Bootstrap dropdown sub menu missing

Bootstrap 3 is still at RC, but I was just trying to implement it. I couldn't figure out how to put a sub menu class. Even there is no class in css and even the new docs don't say anything about it

It was there in 2.x with class name as dropdown-submenu

Bootstrap 5 (update 2021)

Add some JavaScript to prevent the submenu from closing when the parent dropdown is open. This can be done be toggle display:block...

let dropdowns = document.querySelectorAll('.dropdown-toggle')
dropdowns.forEach((dd)=>{
    dd.addEventListener('click', function (e) {
        var el = this.nextElementSibling
        el.style.display = el.style.display==='block'?'none':'block'
    })
})

Bootstrap 5 Multi-level Dropdown - click
Bootstrap 5 Multi-level Dropdown - hover

Or, you can use this CSS only method for Navbar dropdowns...

.dropdown-submenu {
  position: relative;
}

.dropdown-submenu .dropdown-menu {
  top: 0;
  left: 100%;
  margin-top: -1px;
}

.navbar-nav li:hover > ul.dropdown-menu {
    display: block;
}

Bootstrap 5 Navbar Dropdown Hover Submenus (CSS only)

Bootstrap 4 (update 2018)

The dropdown-submenu has been removed in Bootstrap 3 RC. In the words of Bootstrap author Mark Otto..

> "Submenus just don't have much of a place on the web right now, especially the mobile web. They will be removed with 3.0" - https://github.com/twbs/bootstrap/pull/6342

But, with a little extra CSS you can get the same functionality.

navbar submenu on hover:

.navbar-nav li:hover > ul.dropdown-menu {
    display: block;
}
.dropdown-submenu {
    position:relative;
}
.dropdown-submenu>.dropdown-menu {
    top:0;
    left:100%;
    margin-top:-6px;
}

Navbar submenu dropdown hover
Navbar submenu dropdown hover (right aligned)
Navbar submenu dropdown click (right aligned)
Navbar dropdown hover (no submenu)

Bootstrap 3

Here is an example that uses 3.0 RC 1: http://bootply.com/71520</strike>

.dropdown-submenu {
    position:relative;
}
.dropdown-submenu>.dropdown-menu {
    top:0;
    left:100%;
    margin-top:-6px;
    margin-left:-1px;
    -webkit-border-radius:0 6px 6px 6px;
    -moz-border-radius:0 6px 6px 6px;
    border-radius:0 6px 6px 6px;
}
.dropdown-submenu:hover>.dropdown-menu {
    display:block;
}
.dropdown-submenu>a:after {
    display:block;
    content:" ";
    float:right;
    width:0;
    height:0;
    border-color:transparent;
    border-style:solid;
    border-width:5px 0 5px 5px;
    border-left-color:#cccccc;
    margin-top:5px;
    margin-right:-10px;
}
.dropdown-submenu:hover>a:after {
    border-left-color:#ffffff;
}
.dropdown-submenu.pull-left {
    float:none;
}
.dropdown-submenu.pull-left>.dropdown-menu {
    left:-100%;
    margin-left:10px;
    -webkit-border-radius:6px 0 6px 6px;
    -moz-border-radius:6px 0 6px 6px;
    border-radius:6px 0 6px 6px;
}

<div class="navbar navbar-default navbar-fixed-top" role="navigation">
    <div class="container">
        <div class="navbar-header">
            <button type="button" class="navbar-toggle" data-toggle="collapse" data-target=".navbar-ex1-collapse">	
                <span class="sr-only">Toggle navigation</span>
	            <span class="icon-bar"></span>
	            <span class="icon-bar"></span>
	            <span class="icon-bar"></span>
            </button>
        </div>
        <div class="collapse navbar-collapse navbar-ex1-collapse">
            <ul class="nav navbar-nav">
                <li class="menu-item dropdown">
                    <a href="#" class="dropdown-toggle" data-toggle="dropdown">Drop Down<b class="caret"></b></a>
                    <ul class="dropdown-menu">
                        <li class="menu-item dropdown dropdown-submenu">
                            <a href="#" class="dropdown-toggle" data-toggle="dropdown">Level 1</a>
                            <ul class="dropdown-menu">
                                <li class="menu-item ">
                                    <a href="#">Link 1</a>
                                </li>
                                <li class="menu-item dropdown dropdown-submenu">
                                    <a href="#" class="dropdown-toggle" data-toggle="dropdown">Level 2</a>
                                    <ul class="dropdown-menu">
                                        <li>
                                            <a href="#">Link 3</a>
                                        </li>
                                    </ul>
                                </li>
                            </ul>
                        </li>
                    </ul>
                </li>
            </ul>
        </div>
    </div>
</div>

@skelly solution is good but will not work on mobile devices as the hover state won't work.

