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Bootstrap/site/content/docs/4.3/components/carousel.md
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carousel.md: Remove duplicate bd-example div. (#29341)
The example shortcode already adds this.
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---
layout: docs
title: Carousel
description: A slideshow component for cycling through elements—images or slides of text—like a carousel.
group: components
toc: true
---
## How it works
The carousel is a slideshow for cycling through a series of content, built with CSS 3D transforms and a bit of JavaScript. It works with a series of images, text, or custom markup. It also includes support for previous/next controls and indicators.
In browsers where the [Page Visibility API](https://www.w3.org/TR/page-visibility/) is supported, the carousel will avoid sliding when the webpage is not visible to the user (such as when the browser tab is inactive, the browser window is minimized, etc.).
{{< callout info >}}
{{< partial "callout-info-prefersreducedmotion.md" >}}
{{< /callout >}}
Please be aware that nested carousels are not supported, and carousels are generally not compliant with accessibility standards.
## Example
Carousels don't automatically normalize slide dimensions. As such, you may need to use additional utilities or custom styles to appropriately size content. While carousels support previous/next controls and indicators, they're not explicitly required. Add and customize as you see fit.
**The `.active` class needs to be added to one of the slides** otherwise the carousel will not be visible. Also be sure to set a unique id on the `.carousel` for optional controls, especially if you're using multiple carousels on a single page. Control and indicator elements must have a `data-target` attribute (or `href` for links) that matches the id of the `.carousel` element.
### Slides only
Here's a carousel with slides only. Note the presence of the `.d-block` and `.w-100` on carousel images to prevent browser default image alignment.
{{< example >}}
<div id="carouselExampleSlidesOnly" class="carousel slide" data-ride="carousel">
<div class="carousel-inner">
<div class="carousel-item active">
{{< placeholder width="800" height="400" class="bd-placeholder-img-lg d-block w-100" color="#555" background="#777" text="First slide" >}}
</div>
<div class="carousel-item">
{{< placeholder width="800" height="400" class="bd-placeholder-img-lg d-block w-100" color="#444" background="#666" text="Second slide" >}}
</div>
<div class="carousel-item">
{{< placeholder width="800" height="400" class="bd-placeholder-img-lg d-block w-100" color="#333" background="#555" text="Third slide" >}}
</div>
</div>
</div>
{{< /example >}}
### With controls
Adding in the previous and next controls:
{{< example >}}
<div id="carouselExampleControls" class="carousel slide" data-ride="carousel">
<div class="carousel-inner">
<div class="carousel-item active">
{{< placeholder width="800" height="400" class="bd-placeholder-img-lg d-block w-100" color="#555" background="#777" text="First slide" >}}
</div>
<div class="carousel-item">
{{< placeholder width="800" height="400" class="bd-placeholder-img-lg d-block w-100" color="#444" background="#666" text="Second slide" >}}
</div>
<div class="carousel-item">
{{< placeholder width="800" height="400" class="bd-placeholder-img-lg d-block w-100" color="#333" background="#555" text="Third slide" >}}
</div>
</div>
<a class="carousel-control-prev" href="#carouselExampleControls" role="button" data-slide="prev">
<span class="carousel-control-prev-icon" aria-hidden="true"></span>
<span class="sr-only">Previous</span>
</a>
<a class="carousel-control-next" href="#carouselExampleControls" role="button" data-slide="next">
<span class="carousel-control-next-icon" aria-hidden="true"></span>
<span class="sr-only">Next</span>
</a>
</div>
{{< /example >}}
### With indicators
You can also add the indicators to the carousel, alongside the controls, too.
