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Bootstrap/docs/4.0/components/dropdowns.md

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---
layout: docs
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title: Dropdowns
description: Toggle contextual overlays for displaying lists of links and more with the Bootstrap dropdown plugin.
group: components
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toc: true
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---
## Overview
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Dropdowns are toggleable, contextual overlays for displaying lists of links and more. They're made interactive with the included Bootstrap dropdown JavaScript plugin. They're toggled by clicking, not by hovering; this is [an intentional design decision.](http://markdotto.com/2012/02/27/bootstrap-explained-dropdowns/)
Dropdowns are built on a third party library, [Popper.js](https://popper.js.org/), which provides dynamic positioning and viewport detection. Be sure to include [popper.min.js]({{ site.cdn.popper }}) before Bootstrap's JavaScript or use `bootstrap.bundle.min.js` / `bootstrap.bundle.js` which contains Popper.js. Popper.js isn't used to position dropdowns in navbars though as dynamic positioning isn't required.
If you're building our JavaScript from source, it [requires `util.js`]({{ site.baseurl }}/docs/{{ site.docs_version }}/getting-started/javascript/#util).
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## Accessibility
The [<abbr title="Web Accessibility Initiative">WAI</abbr> <abbr title="Accessible Rich Internet Applications">ARIA</abbr>](https://www.w3.org/TR/wai-aria/) standard defines an actual [`role="menu"` widget](https://www.w3.org/TR/wai-aria/roles#menu), but this is specific to application-like menus which trigger actions or functions. <abbr title="Accessible Rich Internet Applications">ARIA</abbr> menus can only contain menu items, checkbox menu items, radio button menu items, radio button groups, and sub-menus.
Bootstrap's dropdowns, on the other hand, are designed to be generic and applicable to a variety of situations and markup structures. For instance, it is possible to create dropdowns that contain additional inputs and form controls, such as search fields or login forms. For this reason, Bootstrap does not expect (nor automatically add) any of the `role` and `aria-` attributes required for true <abbr title="Accessible Rich Internet Applications">ARIA</abbr> menus. Authors will have to include these more specific attributes themselves.
However, Bootstrap does add built-in support for most standard keyboard menu interactions, such as the ability to move through individual `.dropdown-item` elements using the cursor keys and close the menu with the <kbd>ESC</kbd> key.
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## Examples
Wrap the dropdown's toggle (your button or link) and the dropdown menu within `.dropdown`, or another element that declares `position: relative;`. Dropdowns can be triggered from `<a>` or `<button>` elements to better fit your potential needs.
### Single button dropdowns
Any single `.btn` can be turned into a dropdown toggle with some markup changes. Here's how you can put them to work with either `<button>` elements:
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{% example html %}
<div class="dropdown">
<button class="btn btn-secondary dropdown-toggle" type="button" id="dropdownMenuButton" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
Dropdown button
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</button>
<div class="dropdown-menu" aria-labelledby="dropdownMenuButton">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
</div>
</div>
{% endexample %}
And with `<a>` elements:
{% example html %}
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<div class="dropdown show">
<a class="btn btn-secondary dropdown-toggle" href="#" role="button" id="dropdownMenuLink" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
Dropdown link
</a>
<div class="dropdown-menu" aria-labelledby="dropdownMenuLink">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
</div>
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</div>
{% endexample %}
The best part is you can do this with any button variant, too:
<div class="bd-example">
<div class="btn-group">
<button type="button" class="btn btn-primary dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">Primary</button>
<div class="dropdown-menu">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
<div class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Separated link</a>
</div>
</div><!-- /btn-group -->
<div class="btn-group">
<button type="button" class="btn btn-secondary dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">Secondary</button>
<div class="dropdown-menu">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
<div class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Separated link</a>
</div>
</div><!-- /btn-group -->
<div class="btn-group">
<button type="button" class="btn btn-success dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">Success</button>
<div class="dropdown-menu">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
<div class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Separated link</a>
</div>
</div><!-- /btn-group -->
<div class="btn-group">
<button type="button" class="btn btn-info dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">Info</button>
<div class="dropdown-menu">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
<div class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Separated link</a>
</div>
</div><!-- /btn-group -->
<div class="btn-group">
<button type="button" class="btn btn-warning dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">Warning</button>
<div class="dropdown-menu">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
<div class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Separated link</a>
</div>
</div><!-- /btn-group -->
<div class="btn-group">
<button type="button" class="btn btn-danger dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">Danger</button>
<div class="dropdown-menu">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
<div class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Separated link</a>
</div>
</div><!-- /btn-group -->
</div>
{% highlight html %}
<!-- Example single danger button -->
<div class="btn-group">
<button type="button" class="btn btn-danger dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
Action
</button>
<div class="dropdown-menu">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
<div class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Separated link</a>
</div>
</div>
{% endhighlight %}
### Split button dropdowns
Similarly, create split button dropdowns with virtually the same markup as single button dropdowns, but with the addition of `.dropdown-toggle-split` for proper spacing around the dropdown caret.