I have added a little bit of JS to get the BS 2.3.2 behavior back.

PS: it will work with the CSS you get there: http://bootply.com/71520 though you can comment the following part:

CSS:

/*.dropdown-submenu:hover>.dropdown-menu{display:block;}*/

JS:

$('ul.dropdown-menu [data-toggle=dropdown]').on('click', function(event) {
  // Avoid following the href location when clicking
  event.preventDefault();
  // Avoid having the menu to close when clicking
  event.stopPropagation();
  // If a menu is already open we close it
  $('ul.dropdown-menu [data-toggle=dropdown]').parent().removeClass('open');
  // opening the one you clicked on
  $(this).parent().addClass('open');
});

The result can be found on my WordPress theme (Top of the page): http://shprinkone.julienrenaux.fr/

Until today (9 jan 2014) the Bootstrap 3 still not support sub menu dropdown.

I searched Google about responsive navigation menu and found this is the best i though.

It is Smart menus http://www.smartmenus.org/

I hope this is the way out for anyone who want navigation menu with multilevel sub menu.

update 2015-02-17 Smart menus are now fully support Bootstrap element style for submenu. For more information please look at Smart menus website.

Shprink's code helped me the most, but to avoid the dropdown to go off-screen i updated it to:

JS:

$('ul.dropdown-menu [data-toggle=dropdown]').on('click', function(event) {
    // Avoid following the href location when clicking
    event.preventDefault(); 
    // Avoid having the menu to close when clicking
    event.stopPropagation(); 
    // If a menu is already open we close it
    $('ul.dropdown-menu [data-toggle=dropdown]').parent().removeClass('open');
    // opening the one you clicked on
    $(this).parent().addClass('open');
	
	var menu = $(this).parent().find("ul");
	var menupos = $(menu).offset();

	if (menupos.left + menu.width() > $(window).width()) {
		var newpos = -$(menu).width();
		menu.css({ left: newpos });    
	} else {
		var newpos = $(this).parent().width();
		menu.css({ left: newpos });
	}
	
});

CSS: FROM background-color: #eeeeee TO background-color: #c5c5c5 - white font & light background wasn't looking good.

.nav .open > a,
.nav .open > a:hover,
.nav .open > a:focus {
  background-color: #c5c5c5;
  border-color: #428bca;
}

I hope this helps people as much as it did for me!

But i hope Bootstrap add the subs feature back ASAP.

Comment to Skelly's really helpful workaround: in Bootstrap-sass 3.3.6, utilities.scss, line 19: .pull-left has float:left !important. Since that, I recommend to use !important in his CSS as well:

.dropdown-submenu.pull-left {
    float:none !important;
}

With Bootstrap 5, it's now very easy to implement dropdown submenu without using any javascript code thanks to the new autoClose option and dropend class.

Live demo: https://jsfiddle.net/b038kc2y/

.dropdown-menu .dropdown-menu {
  top: -.5rem !important;
}

<div class="dropdown m-5">
  <a class="btn btn-secondary dropdown-toggle" href="#" role="button" id="dropdownMenuLink" data-bs-toggle="dropdown" data-bs-auto-close="outside" aria-expanded="false">
    Dropdown link
  </a>
  <ul class="dropdown-menu" aria-labelledby="dropdownMenuLink">
    <li class="dropend">
      <a class="dropdown-item" href="#" id="dropdownSubMenuLink" data-bs-toggle="dropdown" aria-expanded="false">Submenu Action</a>
      <ul class="dropdown-menu" aria-labelledby="dropdownSubMenuLink">
        <li><a class="dropdown-item" href="#">Another action</a></li>
        <li><a class="dropdown-item" href="#">Something else here</a></li>
      </ul>
    </li>
  </ul>
</div>

I bumped with this issue a few days ago. I tried many solutions and none really worked for me on the end i ended up creating an extenion/override of the dropdown code of bootstrap. It is a copy of the original code with changes to the closeMenus function.

