Bootstrap multilevel dropdown

by Petr Haluza

HTML

<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/twitter-bootstrap/4.3.1/css/bootstrap.min.css">
<script src="//code.jquery.com/jquery-3.3.1.slim.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/twitter-bootstrap/4.3.1/js/bootstrap.bundle.min.js"></script>
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/font-awesome/4.7.0/css/font-awesome.min.css">
<nav class="navbar navbar-expand-lg navbar-light bg-white py-3 shadow-sm">
  <div class="container">
    <a href="#" class="navbar-brand font-weight-bold">Multilevel Dropdown</a>
    <button type="button" data-toggle="collapse" data-target="#navbarContent" aria-controls="navbars" aria-expanded="false" aria-label="Toggle navigation" class="navbar-toggler">
              <span class="navbar-toggler-icon"></span>
          </button>


    <div id="navbarContent" class="collapse navbar-collapse">
      <ul class="navbar-nav mr-auto">
        <!-- Level one dropdown -->
        <li class="nav-item dropdown">
          <a id="dropdownMenu1" href="#" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false" class="nav-link dropdown-toggle">Dropdown</a>
          <ul aria-labelledby="dropdownMenu1" class="dropdown-menu border-0 shadow">

            <li class="dropdown-submenu">
              <a id="dropdownMenu2" href="#" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false" class="dropdown-item dropdown-toggle">Marketing</a>
              <ul aria-labelledby="dropdownMenu2" class="dropdown-menu border-0 shadow">
                <li>
                  <a tabindex="-1" href="#" class="dropdown-item">level 2</a>
                </li>

                <!-- Level three dropdown-->
                <li class="dropdown-submenu">
                  <a id="dropdownMenu3" href="#" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false" class="dropdown-item dropdown-toggle">level 2</a>
                  <ul...

CSS

/*
*
* ==========================================
* CUSTOM UTIL CLASSES
* ==========================================
*
*/

.dropdown-submenu {
  position: relative;
}

.dropdown-submenu>a:after {
  content: "\f0da";
  float: right;
  border: none;
  font-family: 'FontAwesome';
}

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

/*
*
* ==========================================
* FOR DEMO PURPOSES
* ==========================================
*
*/

body {
  background: #4568DC;
  background: -webkit-linear-gradient(to right, #4568DC, #B06AB3);
  background: linear-gradient(to right, #4568DC, #B06AB3);
  min-height: 100vh;
}

code {
  color: #B06AB3;
  background: #fff;
  padding: 0.1rem 0.2rem;
  border-radius: 0.2rem;
}

@media (min-width: 991px) {
  .dropdown-menu {
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
  }
}

JavaScript

$(function() {
  // ------------------------------------------------------- //
  // Multi Level dropdowns
  // ------------------------------------------------------ //
  $("ul.dropdown-menu [data-toggle='dropdown']").on("click", function(event) {
    event.preventDefault();
    event.stopPropagation();

    $(this).siblings().toggleClass("show");


    if (!$(this).next().hasClass('show')) {
      $(this).parents('.dropdown-menu').first().find('.show').removeClass("show");
    }
    $(this).parents('li.nav-item.dropdown.show').on('hidden.bs.dropdown', function(e) {
      $('.dropdown-submenu .show').removeClass("show");
    });

  });
});