use.	2
StringTranslationTrait::t	protected	function	Translates a string to the current language or to a given language.