/** * Fetches the book link for the next page of the book. * * @param array $book_link * A fully loaded book link that is part of the book hierarchy. * * @return array * A fully loaded book link for the page after the one represented in * $book_link. */ public function nextLink(array $book_link) { // Assigning the array to $flat resets the array pointer for use with each(). $flat = $this->bookManager->bookTreeGetFlat($book_link); do { list($key, ) = each($flat); } while ($key && $key != $book_link['nid']); if ($key == $book_link['nid']) { $next = current($flat); if ($next) { $this->bookManager->bookLinkTranslate($next); } return $next; } }