So, I have a navigation that is a list and has sublists and sublists.
Basically, the nav is by default collapsed, but if people click on a page that's in a sublist, I want to show the parent list. And if it's a sublist of a sublist, I need both parent lists to show. I have it set up, but, I don't like putting 5 .parent().parent() 's to traverse upward to expand the list. Is there a more efficient way?
the HTML:
<div id="lesson-sidebar">
<ul>
<li><a href="index.html">Welcome to Beat Basics and Beyond</a></li>
<li><a href="table-of-contents.html">What's in this course?</a></li>
<li><a href="defining-your-beat.html" class="active">Defining Your Beat</a>
<ul>
<li><a href="boundaries-of-your-beat.html">Boundaries of Your Beat</a></li>
<li><a href="the-beat-description.html">The Beat Description</a></li>
<li><a href="build-your-own-beat-description.html"><span class="ital">Activity:</span> Build Your Own Beat Description</a></li>
</ul>
</li>
<li><a href="getting-started.html">Getting Started</a>
<ul>
<li><a href="debrief-your-predecessor.html">Debrief Your Predecessor</a></li>
<li><a href="predecessor-top-five-tips.html"><span class="ital">Activity:</span> List The Top Five Tips From Your Predecessor</a></li>
<li><a href="covering-your-beat-with-the-internet.html">Covering Your Beat With The Internet</a></li>
<li><a href="get-in-the-car-and-go.html">Get in the Car and Go</a></li>
<li><a href="mapping-your-beat.html">Mapping Your Beat</a></li>
<li><a href="read-the-clips.html">Read the Clips</a></li>
<li><a href="activity-dissect-this-clip.html"><span class="ital">Activity:</span> Dissect This Clip</a></li>
<li><a href="writing-your-first-article.html">Writing Your First Article</a></li>
<li><a href="starting-cold-on-the-beat.html">Starting Cold on the Beat</a></li>
</ul>
</li>
<li><a href="working-with-sources.html">Working With Sources</a>
<ul>
<li><a href="finding-sources.html">Finding Sources</a></li>
<li><a href="diversify-your-sources.html">Diversify Your Sources</a></li>
<li><a href="prospecting-for-stories-and-sources.html">Prospecting for Stories and Sources</a></li>
<li><a href="building-relationships.html">Building Relationships</a></li>
<li><a href="going-off-the-record.html">Going Off the Record</a></li>
</ul>
</li>
<li><a href="developing-resources.html">Developing Resources to Help You on the Beat</a>
<ul>
<li><a href="develop-a-calendar-of-events.html">Develop a Calendar of Events</a></li>
<li><a href="build-your-library.html">Build Your Library</a></li>
<li><a href="learn-the-open-record-laws.html">Learn the Open Record Laws</a></li>
</ul>
</li>
<li><a href="extra-resources.html">Extra Resources</a>
<ul>
<li><a href="beat-breakdown-tool.html">Beat Breakdown Tool</a></li>
<li><a href="links-library.html">Links Library</a>
<ul>
<li><a href="general-resources-for-any-beat.html">General Resources for Any Beat</a></li>
<li><a href="courts-and-criminal-justice-links.html">Courts and Criminal Justice Links</a></li>
<li><a href="education-resources.html">Education Resources</a></li>
<li><a href="local-government-links.html">Local Government Links</a></li>
<li><a href="neighborhood-or-suburban-links.html">Neighborhood or Suburban Links</a></li>
<li><a href="police-and-public-safety-links.html">Police and Public Safety Links</a></li>
<li><a href="reporter-organizations.html">Reporter Organizations</a></li>
</ul>
</li>
<li><a href="additional-reading.html">Additional Reading</a></li>
</ul>
</li>
<li><a href="final-thoughts.html">Final Thoughts</a></li>
</ul>
The jQuery:
function toggleSubmenu() {
if ($(this).hasClass('submenu-hidden')) {
$(this).parent().children('ul').slideToggle();
$(this).removeClass().addClass('submenu-visible');
} else if ($(this).hasClass('submenu-visible')) {
$(this).parent().children('ul').slideToggle();
$(this).removeClass().addClass('submenu-hidden');
}
}
$('#lesson-sidebar ul ul').hide();
$('#lesson-sidebar ul ul ul').hide();
$('#lesson-sidebar ul:first-child').attr('id', 'rootlist');
$('#lesson-sidebar ul li:has("ul")').prepend('<span class="submenu-hidden"></span>').css('list-style','none');
$('#lesson-sidebar ul li a').each(
function() {
if ($(this).hasClass('active')) {
// if it is a UL
var length = $(this).parent().find("ul").length;
alert(length);
if (length == 0) {
if ($(this).parent().parent().parent().children('span').hasClass('submenu-hidden')) {
$(this).parent().parent().parent().children('ul').show();
$(this).parent().parent().parent().children('span').removeClass('submenu-hidden').addClass('submenu-visible');
}
if ($(this).parent().parent().parent().parent().parent().children('span').hasClass('submenu-hidden')) {
$(this).parent().parent().parent().parent().parent().children('ul').show();
$(this).parent().parent().parent().parent().parent().children('span').removeClass('submenu-hidden').addClass('submenu-visible');
}
}
if (length == 1) {
$(this).parent().find('ul').slideToggle();
$(this).parent().children('span').removeClass('submenu-hidden').addClass('submenu-visible');
}
}
}
);
$('ul#rootlist > li span, ul#rootlist li ul li > span').bind('click', toggleSubmenu);
Any and all help is majorly appreciated.
If I understand what you're trying to do... you can do something like this:
// For my benefit, hide all lists except the root items
$('ul, li', $('#lesson-sidebar ul li')).hide();
// Show active parents and their siblings
$('li a.active').parents('ul, li').each(function() {
$(this).siblings().andSelf().show();
});
// Show the active item and its siblings
$('li a.active').siblings().andSelf().show();
The parents() and siblings() methods are both great for this kind of thing.
Edit: There was a bug before where it wasn't showing parent siblings. Try this new version.
Edit 2: Now it works with class="active" on the anchor instead of the list item.
$(this).closest("ul") will traverse the parents until it finds a ul
http://docs.jquery.com/Traversing/closest#expr
...get the first element that matches the selector by testing the element itself and traversing up through its ancestors in the DOM tree...
To simplify Lance McNeary's very helpful answer, the trick is to use:
.parents([selector])
Given a jQuery object that represents a set of DOM elements, the .parents() method allows us to search through the ancestors of these elements in the DOM tree and construct a new jQuery object from the matching elements ordered from immediate parent on up; the elements are returned in order from the closest parent to the outer ones.
Another user suggested:
.closest([selector])
Similar to .parents(), this may be a better choice as it stops once it finds the element it is looking for. Seems like it would be more efficient in this case. See http://api.jquery.com/closest/ for more details. Hope this helps people understand the differences between .closest() and .parents() and how powerful and flexible jQuery can be.
$(this).parents().get()[4] will give you the fifth
Try with this code line:
$(this).parent().parent().fadeOut();
来源：https://stackoverflow.com/questions/2053190/moving-up-multiple-parents-in-jquery-more-efficient-way