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diff --git a/vendor/twbs/bootstrap/site/docs/4.3/components/dropdowns.md b/vendor/twbs/bootstrap/site/docs/4.3/components/dropdowns.md new file mode 100644 index 000000000..417d9f5ea --- /dev/null +++ b/vendor/twbs/bootstrap/site/docs/4.3/components/dropdowns.md @@ -0,0 +1,909 @@ +--- +layout: docs +title: Dropdowns +description: Toggle contextual overlays for displaying lists of links and more with the Bootstrap dropdown plugin. +group: components +toc: true +--- + +## Overview + +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). + +## 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/WAI/PF/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. + +## 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 + +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: + +{% capture example %} +<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 + </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> +{% endcapture %} +{% include example.html content=example %} + +And with `<a>` elements: + +{% capture example %} +<div class="dropdown"> + <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> +</div> +{% endcapture %} +{% include example.html content=example %} + +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 + +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 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"> + ... + </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 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"> + ... + </div> +</div> +{% endhighlight %} + +## Directions + +### Dropup + +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"> + 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 dropdown-toggle-split" 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 + +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 Dropright</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 dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false"> + Dropright + </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 dropdown-toggle-split" 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 + +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. + +{% capture example %} +<div class="dropdown"> + <button class="btn btn-secondary dropdown-toggle" type="button" id="dropdownMenu2" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false"> + Dropdown + </button> + <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> +{% endcapture %} +{% include example.html content=example %} + +You can also create non-interactive dropdown items with `.dropdown-item-text`. Feel free to style further with custom CSS or text utilities. + +{% capture example %} +<div class="dropdown-menu"> + <span class="dropdown-item-text">Dropdown item text</span> + <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> +{% endcapture %} +{% include example.html content=example %} + +### Active + +Add `.active` to items in the dropdown to **style them as active**. + +{% capture example %} +<div class="dropdown-menu"> + <a class="dropdown-item" href="#">Regular link</a> + <a class="dropdown-item active" href="#">Active link</a> + <a class="dropdown-item" href="#">Another link</a> +</div> +{% endcapture %} +{% include example.html content=example %} + +### Disabled + +Add `.disabled` to items in the dropdown to **style them as disabled**. + +{% capture example %} +<div class="dropdown-menu"> + <a class="dropdown-item" href="#">Regular link</a> + <a class="dropdown-item disabled" href="#" tabindex="-1" aria-disabled="true">Disabled link</a> + <a class="dropdown-item" href="#">Another link</a> +</div> +{% endcapture %} +{% include example.html content=example %} + +## Menu 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. + +{% capture callout %} +**Heads up!** Dropdowns are positioned thanks to Popper.js (except when they are contained in a navbar). +{% endcapture %} +{% include callout.html content=callout type="info" %} + +{% capture example %} +<div class="btn-group"> + <button type="button" class="btn btn-secondary dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false"> + Right-aligned menu + </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> +{% endcapture %} +{% include example.html content=example %} + +### Responsive alignment + +If you want to use responsive alignment, disable dynamic positioning by adding the `data-display="static"` attribute and use the responsive variation classes. + +To align **right** the dropdown menu with the given breakpoint or larger, add `.dropdown-menu{-sm|-md|-lg|-xl}-right`. + +{% capture example %} +<div class="btn-group"> + <button type="button" class="btn btn-secondary dropdown-toggle" data-toggle="dropdown" data-display="static" aria-haspopup="true" aria-expanded="false"> + Left-aligned but right aligned when large screen + </button> + <div class="dropdown-menu dropdown-menu-lg-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> +{% endcapture %} +{% include example.html content=example %} + +To align **left** the dropdown menu with the given breakpoint or larger, add `.dropdown-menu-right` and `.dropdown-menu{-sm|-md|-lg|-xl}-left`. + +{% capture example %} +<div class="btn-group"> + <button type="button" class="btn btn-secondary dropdown-toggle" data-toggle="dropdown" data-display="static" aria-haspopup="true" aria-expanded="false"> + Right-aligned but left aligned when large screen + </button> + <div class="dropdown-menu dropdown-menu-right dropdown-menu-lg-left"> + <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> +{% endcapture %} +{% include example.html content=example %} + +Note that you don't need to add a `data-display="static"` attribute to dropdown buttons in navbars, since Popper.js isn't used in navbars. + +## Menu content + +### Headers + +Add a header to label sections of actions in any dropdown menu. + +{% capture example %} +<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> +{% endcapture %} +{% include example.html content=example %} + +### Dividers + +Separate groups of related menu items with a divider. + +{% capture example %} +<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> +{% endcapture %} +{% include example.html content=example %} + +### Text + +Place any freeform text within a dropdown menu with text and use [spacing utilities]({{ site.baseurl }}/docs/{{ site.docs_version }}/utilities/spacing/). Note that you'll likely need additional sizing styles to constrain the menu width. + +{% capture