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| -rw-r--r-- | .cspell.json | 1 | ||||
| -rw-r--r-- | site/assets/js/snippets.js | 9 | ||||
| -rw-r--r-- | site/content/docs/5.2/components/carousel.md | 169 |
3 files changed, 128 insertions, 51 deletions
diff --git a/.cspell.json b/.cspell.json index d528823b1d..752acd5218 100644 --- a/.cspell.json +++ b/.cspell.json @@ -8,6 +8,7 @@ "autohiding", "autoplay", "autoplays", + "autoplaying", "blazingly", "Blockquotes", "Bootstrappers", diff --git a/site/assets/js/snippets.js b/site/assets/js/snippets.js index 53f8a786ec..e5f084f65b 100644 --- a/site/assets/js/snippets.js +++ b/site/assets/js/snippets.js @@ -96,6 +96,15 @@ }) } + // -------- + // Carousels + // -------- + // Instantiate all non-autoplaying carousels in a docs or StackBlitz page + document.querySelectorAll('.carousel:not([data-bs-ride="carousel"])') + .forEach(carousel => { + bootstrap.getOrCreateInstance.Carousel(carousel) + }) + // ------------------------------- // Checks & Radios // ------------------------------- diff --git a/site/content/docs/5.2/components/carousel.md b/site/content/docs/5.2/components/carousel.md index 376998298f..1ce1e88d2c 100644 --- a/site/content/docs/5.2/components/carousel.md +++ b/site/content/docs/5.2/components/carousel.md @@ -10,46 +10,24 @@ toc: true 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 "callouts/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. +Note that nested carousels are not supported. You should also be aware that carousels can often cause usability and accessibility challenges. -**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-bs-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. +{{< callout warning >}} +For performance reasons, carousels must be manually initialized using the [carousel constructor method](#methods). Without initialization, some of the event listeners (specifically, the events needed touch/swipe support) will not be registered until a user has explicitly activated a control or indicator. -{{< example >}} -<div id="carouselExampleSlidesOnly" class="carousel slide" data-bs-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 >}} +The only exception are [autoplaying carousels](#autoplaying-carousels) with the `data-bs-ride="carousel"` attribute – these are initialized automatically on page load. If you are using autoplaying carousels with the data attribute, **don't explicitly initialize the same carousels with the constructor method.** +{{< /callout >}} -### With controls +## Basic examples -Adding in the previous and next controls. We recommend using `<button>` elements, but you can also use `<a>` elements with `role="button"`. +Here is a basic example of a carousel with three slides. Note the previous/next controls. We recommend using `<button>` elements, but you can also use `<a>` elements with `role="button"`. {{< example >}} -<div id="carouselExampleControls" class="carousel slide" data-bs-ride="carousel"> +<div id="carouselExample" class="carousel slide"> <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" >}} @@ -61,23 +39,27 @@ Adding in the previous and next controls. We recommend using `<button>` elements {{< placeholder width="800" height="400" class="bd-placeholder-img-lg d-block w-100" color="#333" background="#555" text="Third slide" >}} </div> </div> - <button class="carousel-control-prev" type="button" data-bs-target="#carouselExampleControls" data-bs-slide="prev"> + <button class="carousel-control-prev" type="button" data-bs-target="#carouselExample" data-bs-slide="prev"> <span class="carousel-control-prev-icon" aria-hidden="true"></span> <span class="visually-hidden">Previous</span> </button> - <button class="carousel-control-next" type="button" data-bs-target="#carouselExampleControls" data-bs-slide="next"> + <button class="carousel-control-next" type="button" data-bs-target="#carouselExample" data-bs-slide="next"> <span class="carousel-control-next-icon" aria-hidden="true"></span> <span class="visually-hidden">Next</span> </button> </div> {{< /example >}} -### With indicators +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. + +**You must add the `.active` class 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-bs-target` attribute (or `href` for links) that matches the `id` of the `.carousel` element. -You can also add the indicators to the carousel, alongside the controls, too. +### Indicators + +You can add indicators to the carousel, alongside the previous/next controls. The indicators let users jump directly to a particular slide. {{< example >}} -<div id="carouselExampleIndicators" class="carousel slide" data-bs-ride="true"> +<div id="carouselExampleIndicators" class="carousel slide"> <div class="carousel-indicators"> <button type="button" data-bs-target="#carouselExampleIndicators" data-bs-slide-to="0" class="active" aria-current="true" aria-label="Slide 1"></button> <button type="button" data-bs-target="#carouselExampleIndicators" data-bs-slide-to="1" aria-label="Slide 2"></button> @@ -105,12 +87,12 @@ You can also add the indicators to the carousel, alongside the controls, too. </div> {{< /example >}} -### With captions +### 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`. +You can add captions to your slides 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-bs-ride="false"> +<div id="carouselExampleCaptions" class="carousel slide"> <div class="carousel-indicators"> <button type="button" data-bs-target="#carouselExampleCaptions" data-bs-slide-to="0" class="active" aria-current="true" aria-label="Slide 1"></button> <button type="button" data-bs-target="#carouselExampleCaptions" data-bs-slide-to="1" aria-label="Slide 2"></button> @@ -155,7 +137,7 @@ Add captions to your slides easily with the `.carousel-caption` element within a Add `.carousel-fade` to your carousel to animate slides with a fade transition instead of a slide. Depending on your carousel content (e.g., text only slides), you may want to add `.bg-body` or some custom CSS to the `.carousel-item`s for proper crossfading. {{< example >}} -<div id="carouselExampleFade" class="carousel slide carousel-fade" data-bs-ride="carousel"> +<div id="carouselExampleFade" class="carousel slide carousel-fade"> <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" >}} @@ -178,6 +160,72 @@ Add `.carousel-fade` to your carousel to animate