{{< example >}}
<div id="carouselExampleIndicators" class="carousel slide" data-ride="carousel">
<ol class="carousel-indicators">
<li data-target="#carouselExampleIndicators" data-slide-to="0" class="active"></li>
<li data-target="#carouselExampleIndicators" data-slide-to="1"></li>
<li data-target="#carouselExampleIndicators" data-slide-to="2"></li>
</ol>
<div class="carousel-inner">
<div class="carousel-item active">
{{< placeholder width="800" height="400" class="bd-placeholder-img-lg d-block w-100" color="#555" background="#777" text="First slide" >}}
</div>
<div class="carousel-item">
{{< placeholder width="800" height="400" class="bd-placeholder-img-lg d-block w-100" color="#444" background="#666" text="Second slide" >}}
</div>
<div class="carousel-item">
{{< placeholder width="800" height="400" class="bd-placeholder-img-lg d-block w-100" color="#333" background="#555" text="Third slide" >}}
</div>
</div>
<a class="carousel-control-prev" href="#carouselExampleIndicators" role="button" data-slide="prev">
<span class="carousel-control-prev-icon" aria-hidden="true"></span>
<span class="sr-only">Previous</span>
</a>
<a class="carousel-control-next" href="#carouselExampleIndicators" role="button" data-slide="next">
<span class="carousel-control-next-icon" aria-hidden="true"></span>
<span class="sr-only">Next</span>
</a>
</div>
{{< /example >}}
### With captions
Add captions to your slides easily with the `.carousel-caption` element within any `.carousel-item`. They can be easily hidden on smaller viewports, as shown below, with optional [display utilities]({{< docsref "/utilities/display" >}}). We hide them initially with `.d-none` and bring them back on medium-sized devices with `.d-md-block`.
{{< example >}}
<div id="carouselExampleCaptions" class="carousel slide" data-ride="carousel">
<ol class="carousel-indicators">
<li data-target="#carouselExampleCaptions" data-slide-to="0" class="active"></li>
<li data-target="#carouselExampleCaptions" data-slide-to="1"></li>
<li data-target="#carouselExampleCaptions" data-slide-to="2"></li>
</ol>
<div class="carousel-inner">
<div class="carousel-item active">
{{< placeholder width="800" height="400" class="bd-placeholder-img-lg d-block w-100" color="#555" background="#777" text="First slide" >}}
<div class="carousel-caption d-none d-md-block">
<h5>First slide label</h5>
<p>Nulla vitae elit libero, a pharetra augue mollis interdum.</p>
</div>
</div>
<div class="carousel-item">
{{< placeholder width="800" height="400" class="bd-placeholder-img-lg d-block w-100" color="#444" background="#666" text="Second slide" >}}
<div class="carousel-caption d-none d-md-block">
<h5>Second slide label</h5>
<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit.</p>
</div>
</div>
<div class="carousel-item">
{{< placeholder width="800" height="400" class="bd-placeholder-img-lg d-block w-100" color="#333" background="#555" text="Third slide" >}}
<div class="carousel-caption d-none d-md-block">
<h5>Third slide label</h5>
<p>Praesent commodo cursus magna, vel scelerisque nisl consectetur.</p>
</div>
</div>
</div>
<a class="carousel-control-prev" href="#carouselExampleCaptions" role="button" data-slide="prev">
<span class="carousel-control-prev-icon" aria-hidden="true"></span>
<span class="sr-only">Previous</span>
</a>
<a class="carousel-control-next" href="#carouselExampleCaptions" role="button" data-slide="next">
<span class="carousel-control-next-icon" aria-hidden="true"></span>
<span class="sr-only">Next</span>
</a>
</div>
{{< /example >}}
### Crossfade
Add `.carousel-fade` to your carousel to animate slides with a fade transition instead of a slide.
