--- layout: page title: Dropdowns --- Toggleable, contextual menu for displaying lists of links. Made interactive with the [dropdown JavaScript plugin]({{ site.bsaeurl }}javascript/#dropdowns). ### Example Wrap the dropdown's trigger and the dropdown menu within `.dropdown`, or another element that declares `position: relative;`. Then add the menu's HTML. {% example html %} <div class="dropdown"> <button class="btn btn-secondary dropdown-toggle" type="button" id="dropdownMenu1" data-toggle="dropdown"> Dropdown </button> <ul class="dropdown-menu" role="menu" aria-labelledby="dropdownMenu1"> <li role="presentation"> <a role="menuitem" tabindex="-1" href="#">Action</a> </li> <li role="presentation"> <a role="menuitem" tabindex="-1" href="#">Another action</a> </li> <li role="presentation"> <a role="menuitem" tabindex="-1" href="#">Something else here</a> </li> </ul> </div> {% endexample %} ### Alignment By default, a dropdown menu is automatically positioned 100% from the top and along the left side of its parent. Add `.dropdown-menu-right` to a `.dropdown-menu` to right align the dropdown menu. <div class="bs-callout bs-callout-warning"> <h4>May require additional positioning</h4> <p>Dropdowns are automatically positioned via CSS within the normal flow of the document. This means dropdowns may be cropped by parents with certain <code>overflow</code> properties or appear out of bounds of the viewport. Address these issues on your own as they arise.</p> </div> {% highlight html %} <ul class="dropdown-menu dropdown-menu-right" role="menu" aria-labelledby="dLabel"> ... </ul> {% endhighlight %} ### Menu headers Add a header to label sections of actions in any dropdown menu. {% example html %} <ul class="dropdown-menu" role="menu"> <li role="presentation" class="dropdown-header">Dropdown header</li> <li role="presentation"> <a role="menuitem" tabindex="-1" href="#">Action</a> </li> <li role="presentation"> <a role="menuitem" tabindex="-1" href="#">Another action</a> </li> </ul> {% endexample %} ### Menu dividers Separate groups of related menu items with a divider. {% example html %} <ul class="dropdown-menu" role="menu"> <li role="presentation"> <a role="menuitem" tabindex="-1" href="#">Action</a> </li> <li role="presentation"> <a role="menuitem" tabindex="-1" href="#">Another action</a> </li> <li role="presentation"> <a role="menuitem" tabindex="-1" href="#">Something else here</a> </li> <li role="presentation" class="dropdown-divider"></li> <li role="presentation"> <a role="menuitem" tabindex="-1" href="#">Separated link</a> </li> </ul> {% endexample %} ### Disabled menu items Add `.disabled` to a `<li>` in the dropdown to disable the link. {% example html %} <ul class="dropdown-menu" role="menu" aria-labelledby="dropdownMenu3"> <li role="presentation"> <a role="menuitem" tabindex="-1" href="#">Regular link</a> </li> <li role="presentation" class="disabled"> <a role="menuitem" tabindex="-1" href="#">Disabled link</a> </li> <li role="presentation"> <a role="menuitem" tabindex="-1" href="#">Another link</a> </li> </ul> {% endexample %}