We use this extra class to reduce the horizontal `padding` on either side of the caret by 25% and remove the `margin-left` that's added for regular button dropdowns. Those extra changes keep the caret centered in the split button and provide a more appropriately sized hit area next to the main button.
<div class="bd-example">
<div class="btn-group">
<button type="button" class="btn btn-primary">Primary</button>
<button type="button" class="btn btn-primary dropdown-toggle dropdown-toggle-split" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
<span class="sr-only">Toggle Dropdown</span>
</button>
<div class="dropdown-menu">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
<div class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Separated link</a>
</div>
</div><!-- /btn-group -->
<div class="btn-group">
<button type="button" class="btn btn-secondary">Secondary</button>
<button type="button" class="btn btn-secondary dropdown-toggle dropdown-toggle-split" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
<span class="sr-only">Toggle Dropdown</span>
</button>
<div class="dropdown-menu">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
<div class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Separated link</a>
</div>
</div><!-- /btn-group -->
<div class="btn-group">
<button type="button" class="btn btn-success">Success</button>
<button type="button" class="btn btn-success dropdown-toggle dropdown-toggle-split" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
<span class="sr-only">Toggle Dropdown</span>
</button>
<div class="dropdown-menu">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
<div class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Separated link</a>
</div>
</div><!-- /btn-group -->
<div class="btn-group">
<button type="button" class="btn btn-info">Info</button>
<button type="button" class="btn btn-info dropdown-toggle dropdown-toggle-split" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
<span class="sr-only">Toggle Dropdown</span>
</button>
<div class="dropdown-menu">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
<div class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Separated link</a>
</div>
</div><!-- /btn-group -->
<div class="btn-group">
<button type="button" class="btn btn-warning">Warning</button>
<button type="button" class="btn btn-warning dropdown-toggle dropdown-toggle-split" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
<span class="sr-only">Toggle Dropdown</span>
</button>
<div class="dropdown-menu">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
<div class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Separated link</a>
</div>
</div><!-- /btn-group -->
<div class="btn-group">
<button type="button" class="btn btn-danger">Danger</button>
<button type="button" class="btn btn-danger dropdown-toggle dropdown-toggle-split" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
<span class="sr-only">Toggle Dropdown</span>
</button>
<div class="dropdown-menu">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
<div class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Separated link</a>
</div>
</div><!-- /btn-group -->
</div>
{% highlight html %}
<!-- Example split danger button -->
<div class="btn-group">
<button type="button" class="btn btn-danger">Action</button>
<button type="button" class="btn btn-danger dropdown-toggle dropdown-toggle-split" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
<span class="sr-only">Toggle Dropdown</span>
</button>
<div class="dropdown-menu">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
<div class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Separated link</a>
</div>
</div>
{% endhighlight %}
## Sizing
Button dropdowns work with buttons of all sizes, including default and split dropdown buttons.