{{< example >}}
<div id="carouselExampleFade" class="carousel slide carousel-fade" data-ride="carousel">
<div class="carousel-inner">
<div class="carousel-item active">
{{< placeholder width="800" height="400" class="bd-placeholder-img-lg d-block w-100" color="#555" background="#777" text="First slide" >}}
</div>
<div class="carousel-item">
{{< placeholder width="800" height="400" class="bd-placeholder-img-lg d-block w-100" color="#444" background="#666" text="Second slide" >}}
</div>
<div class="carousel-item">
{{< placeholder width="800" height="400" class="bd-placeholder-img-lg d-block w-100" color="#333" background="#555" text="Third slide" >}}
</div>
</div>
<a class="carousel-control-prev" href="#carouselExampleFade" role="button" data-slide="prev">
<span class="carousel-control-prev-icon" aria-hidden="true"></span>
<span class="sr-only">Previous</span>
</a>
<a class="carousel-control-next" href="#carouselExampleFade" role="button" data-slide="next">
<span class="carousel-control-next-icon" aria-hidden="true"></span>
<span class="sr-only">Next</span>
</a>
</div>
{{< /example >}}
### Individual `.carousel-item` interval
Add `data-interval=""` to a `.carousel-item` to change the amount of time to delay between automatically cycling to the next item.
{{< example >}}
<div id="carouselExampleInterval" class="carousel slide" data-ride="carousel">
<div class="carousel-inner">
<div class="carousel-item active" data-interval="10000">
{{< placeholder width="800" height="400" class="bd-placeholder-img-lg d-block w-100" color="#555" background="#777" text="First slide" >}}
</div>
<div class="carousel-item" data-interval="2000">
{{< placeholder width="800" height="400" class="bd-placeholder-img-lg d-block w-100" color="#444" background="#666" text="Second slide" >}}
</div>
<div class="carousel-item">
{{< placeholder width="800" height="400" class="bd-placeholder-img-lg d-block w-100" color="#333" background="#555" text="Third slide" >}}
</div>
</div>
<a class="carousel-control-prev" href="#carouselExampleInterval" role="button" data-slide="prev">
<span class="carousel-control-prev-icon" aria-hidden="true"></span>
<span class="sr-only">Previous</span>
</a>
<a class="carousel-control-next" href="#carouselExampleInterval" role="button" data-slide="next">
<span class="carousel-control-next-icon" aria-hidden="true"></span>
<span class="sr-only">Next</span>
</a>
</div>
{{< /example >}}
## Usage
### Via data attributes
Use data attributes to easily control the position of the carousel. `data-slide` accepts the keywords `prev` or `next`, which alters the slide position relative to its current position. Alternatively, use `data-slide-to` to pass a raw slide index to the carousel `data-slide-to="2"`, which shifts the slide position to a particular index beginning with `0`.
The `data-ride="carousel"` attribute is used to mark a carousel as animating starting at page load. If you don't use `data-ride="carousel"` to initialize your carousel, you have to initialize it yourself. **It cannot be used in combination with (redundant and unnecessary) explicit JavaScript initialization of the same carousel.**
### Via JavaScript
Call carousel manually with:
{{< highlight js >}}
var myCarousel = document.querySelector('#myCarousel')
var carousel = new bootstrap.Carousel(myCarousel)
{{< /highlight >}}
### Options
Options can be passed via data attributes or JavaScript. For data attributes, append the option name to `data-`, as in `data-interval=""`.
