如何为ul列表添加/删除活动课程？

Question

When clicked the active class is left with the original "li" where it should have changed. I tried messing with the code but was unable to find a solution. can someone please check what I missed. I think I am mssing something specific to my code. I tried "add/remove active class for ul list with jquery?" but that did not help. If you can find the fault in my code it would be great.

Html:

<div class="collapse navbar-collapse navbar-ex1-collapse">
    <ul class="nav navbar-nav navbar-right">
        <li class="active"><a href="#juk">About</a></li>
        <li><a onclick="myFunction1()">Development</a></li>
        <li><a href="http://docs.kde.org/stable/en/kdemultimedia/juk/index.html">Wiki/Documentation</a></li>
        <li><a onclick="myFunction()">Screenshots</a></li>
        <li class="dropdown">
        <a data-toggle="dropdown" class="dropdown-toggle" href="#">Releases </a>
        <ul class="dropdown-menu">
            <li><a href="ftp://ftp.kde.org/pub/kde/stable/latest">JuK Latest</a></li>
            <li><a href="http://developer.kde.org/~wheeler/files/src/juk-1.95a.tar.gz">JuK 1.95</a></li>
            <li><a href="http://developer.kde.org/~wheeler/files/src/juk-1.1.tar.gz">JuK 1.1</a></li>
            <li><a href="http://developer.kde.org/~wheeler/files/src/juk-1.0-1.tar.gz">JuK 1.0</a></li>
        </ul>
        </li>
        <li><a href="#contactus">Contact Us</a></li>
    </ul>
</div>

JS:

$(function() {
    ( 'ul.nav.navbar-nav.navbar-right li' ).on( 'click', function() {
        $( this ).parent().find( 'li.active' ).removeClass( 'active' );
        $( this ).addClass( 'active' );
    });
});

Answer 1

You are targeting the wrong <li> element in the .on('click') event

You said

$( 'ul.nav navbar-nav navbar-right li' )

Which will look for li that is a child of navbar-right that is also a child of navbar-nav that is also a child of ul.nva .

What you should have targeted is:

$( 'ul.nav.navbar-nav.navbar-right li' )

Notice the space before the li ? that is because it is a descendant of the ul element that has multiple classes.

I know you copied the class list from the HTML DOM element, but you have to avoid spaces in jQuery selector if you are talking about a single element that has multiple classes.

 $(function() { $('ul.nav.navbar-nav.navbar-right li').on('click', function() { $(this).parent().find('li.active').removeClass('active'); $(this).addClass('active'); }); }); 

 .active { background-color: gold; } 

 <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/1.10.1/jquery.min.js"></script> <div class="collapse navbar-collapse navbar-ex1-collapse"> <ul class="nav navbar-nav navbar-right"> <li class="active"><a href="#juk">About</a></li> <li><a>Development</a></li> <li><a href="#">Wiki/Documentation</a></li> <li><a >Screenshots</a></li> <li class="dropdown"> <a data-toggle="dropdown" class="dropdown-toggle" href="#">Releases </a> <ul class="dropdown-menu"> <li><a href="#">JuK Latest</a></li> <li><a href="#">JuK 1.95</a></li> <li><a href="#">JuK 1.1</a></li> <li><a href="#">JuK 1.0</a></li> </ul> </li> <li><a href="#contactus">Contact Us</a></li> </ul> </div>