<link href="//maxcdn.bootstrapcdn.com/bootstrap/3.3.0/css/bootstrap.min.css" rel="stylesheet" id="bootstrap-css"> <script src="//maxcdn.bootstrapcdn.com/bootstrap/3.3.0/js/bootstrap.min.js"></script> <script src="//code.jquery.com/jquery-1.11.1.min.js"></script> <!------ Include the above in your HEAD tag ----------> <div class="btn-group" id="myDropdown"> <a class="btn dropdown-toggle" data-toggle="dropdown" href="#"> Menu <span class="caret"></span> </a> <ul class="dropdown-menu"> <li><a href="#">Choice1</a></li> <li><a href="#">Choice2</a></li> <li><a href="#">Choice3</a></li> <li class="divider"></li> <li><a href="#">Choice..</a></li> </ul> </div>

alert("working"); $('#myDropdown').on('show.bs.dropdown', function () { alert('hello'); })