Horizontal submenu for a vertical main menu using

Question

Is there any way to create a horizontal submenu for a vertical menu structure using bootstrap I haven't seen any submenus with vertical main menu orientation. A sample structure of the menu structure is similar to this

Answer 1

This could be helpful for you. can be found here

HTML:

<div class="container-fluid">
    <ul class="nav nav-justified navbar-default">
      <li class="dropdown">
        <a href="#" data-toggle="collapse" data-target="#one">One</a>
      </li>
      <li class="dropdown">
        <a href="#" data-toggle="collapse" data-target="#two">Two</a>
      </li>
      <li class="dropdown">
        <a href="#" data-toggle="collapse" data-target="#three">Three</a>
      </li>
      <li class="dropdown">
        <a href="#" data-toggle="collapse" data-target="#four">Four</a>
      </li>
      <li class="dropdown">
        <a href="#" data-toggle="collapse" data-target="#five">Five</a>
      </li>
    </ul>
</div>
<div class="container-fluid">
  <nav id="submenu">
    <ul class="nav nav-justified">
      <li>
        <ul class="nav nav-justified collapse" id="one">
          <li><a href="#" id="">One sub 1</a></li>
          <li><a href="#" id="">One sub 2</a></li>
          <li><a href="#" id="">One sub 3</a></li>
          <li><a href="#" id="">One sub 4</a></li>
        </ul>
       </li>
       <li>
         <ul class="nav nav-justified collapse" id="two">
            <li><a href="#" id="">Two sub 1</a></li>
            <li><a href="#" id="">Two sub 2</a></li>
            <li><a href="#" id="">Two sub 3</a></li>
          </ul>
       </li>
       <li>
          <ul class="nav nav-justified collapse" id="three">
            <li><a href="#" id="">Three sub 1</a></li>
            <li><a href="#" id="">Three sub 2</a></li>
          </ul>
       </li>
       <li>
          <ul class="nav nav-justified collapse" id="four">
            <li><a href="#" id="">Four sub 1</a></li>
            <li><a href="#" id="">Four sub 2</a></li>
          </ul>
       </li>
       <li>
          <ul class="nav nav-justified collapse" id="five">
            <li><a href="#" id="">Link</a></li>
            <li><a href="#" id="">Link</a></li>
          </ul>
       </li>
    </ul>
  </nav>
</div>

CSS:

.navbar {
    margin-bottom:-1px;
    border-radius:0;
}

    #submenu {

      background-color: none;
      margin-bottom:10px;
      padding-bottom:15px;
      margin-top:-20px
      margin-left:10px;
      margin-right:10px;
      display:none;
    }

    .collapsing {
      display:none;
    }
    #submenu.navbar {
      background-color:transparent;
      border:0;
    }

JS:

$('.collapse').on('shown.bs.collapse', function (e) {
  $('.collapse').not(this).removeClass('in');
});

$('[data-toggle=collapse]').click(function (e) {
  $('[data-toggle=collapse]').parent('li').removeClass('active');
  $(this).parent('li').toggleClass('active');
  $("#submenu").show();
});

Answer 2

Here we go!

Dropdown menus work with nested "ul", absolute positions and we will change from display: none; to display:block; when needed with hovers.

Something like this:

<ul>
  <li><a href="#">…</a>
    <ul>
      <li><a href="#">…</a>
        <ul> … <!-- And so on. -->
        </ul>
      </li>
  <li>
</ul>

Your example's html

<nav id="main-nav">
  <ul>
    <li><a href="#">Home</a></li>
    <li><a href="#">About</a></li>
    <li><a href="#">Projects</a>
      <ul>
        <li><a href="#">Project 1</a>
          <ul>
            <li><a href="#">Project 2</a>
              <ul>
                <li><a href="#">Project 3</a>
                  <ul>
                    <li><a href="#">Project 4</a>
                      <ul>
                        <li><a href="#">Project 5</a></li>
                      </ul>
                    </li>
                  </ul>
                </li>
              </ul>
            </li>
          </ul>
        </li>
      </ul>
    </li>
    <li><a href="#">Contact</a></li>
  </ul>
</nav>

Your explame's SCSS: (I used sass because it's easier to read and write but i will also paste CSS below)

#main-nav{
  ul{ /* Those lines are used only for styling */
    margin: 0;
    padding: 0;
    border-right: 1px solid black;
    width: 150px;
    list-style-type: none;
    li{
      position: relative; /* This is important when using absolute positions. */
      &:hover{
        &:before{ /* arrow styles */
              content: "";
              top: 0;
              bottom: 0;
              right: 0;
              border-top: 5px solid transparent;
              border-right: 5px solid #999;
              border-bottom: 5px solid transparent;
              border-left: 5px solid transparent;
              position: absolute;
              height: 0px;
              width: 0px;
              margin: auto;
        }
        > ul{
          display: block; /* IMPORTANT: This will show your dropdown menus when hover in the parent li. */

          /*&:before { // I don't like this part but if you enable it, it will make child ul's look closer to your design.
              content: "";
              position: absolute;
              right: 0;
              top: -65px;
              bottom: -35px;
              width: 1px;
              background-color: #ccc;
          }*/
        }
      }//:hover

      a{ /* Those lines are used only for styling */
        padding: 7px 10px;
        display: block;
        &:hover{
          color: red;
        }
      }// a

      > ul{ /* This is what makes the magic happen. */
        display: none; /* Dropdown menus are always hidden, except when you hover it's li parent */
        position: absolute; /* This will position the ul */
        top: 0;
        left: 100%; /* This will push the ul where it is needed. */
        border-right: 1px solid #ccc;
      }
    }// li
  }// ul
}

A live example: https://jsfiddle.net/xwazzo/3spxxk1z/

And the promised CSS version:

#main-nav ul {
  margin: 0;
  padding: 0;
  border-right: 1px solid black;
  width: 150px;
  list-style-type: none; 
}

#main-nav ul li { position: relative; }
#main-nav ul li:hover:before {
  content: "";
  top: 0;
  bottom: 0;
  right: 0;
  border-top: 5px solid transparent;
  border-right: 5px solid #999;
  border-bottom: 5px solid transparent;
  border-left: 5px solid transparent;
  position: absolute;
  height: 0px;
  width: 0px;
  margin: auto; 
}

#main-nav ul li:hover > ul { display: block; }
#main-nav ul li a {
  padding: 7px 10px;
  display: block; 
}

#main-nav ul li a:hover { color: red; }
#main-nav ul li > ul {
  display: none;
  position: absolute;
  top: 0;
  left: 100%;
  border-right: 1px solid #ccc; 
}