<div class="bd-example">
<div class="btn-toolbar" role="toolbar">
<div class="btn-group">
<button class="btn btn-secondary btn-lg dropdown-toggle" type="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
Large button
</button>
<div class="dropdown-menu">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
<div class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Separated link</a>
</div>
</div><!-- /btn-group -->
<div class="btn-group ml-2">
<button type="button" class="btn btn-lg btn-secondary">Large split button</button>
<button type="button" class="btn btn-lg btn-secondary dropdown-toggle dropdown-toggle-split" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
<span class="sr-only">Toggle Dropdown</span>
</button>
<div class="dropdown-menu">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
<div class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Separated link</a>
</div>
</div><!-- /btn-group -->
</div><!-- /btn-toolbar -->
<div class="btn-toolbar" role="toolbar">
<div class="btn-group">
<button class="btn btn-secondary btn-sm dropdown-toggle" type="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
Small button
</button>
<div class="dropdown-menu">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
<div class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Separated link</a>
</div>
</div><!-- /btn-group -->
<div class="btn-group ml-2">
<button type="button" class="btn btn-sm btn-secondary">Small split button</button>
<button type="button" class="btn btn-sm btn-secondary dropdown-toggle dropdown-toggle-split" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
<span class="sr-only">Toggle Dropdown</span>
</button>
<div class="dropdown-menu">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
<div class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Separated link</a>
</div>
</div><!-- /btn-group -->
</div><!-- /btn-toolbar -->
</div><!-- /example -->
{% highlight html %}
<!-- Large button groups (default and split) -->
<div class="btn-group">
<button class="btn btn-secondary btn-lg dropdown-toggle" type="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
Large button
</button>
<div class="dropdown-menu">
...
</div>
</div>
<div class="btn-group">
<button class="btn btn-secondary btn-lg" type="button">
Large button
</button>
<button type="button" class="btn btn-lg btn-secondary dropdown-toggle dropdown-toggle-split" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
<span class="sr-only">Toggle Dropdown</span>
</button>
<div class="dropdown-menu">
...
</div>
</div>
<!-- Small button groups (default and split) -->
<div class="btn-group">
<button class="btn btn-secondary btn-sm dropdown-toggle" type="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
Small button
</button>
<div class="dropdown-menu">
...
</div>
</div>
<div class="btn-group">
<button class="btn btn-secondary btn-sm" type="button">
Small button
</button>
<button type="button" class="btn btn-sm btn-secondary dropdown-toggle dropdown-toggle-split" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
<span class="sr-only">Toggle Dropdown</span>
</button>
<div class="dropdown-menu">
...
</div>
</div>
{% endhighlight %}
## Dropup variation
Trigger dropdown menus above elements by adding `.dropup` to the parent element.
<div class="bd-example">
<div class="btn-group dropup">
<button type="button" class="btn btn-secondary dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
Dropup
</button>
<div class="dropdown-menu">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
<div class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Separated link</a>
</div>
</div>
<div class="btn-group dropup">
<button type="button" class="btn btn-secondary">
Split dropup
</button>
<button type="button" class="btn btn-secondary dropdown-toggle dropdown-toggle-split" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
<span class="sr-only">Toggle Dropdown</span>
</button>
<div class="dropdown-menu">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
<div class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Separated link</a>
</div>
</div>
</div>
{% highlight html %}
<!-- Default dropup button -->
<div class="btn-group dropup">
<button type="button" class="btn btn-secondary dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
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Dropup
</button>
<div class="dropdown-menu">
<!-- Dropdown menu links -->
</div>
</div>
<!-- Split dropup button -->
<div class="btn-group dropup">
<button type="button" class="btn btn-secondary">
Split dropup
</button>
<button type="button" class="btn btn-secondary dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
<span class="sr-only">Toggle Dropdown</span>
</button>
<div class="dropdown-menu">
<!-- Dropdown menu links -->
</div>
</div>
{% endhighlight %}
## Dropright variation
Trigger dropdown menus at the right of the elements by adding `.dropright` to the parent element.