example %} +<div class="dropdown-menu p-4 text-muted" style="max-width: 200px;"> + <p> + Some example text that's free-flowing within the dropdown menu. + </p> + <p class="mb-0"> + And this is more example text. + </p> +</div> +{% endcapture %} +{% include example.html content=example %} + +### 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. + +{% capture example %} +<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-group"> + <div class="form-check"> + <input type="checkbox" class="form-check-input" id="dropdownCheck"> + <label class="form-check-label" for="dropdownCheck"> + Remember me + </label> + </div> + </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> +{% endcapture %} +{% include example.html content=example %} + +{% capture example %} +<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"> + <label for="exampleDropdownFormPassword2">Password</label> + <input type="password" class="form-control" id="exampleDropdownFormPassword2" placeholder="Password"> + </div> + <div class="form-group"> + <div class="form-check"> + <input type="checkbox" class="form-check-input" id="dropdownCheck2"> + <label class="form-check-label" for="dropdownCheck2"> + Remember me + </label> + </div> + </div> + <button type="submit" class="btn btn-primary">Sign in</button> +</form> +{% endcapture %} +{% include example.html content=example %} + +## Dropdown options + +Use `data-offset` or `data-reference` to change the location of the dropdown. + +{% capture example %} +<div class="d-flex"> + <div class="dropdown mr-1"> + <button type="button" class="btn btn-secondary dropdown-toggle" id="dropdownMenuOffset" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false" data-offset="10,20"> + Offset + </button> + <div class="dropdown-menu" aria-labelledby="dropdownMenuOffset"> + <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> + <div class="btn-group"> + <button type="button" class="btn btn-secondary">Reference</button> + <button type="button" class="btn btn-secondary dropdown-toggle dropdown-toggle-split" id="dropdownMenuReference" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false" data-reference="parent"> + <span class="sr-only">Toggle Dropdown</span> + </button> + <div class="dropdown-menu" aria-labelledby="dropdownMenuReference"> + <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> +{% endcapture %} +{% include example.html content=example %} + +## Usage + +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. + +{% capture callout %} +On touch-enabled devices, opening a dropdown adds empty (`$.noop`) `mouseover` handlers to the immediate children of the `<body>` element. This admittedly ugly hack is necessary to work around a [quirk in iOS' event delegation](https://www.quirksmode.org/blog/archives/2014/02/mouse_event_bub.html), which would otherwise prevent a tap anywhere outside of the dropdown from triggering the code that closes the dropdown. Once the dropdown is closed, these additional empty `mouseover` handlers are removed. +{% endcapture %} +{% include callout.html content=callout type="info" %} + +### Via data attributes + +Add `data-toggle="dropdown"` to a link or button to toggle a dropdown. + +{% highlight html %} +<div class="dropdown"> + <button id="dLabel" type="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false"> + Dropdown trigger + </button> + <div class="dropdown-menu" aria-labelledby="dLabel"> + ... + </div> +</div> +{% endhighlight %} + +### Via JavaScript + +Call the dropdowns via JavaScript: + +{% highlight js %} +$('.dropdown-toggle').dropdown() +{% endhighlight %} + +{% capture callout %} +##### `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. +{% endcapture %} +{% include callout.html content=callout type="info" %} + +### 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"> + <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> + <p>Offset of the dropdown relative to its target.</p> + <p>When a function is used to determine the offset, it is called with an object containing the offset data as its first argument. The function must return an object with the same structure. The triggering element DOM node is passed as the second argument.</p> + <p>For more information refer to Popper.js's <a href="https://popper.js.org/popper-documentation.html#modifiers..offset.offset">offset docs</a>.</p> + </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> + <tr> + <td>reference</td> + <td>string | element</td> + <td>'toggle'</td> + <td>Reference element of the dropdown menu. Accepts the values of <code>'toggle'</code>, <code>'parent'</code>, or an HTMLElement reference. For more information refer to Popper.js's <a href="https://popper.js.org/popper-documentation.html#referenceObject">referenceObject docs</a>.</td> + </tr> + <tr> + <td>display</td> + <td>string</td> + <td>'dynamic'</td> + <td>By default, we use Popper.js for dynamic positioning. Disable this with <code>static</code>.</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 + +| Method | Description | +| --- | --- | +| `$().dropdown('toggle')` | Toggles the dropdown menu of a given navbar or tabbed navigation. | +| `$().dropdown('show')` | Shows the dropdown menu of a given navbar or tabbed navigation. | +| `$().dropdown('hide')` | Hides the dropdown menu of a given navbar or tabbed navigation. | +| `$().dropdown('update')` | Updates the position of an element's dropdown. | +| `$().dropdown('dispose')` | Destroys an element's dropdown. | + +### Events + +All dropdown events are fired at the `.dropdown-menu`'s parent element and have a `relatedTarget` property, whose value is the toggling anchor element. +`hide.bs.dropdown` and `hidden.bs.dropdown` events have a `clickEvent` property (only when the original event type is `click`) that contains an Event Object for the click event. + +| Event | Description | +| --- | --- | +| `show.bs.dropdown` | This event fires immediately when the show instance method is called. | +| `shown.bs.dropdown` | This event is fired when the dropdown has been made visible to the user (will wait for CSS transitions, to complete). | +| `hide.bs.dropdown` | This event is fired immediately when the hide instance method has been called. | +| `hidden.bs.dropdown`| This event is fired when the dropdown has finished being hidden from the user (will wait for CSS transitions, to complete). | + +{% highlight js %} +$('#myDropdown').on('show.bs.dropdown', function () { + // do something... +}) +{% endhighlight %} |