diff --git a/core/modules/book/book.module b/core/modules/book/book.module index f9a6ad2..a7313d1 100644 --- a/core/modules/book/book.module +++ b/core/modules/book/book.module @@ -223,10 +223,29 @@ function book_node_load($nodes) { } /** + * Implements hook_entity_extra_field_info(). + */ +function book_entity_extra_field_info() { + $return = array(); + $return['node']['book'] = array( + 'display' => array( + 'book_navigation' => array( + 'label' => t('Book navigation'), + 'description' => t('Book navigation links'), + 'weight' => 100, + 'visible' => TRUE, + ) + ) + ); + + return $return; +} + +/** * Implements hook_ENTITY_TYPE_view() for node entities. */ function book_node_view(array &$build, EntityInterface $node, EntityViewDisplayInterface $display, $view_mode) { - if ($view_mode == 'full') { + if ($display->getComponent('book_navigation')) { if (!empty($node->book['bid']) && empty($node->in_preview)) { $book_node = Node::load($node->book['bid']); if (!$book_node->access()) {