<div class="bd-example">
<div class="btn-group dropright">
<button type="button" class="btn btn-secondary dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
Dropright
</button>
<div class="dropdown-menu">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
<div class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Separated link</a>
</div>
</div>
<div class="btn-group dropright">
<button type="button" class="btn btn-secondary">
Split dropright
</button>
<button type="button" class="btn btn-secondary dropdown-toggle dropdown-toggle-split" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
<span class="sr-only">Toggle Dropdright</span>
</button>
<div class="dropdown-menu">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
<div class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Separated link</a>
</div>
</div>
</div>
{% highlight html %}
<!-- Default dropright button -->
<div class="btn-group dropright">
<button type="button" class="btn btn-secondary">Dropright</button>
<button type="button" class="btn btn-secondary dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
<span class="sr-only">Toggle Dropright</span>
</button>
<div class="dropdown-menu">
<!-- Dropdown menu links -->
</div>
</div>
<!-- Split dropright button -->
<div class="btn-group dropright">
<button type="button" class="btn btn-secondary">
Split dropright
</button>
<button type="button" class="btn btn-secondary dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
<span class="sr-only">Toggle Dropright</span>
</button>
<div class="dropdown-menu">
<!-- Dropdown menu links -->
</div>
</div>
{% endhighlight %}
## Dropleft variation
Trigger dropdown menus at the left of the elements by adding `.dropleft` to the parent element.
<div class="bd-example">
<div class="btn-group dropleft">
<button type="button" class="btn btn-secondary dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
Dropleft
</button>
<div class="dropdown-menu">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
<div class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Separated link</a>
</div>
</div>
<div class="btn-group">
<div class="btn-group dropleft" role="group">
<button type="button" class="btn btn-secondary dropdown-toggle dropdown-toggle-split" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
<span class="sr-only">Toggle Dropleft</span>
</button>
<div class="dropdown-menu">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
<div class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Separated link</a>
</div>
</div>
<button type="button" class="btn btn-secondary">
Split dropleft
</button>
</div>
</div>
{% highlight html %}
<!-- Default dropleft button -->
<div class="btn-group dropleft">
<button type="button" class="btn btn-secondary dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
Dropleft
</button>
<div class="dropdown-menu">
<!-- Dropdown menu links -->
</div>
</div>
<!-- Split dropleft button -->
<div class="btn-group">
<div class="btn-group dropleft" role="group">
<button type="button" class="btn btn-secondary dropdown-toggle dropdown-toggle-split" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
<span class="sr-only">Toggle Dropleft</span>
</button>
<div class="dropdown-menu">
<!-- Dropdown menu links -->
</div>
</div>
<button type="button" class="btn btn-secondary">
Split dropleft
</button>
</div>
{% endhighlight %}
## Menu items
Historically dropdown menu contents *had* to be links, but that's no longer the case with v4. Now you can optionally use `<button>` elements in your dropdowns instead of just `<a>`s.
{% example html %}
<div class="dropdown">
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<button class="btn btn-secondary dropdown-toggle" type="button" id="dropdownMenu2" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
Dropdown
</button>
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<div class="dropdown-menu" aria-labelledby="dropdownMenu2">
<button class="dropdown-item" type="button">Action</button>
<button class="dropdown-item" type="button">Another action</button>
<button class="dropdown-item" type="button">Something else here</button>
</div>
</div>
{% endexample %}
## Menu alignment
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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.
{% callout info %}
**Heads up!** Dropdowns are positioned thanks to Popper.js (except when they are contained in a navbar).
{% endcallout %}
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{% example html %}
<div class="btn-group">
<button type="button" class="btn btn-secondary dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
This dropdown's menu is right-aligned
</button>
<div class="dropdown-menu dropdown-menu-right">
<button class="dropdown-item" type="button">Action</button>
<button class="dropdown-item" type="button">Another action</button>
<button class="dropdown-item" type="button">Something else here</button>
</div>
</div>
{% endexample %}
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## Menu headers
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Add a header to label sections of actions in any dropdown menu.