I think it is a good solution since it doesn't affects the core classes of bootstrap js.

You can check it out on gihub: https://github.com/djokodonev/bootstrap-multilevel-dropdown

HTML

<!DOCTYPE html>
<html>
<head>
	<title>Dropdown Navbar</title>
	<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.1/css/bootstrap.min.css">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.5.1/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.1/js/bootstrap.min.js"></script>
<link rel="stylesheet" type="text/css" href="style.css">
</head>

<body>
<nav class="navbar navbar-inverse">
  <div class="container-fluid">
    <div class="navbar-header">
      <button type="button" class="navbar-toggle" data-toggle="collapse" data-target="#myNavbar">
        <span class="icon-bar"></span>
        <span class="icon-bar"></span>
        <span class="icon-bar"></span>
      </button>
      <a class="navbar-brand" href="#">The Providers</a>
    </div>
    <div class="collapse navbar-collapse" id="myNavbar">
      <ul class="nav navbar-nav">
        <li ><a href="#">Home</a></li>
        <li  id="course" class="dropdown" ><a  href="#">Courses<span class="caret"></span></a>
        <ul class="dropdown-menu">
          <li><a href="#">SEO</a></li>
          <li><a href="#">A.I</a></li>
          <li><a href="#">M.L</a></li>
          <li><a href="#">Graphics</a></li>
          <li id="sub-dropdown" class="dropdown"><a href="#">web Design<span style="margin-left: 43px;" class="glyphicon glyphicon-chevron-right"></span> </a>
        <ul id="sub-dropdown-menu" class="dropdown-menu">
          <li><a href="#">HTML</a></li>
          <li><a href="#">CSS</a></li>
          <li><a href="#">Bootstrap 3</a></li>
          <li><a href="#">JavaScript</a></li>
          <li><a href="#">Angular</a></li>
        </ul>
      </li>
          </li>
        </ul>
      </li>
        <li><a href="#">Gallery</a></li>
        <li><a href="#">Contact us</a></li>
        <li><a href="#">Policy</a></li>
      </ul>
    </div>
  </div>
</nav>
</body>
</html>

CSS

body{
    font-family: monospace;
    outline: none;
    background-image: url(image.jpg);
    background-size: cover;
    background-repeat: no-repeat;
    height: 100vh;
}
.navbar-inverse{
	background-color: #2a84eb ;
	border-color: transparent;
}

.navbar-inverse .navbar-brand{
	color: #fff;
	font-size: 30px;
	margin-right: 40px;
}

#myNavbar .navbar-nav li a{
	color: #fff;
	font-size: 19px;
}
#myNavbar #course{
	transition: all 0.3s ease-in-out;
}
#myNavbar #course:hover{
	background-color:#0751a6; 
}	
.dropdown-menu{
  display: none;
  position: absolute;
  background-color: #f0f0f0;
  box-shadow: 2px 8px 16px 0px rgba(0,0,0,0.2);
  z-index: 1;
}

#sub-dropdown-menu{
display: none;
  position: absolute;
  background-color: #f0f0f0;
  margin-left: 186px;
  margin-top: -26px;
}

#sub-dropdown-menu a , .dropdown-menu a {
	color: #000 !important;
    font-size: 16px !important;
}

.dropdown:hover .dropdown-menu {display: block;transition: all 0.5s ease-in-out;}

.dropdown .dropdown-menu a:hover{background-color: #c9c7c7;}

#sub-dropdown:hover #sub-dropdown-menu {display: block;}

Source: https://www.youtube.com/watch?v=6CgnWhJ-amE

I make another solution for dropdown. Hope this is helpfull Just add this js script

<script type="text/javascript"> jQuery("document").ready(function() {
  jQuery("ul.dropdown-menu > .dropdown.parent").click(function(e) {
    e.preventDefault();
    e.stopPropagation();
    if (jQuery(this).hasClass('open2'))
      jQuery(this).removeClass('open2');
    else {
      jQuery(this).addClass('open2');
    }

  });
}); < /script>

<style type="text/css">.open2{display:block; position:relative;}</style>