<table class="table">
<thead>
<tr>
<th style="width: 100px;">Name</th>
<th style="width: 50px;">Type</th>
<th style="width: 50px;">Default</th>
<th>Description</th>
</tr>
</thead>
<tbody>
<tr>
<td>interval</td>
<td>number</td>
<td>5000</td>
<td>The amount of time to delay between automatically cycling an item. If false, carousel will not automatically cycle.</td>
</tr>
<tr>
<td>keyboard</td>
<td>boolean</td>
<td>true</td>
<td>Whether the carousel should react to keyboard events.</td>
</tr>
<tr>
<td>pause</td>
<td>string | boolean</td>
<td>"hover"</td>
<td><p>If set to <code>"hover"</code>, pauses the cycling of the carousel on <code>mouseenter</code> and resumes the cycling of the carousel on <code>mouseleave</code>. If set to <code>false</code>, hovering over the carousel won't pause it.</p>
<p>On touch-enabled devices, when set to <code>"hover"</code>, cycling will pause on <code>touchend</code> (once the user finished interacting with the carousel) for two intervals, before automatically resuming. Note that this is in addition to the above mouse behavior.</p></td>
</tr>
<tr>
<td>slide</td>
<td>string | boolean</td>
<td>false</td>
<td>Autoplays the carousel after the user manually cycles the first item. If "carousel", autoplays the carousel on load.</td>
</tr>
<tr>
<td>wrap</td>
<td>boolean</td>
<td>true</td>
<td>Whether the carousel should cycle continuously or have hard stops.</td>
</tr>
<tr>
<td>touch</td>
<td>boolean</td>
<td>true</td>
<td>Whether the carousel should support left/right swipe interactions on touchscreen devices.</td>
</tr>
</tbody>
</table>
### Methods
{{< callout danger >}}
{{< partial "callout-danger-async-methods.md" >}}
{{< /callout >}}
You can create a carousel instance with the carousel constructor, for example, to initialize with additional options and start cycling through items:
{{< highlight js >}}
var myCarousel = document.querySelector('#myCarousel')
var carousel = new bootstrap.Carousel(myCarousel, {
interval: 2000,
wrap: false
})
{{< /highlight >}}
<table class="table">
<thead>
<tr>
<th>Method</th>
<th>Description</th>
</tr>
</thead>
<tbody>
<tr>
<td><code>cycle</code></td>
<td>Cycles through the carousel items from left to right.</td>
</tr>
<tr>
<td><code>pause</code></td>
<td>Stops the carousel from cycling through items.</td>
</tr>
<tr>
<td><code>prev</code></td>
<td>Cycles to the previous item. <strong>Returns to the caller before the previous item has been shown</strong> (e.g., before the <code>slid.bs.carousel</code> event occurs).</td>
</tr>
<tr>
<td><code>next</code></td>
<td>Cycles to the next item. <strong>Returns to the caller before the next item has been shown</strong> (e.g., before the <code>slid.bs.carousel</code> event occurs).</td>
</tr>
<tr>
<td><code>nextWhenVisible</code></td>
<td>Cycles the carousel to a particular frame (0 based, similar to an array). <strong>Returns to the caller before the target item has been shown</strong> (e.g., before the <code>slid.bs.carousel</code> event occurs).</td>
</tr>
<tr>
<td><code>dispose</code></td>
<td>Destroys an element's carousel.</td>
</tr>
<tr>
<td><code>getInstance</code></td>
<td>Static method which allows you to get the carousel instance associated with a DOM element.</td>
</tr>
</tbody>
</table>
### Events
Bootstrap's carousel class exposes two events for hooking into carousel functionality. Both events have the following additional properties:
- `direction`: The direction in which the carousel is sliding (either `"left"` or `"right"`).
- `relatedTarget`: The DOM element that is being slid into place as the active item.
- `from`: The index of the current item
- `to`: The index of the next item
All carousel events are fired at the carousel itself (i.e. at the `<div class="carousel">`).
<table class="table">
<thead>
<tr>
<th style="width: 150px;">Event type</th>
<th>Description</th>
</tr>
</thead>
<tbody>
<tr>
<td><code>slide.bs.carousel</code></td>
<td>Fires immediately when the <code>slide</code> instance method is invoked.</td>
</tr>
<tr>
<td><code>slid.bs.carousel</code></td>
<td>Fired when the carousel has completed its slide transition.</td>
</tr>
</tbody>
</table>
{{< highlight js >}}
var myCarousel = document.getElementById('myCarousel')
myCarousel.addEventListener('slide.bs.carousel', function () {
// do something...
})
{{< /highlight >}}
### Change transition duration
The transition duration of `.carousel-item` can be changed with the `$carousel-transition` Sass variable before compiling or custom styles if you're using the compiled CSS. If multiple transitions are applied, make sure the transform transition is defined first (eg. `transition: transform 2s ease, opacity .5s ease-out`).