{% example html %}
<div class="dropdown-menu">
<h6 class="dropdown-header">Dropdown header</h6>
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
</div>
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{% endexample %}
## Menu dividers
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Separate groups of related menu items with a divider.
{% example html %}
<div class="dropdown-menu">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
<div class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Separated link</a>
</div>
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{% endexample %}
## Menu forms
Put a form within a dropdown menu, or make it into a dropdown menu, and use [margin or padding utilities]({{ site.baseurl }}/docs/{{ site.docs_version }}/utilities/spacing/) to give it the negative space you require.
{% example html %}
<div class="dropdown-menu">
<form class="px-4 py-3">
<div class="form-group">
<label for="exampleDropdownFormEmail1">Email address</label>
<input type="email" class="form-control" id="exampleDropdownFormEmail1" placeholder="email@example.com">
</div>
<div class="form-group">
<label for="exampleDropdownFormPassword1">Password</label>
<input type="password" class="form-control" id="exampleDropdownFormPassword1" placeholder="Password">
</div>
<div class="form-check">
<label class="form-check-label">
<input type="checkbox" class="form-check-input">
Remember me
</label>
</div>
<button type="submit" class="btn btn-primary">Sign in</button>
</form>
<div class="dropdown-divider"></div>
<a class="dropdown-item" href="#">New around here? Sign up</a>
<a class="dropdown-item" href="#">Forgot password?</a>
</div>
{% endexample %}
{% example html %}
<form class="dropdown-menu p-4">
<div class="form-group">
<label for="exampleDropdownFormEmail2">Email address</label>
<input type="email" class="form-control" id="exampleDropdownFormEmail2" placeholder="email@example.com">
</div>
<div class="form-group">
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<label for="exampleDropdownFormPassword2">Password</label>
<input type="password" class="form-control" id="exampleDropdownFormPassword2" placeholder="Password">
</div>
<div class="form-check">
<label class="form-check-label">
<input type="checkbox" class="form-check-input">
Remember me
</label>
</div>
<button type="submit" class="btn btn-primary">Sign in</button>
</form>
{% endexample %}
## Disabled menu items
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Add `.disabled` to items in the dropdown to **style them as disabled**.
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{% example html %}
<div class="dropdown-menu">
<a class="dropdown-item" href="#">Regular link</a>
<a class="dropdown-item disabled" href="#">Disabled link</a>
<a class="dropdown-item" href="#">Another link</a>
</div>
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{% endexample %}
## Usage
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Via data attributes or JavaScript, the dropdown plugin toggles hidden content (dropdown menus) by toggling the `.show` class on the parent list item. The `data-toggle="dropdown"` attribute is relied on for closing dropdown menus at an application level, so it's a good idea to always use it.
Replace dropdown backdrop hack with cleaner JS-only hack * Replace backdrop with simple noop mouse listener As discussed in https://github.com/twbs/bootstrap/pull/22422 the current approach of injecting a backdrop (to work around iOS' broken event delegation for the `click` event) has annoying consequences on touch-enabled laptop/desktop devices. Instead of a backdrop `<div>`, here we simply add extra empty/noop mouse listeners to the immediate children of `<body>` (and remove them when the dropdown is closed) in order to force iOS to properly bubble a `click` resulting from a tap (essentially, method 2 from https://www.quirksmode.org/blog/archives/2014/02/mouse_event_bub.html) This is sufficient (except in rare cases where the user does manage to tap on the body itself, rather than any child elements of body - which is not very likely in an iOS phone/tablet scenario for most layouts) to get iOS to get a grip and do the correct event bubbling/delegation, meaning the regular "click" event will bubble back to the `<body>` when tapping outside of the dropdown, and the dropdown will close properly (just like it already does, even without this fix, in non-iOS touchscreen devices/browsers, like Chrome/Android and Windows on a touch laptop). This approach, though a bit hacky, has no impact on the DOM structure, and has no unforeseen side effects on touch-enabled laptops/desktops. And crucially, it works just fine in iOS. * Remove dropdown backdrop styles * Update doc for dropdowns and touch-enabled devices
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{% callout info %}
On touch-enabled devices, opening a dropdown adds empty (`$.noop`) `mouseover` handlers to the immediate children of the `<body>` element. This admittedly ugly hack is necessary to work around a [quirk in iOS' event delegation](https://www.quirksmode.org/blog/archives/2014/02/mouse_event_bub.html), which would otherwise prevent a tap anywhere outside of the dropdown from triggering the code that closes the dropdown. Once the dropdown is closed, these additional empty `mouseover` handlers are removed.
