A dropdown menu is a toggleable menu that allows the user to choose one value from a predefined list:
<div class="dropdown">
<button class="btn btn-primary dropdown-toggle" type="button" data-toggle="dropdown">Dropdown Example
<span class="caret"></span></button>
<ul class="dropdown-menu">
<li><a href="#">HTML</a></li>
<li><a href="#">CSS</a></li>
<li><a href="#">JavaScript</a></li>
</ul>
</div>
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The .dropdown
class indicates a dropdown menu.
To open the dropdown menu, use a button or a link with a class of .dropdown-toggle
and the data-toggle="dropdown"
attribute.
The .caret
class creates a caret arrow icon (), which indicates that the button is a dropdown.
Add the .dropdown-menu
class to a <ul>
element to actually build the dropdown menu.
The .divider
class is used to separate links inside the dropdown menu with a thin horizontal border:
The .dropdown-header
class is used to add headers inside the dropdown menu:
Highlight a specific dropdown item with the .active class (adds a blue background color).
To disable an item in the dropdown menu, use the .disabled
class (gets a light-grey text color and a "no-parking-sign" icon on hover):
<li class="disabled"><a href="#">CSS</a></li>
<li class="active"><a href="#">HTML</a></li>
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To right-align the dropdown, add the .dropdown-menu-right
class to the element with .dropdown-menu:
If you want the dropdown menu to expand upwards instead of downwards, change the <div> element with class="dropdown" to "dropup"
:
To help improve accessibility for people using screen readers, you should include the following role
and aria-*
attributes, when creating a dropdown menu:
<div class="dropdown">
<button class="btn btn-default dropdown-toggle" type="button" id="menu1" data-toggle="dropdown">Tutorials
<span class="caret"></span></button>
<ul class="dropdown-menu" role="menu" aria-labelledby="menu1">
<li role="presentation"><a role="menuitem" href="#">HTML</a></li>
<li role="presentation"><a role="menuitem" href="#">CSS</a></li>
<li role="presentation"><a role="menuitem" href="#">JavaScript</a></li>
<li role="presentation" class="divider"></li>
<li role="presentation"><a role="menuitem" href="#">About Us</a></li>
</ul>
</div>
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For a complete reference of all dropdown options, methods and events, go to our Bootstrap JS Dropdown Reference.
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