public function BookNavigationBlock::build

Builds and returns the renderable array for this block plugin.

Return value

array A renderable array representing the content of the block.

Overrides BlockPluginInterface::build

See also

\Drupal\block\BlockRenderController

File

drupal/core/modules/book/lib/Drupal/book/Plugin/Block/BookNavigationBlock.php, line 64

Contains \Drupal\book\Plugin\Block\BookNavigationBlock.

Class

BookNavigationBlock

Provides a 'Book navigation' block.

Namespace

Code

public function build() {
  $current_bid = 0;
  if ($node = menu_get_object()) {
    $current_bid = empty($node->book['bid']) ? 0 : $node->book['bid'];
  }
  if ($this->configuration['block_mode'] == 'all pages') {
    $book_menus = array();
    $pseudo_tree = array(
      0 => array(
        'below' => FALSE,
      ),
    );
    foreach (book_get_books() as $book_id => $book) {
      if ($book['bid'] == $current_bid) {

        // If the current page is a node associated with a book, the menu
        // needs to be retrieved.
        $book_menus[$book_id] = menu_tree_output(menu_tree_all_data($node->book['menu_name'], $node->book));
      }
      else {

        // Since we know we will only display a link to the top node, there
        // is no reason to run an additional menu tree query for each book.
        $book['in_active_trail'] = FALSE;

        // Check whether user can access the book link.
        $book_node = node_load($book['nid']);
        $book['access'] = node_access('view', $book_node);
        $pseudo_tree[0]['link'] = $book;
        $book_menus[$book_id] = menu_tree_output($pseudo_tree);
      }
    }
    if ($book_menus) {
      return array(
        '#theme' => 'book_all_books_block',
        $book_menus,
      );
    }
  }
  elseif ($current_bid) {

    // Only display this block when the user is browsing a book.
    $select = db_select('node', 'n')
      ->fields('n', array(
      'nid',
    ))
      ->condition('n.nid', $node->book['bid'])
      ->addTag('node_access');
    $nid = $select
      ->execute()
      ->fetchField();

    // Only show the block if the user has view access for the top-level node.
    if ($nid) {
      $tree = menu_tree_all_data($node->book['menu_name'], $node->book);

      // There should only be one element at the top level.
      $data = array_shift($tree);
      $below = menu_tree_output($data['below']);
      if (!empty($below)) {
        $book_title_link = array(
          '#theme' => 'book_title_link',
          '#link' => $data['link'],
        );
        return array(
          '#title' => drupal_render($book_title_link),
          $below,
        );
      }
    }
  }
  return array();
}