{% endcallout %}
### Via data attributes
Add `data-toggle="dropdown"` to a link or button to toggle a dropdown.
{% highlight html %}
<div class="dropdown">
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<button id="dLabel" type="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
Dropdown trigger
</button>
<div class="dropdown-menu" aria-labelledby="dLabel">
...
</div>
</div>
{% endhighlight %}
### Via JavaScript
Call the dropdowns via JavaScript:
{% highlight js %}
$('.dropdown-toggle').dropdown()
{% endhighlight %}
{% callout info %}
##### `data-toggle="dropdown"` still required
Regardless of whether you call your dropdown via JavaScript or instead use the data-api, `data-toggle="dropdown"` is always required to be present on the dropdown's trigger element.
{% endcallout %}
### Options
Options can be passed via data attributes or JavaScript. For data attributes, append the option name to `data-`, as in `data-offset=""`.
<table class="table table-bordered table-striped table-responsive">
<thead>
<tr>
<th style="width: 100px;">Name</th>
<th style="width: 100px;">Type</th>
<th style="width: 50px;">Default</th>
<th>Description</th>
</tr>
</thead>
<tbody>
<tr>
<td>offset</td>
<td>number | string | function</td>
<td>0</td>
<td>Offset of the dropdown relative to its target. For more information refer to Popper.js's <a href="https://popper.js.org/popper-documentation.html#modifiers..offset.offset">offset docs</a>.</td>
</tr>
<tr>
<td>flip</td>
<td>boolean</td>
<td>true</td>
<td>Allow Dropdown to flip in case of an overlapping on the reference element. For more information refer to Popper.js's <a href="https://popper.js.org/popper-documentation.html#modifiers..flip.enabled">flip docs</a>.</td>
</tr>
<tr>
<td>boundary</td>
<td>string | element</td>
<td>'scrollParent'</td>
<td>Overflow constraint boundary of the dropdown menu. Accepts the values of <code>'viewport'</code>, <code>'window'</code>, <code>'scrollParent'</code>, or an HTMLElement reference (JavaScript only). For more information refer to Popper.js's <a href="https://popper.js.org/popper-documentation.html#modifiers..preventOverflow.boundariesElement">preventOverflow docs</a>.</td>
</tr>
</tbody>
</table>
Note when `boundary` is set to any value other than `'scrollParent'`, the style `position: static` is applied to the `.dropdown` container.
### Methods
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| Method | Description |
| --- | --- |
| `$().dropdown('toggle')` | Toggles the dropdown menu of a given navbar or tabbed navigation. |
| `$().dropdown('update')` | Updates the position of an element's dropdown. |
| `$().dropdown('dispose')` | Destroys an element's dropdown. |
### Events
All dropdown events are fired at the `.dropdown-menu`'s parent element and have a `relatedTarget` property, whose value is the toggling anchor element.
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| Event | Description |
| --- | --- |
| `show.bs.dropdown` | This event fires immediately when the show instance method is called. |
| `shown.bs.dropdown` | This event is fired when the dropdown has been made visible to the user (will wait for CSS transitions, to complete). |
| `hide.bs.dropdown` | This event is fired immediately when the hide instance method has been called. |
| `hidden.bs.dropdown`| This event is fired when the dropdown has finished being hidden from the user (will wait for CSS transitions, to complete). |
{% highlight js %}
$('#myDropdown').on('show.bs.dropdown', function () {
// do something…
})
{% endhighlight %}