require(["gitbook", "jQuery"], function(gitbook, $) { function expand(chapter) { chapter.show(); if (chapter.parent().attr('class') != 'summary' && chapter.parent().attr('class') != 'book-summary' && chapter.length != 0 ) { expand(chapter.parent()); } } gitbook.events.bind("page.change", function() { $('li.chapter').children('ul.articles').hide(); $chapter = $('li.chapter.active'); $children = $chapter.children('ul.articles'); $parent = $chapter.parent(); $siblings = $chapter.siblings().children('ul.articles'); expand($chapter); if ($children.length > 0) { $children.show(); } }); });