slides with a fade transition i </div> {{< /example >}} +## Autoplaying carousels + +You can make your carousels autoplay on page load by setting the `ride` option to `carousel`. + +{{< callout info >}} +For accessibility reasons, we recommend avoiding the use of autoplaying carousels. + +If your page does include an autoplaying carousel, we recommend providing an additional button or control to explicitly pause/stop the carousel. + +See [WCAG 2.1 Success Criterion 2.2.2 Pause, Stop, Hide](https://www.w3.org/TR/WCAG21/#pause-stop-hide). +{{< /callout >}} + +Autoplaying carousels automatically pause while hovered with the mouse. This behavior can be controlled with the `pause` option. + +In browsers that support the [Page Visibility API](https://www.w3.org/TR/page-visibility/), the carousel will stop cycling when the webpage is not visible to the user (such as when the browser tab is inactive, or when the browser window is minimized). + +{{< example >}} +<div id="carouselExampleAutoplaying" class="carousel slide" data-bs-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> + <button class="carousel-control-prev" type="button" data-bs-target="#carouselExampleAutoplaying" data-bs-slide="prev"> + <span class="carousel-control-prev-icon" aria-hidden="true"></span> + <span class="visually-hidden">Previous</span> + </button> + <button class="carousel-control-next" type="button" data-bs-target="#carouselExampleAutoplaying" data-bs-slide="next"> + <span class="carousel-control-next-icon" aria-hidden="true"></span> + <span class="visually-hidden">Next</span> + </button> +</div> +{{< /example >}} + +When the `ride` option is set to `true`, rather than `carousel`, the carousel won't automatically start to cycle on page load. Instead, it will only start after the first user interaction. + +{{< example >}} +<div id="carouselExampleRide" class="carousel slide" data-bs-ride="true"> + <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> + <button class="carousel-control-prev" type="button" data-bs-target="#carouselExampleRide" data-bs-slide="prev"> + <span class="carousel-control-prev-icon" aria-hidden="true"></span> + <span class="visually-hidden">Previous</span> + </button> + <button class="carousel-control-next" type="button" data-bs-target="#carouselExampleRide" data-bs-slide="next"> + <span class="carousel-control-next-icon" aria-hidden="true"></span> + <span class="visually-hidden">Next</span> + </button> +</div> +{{< /example >}} + ### Individual `.carousel-item` interval Add `data-bs-interval=""` to a `.carousel-item` to change the amount of time to delay between automatically cycling to the next item. @@ -206,9 +254,29 @@ Add `data-bs-interval=""` to a `.carousel-item` to change the amount of time to </div> {{< /example >}} -### Disable touch swiping +### Autoplaying carousels without controls + +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-bs-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 >}} + +## Disable touch swiping -Carousels support swiping left/right on touchscreen devices to move between slides. This can be disabled using the `data-bs-touch` attribute. The example below also does not include the `data-bs-ride` attribute so it doesn't autoplay. +Carousels support swiping left/right on touchscreen devices to move between slides. This can be disabled by setting the `touch` option to `false`. {{< example >}} <div id="carouselExampleControlsNoTouching" class="carousel slide" data-bs-touch="false"> @@ -236,10 +304,10 @@ Carousels support swiping left/right on touchscreen devices to move between slid ## Dark variant -Add `.carousel-dark` to the `.carousel` for darker controls, indicators, and captions. Controls have been inverted from their default white fill with the `filter` CSS property. Captions and controls have additional Sass variables that customize the `color` and `background-color`. +Add `.carousel-dark` to the `.carousel` for darker controls, indicators, and captions. Controls are inverted compared to their default white fill with the `filter` CSS property. Captions and controls have additional Sass variables that customize the `color` and `background-color`. {{< example >}} -<div id="carouselExampleDark" class="carousel carousel-dark slide" data-bs-ride="carousel"> +<div id="carouselExampleDark" class="carousel carousel-dark slide"> <div class="carousel-indicators"> <button type="button" data-bs-target="#carouselExampleDark" data-bs-slide-to="0" class="active" aria-current="true" aria-label="Slide 1"></button> <button type="button" data-bs-target="#carouselExampleDark" data-bs-slide-to="1" aria-label="Slide 2"></button> @@ -301,8 +369,6 @@ Variables for the [dark carousel](#dark-variant): Use data attributes to easily control the position of the carousel. `data-bs-slide` accepts the keywords `prev` or `next`, which alters the slide position relative to its current position. Alternatively, use `data-bs-slide-to` to pass a raw slide index to the carousel `data-bs-slide-to="2"`, which shifts the slide position to a particular index beginning with `0`. -The `data-bs-ride="carousel"` attribute is used to mark a carousel as animating starting at page load. If you don't use `data-bs-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: @@ -334,25 +400,26 @@ const carousel = new bootstrap.Carousel('#myCarousel') {{< partial "callouts/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: +You can create a carousel instance with the carousel constructor, and pass on any additional options. For example, to manually initialize an autoplaying carousel (assuming you're not using the `data-bs-ride="carousel"` attribute in the markup itself) with a specific interval and with touch support disabled, you can use: ```js const myCarouselElement = document.querySelector('#myCarousel') + const carousel = new bootstrap.Carousel(myCarouselElement, { interval: 2000, - wrap: false + touch: false }) ``` {{< bs-table >}} | Method | Description | | --- | --- | -| `cycle` | Cycles through the carousel items from left to right. | +| `cycle` | Starts cycling through the carousel items from left to right. | | `dispose` | Destroys an element's carousel. (Removes stored data on the DOM element) | -| `getInstance` | Static method which allows you to get the carousel instance associated to a DOM element, you can use it like this: `bootstrap.Carousel.getInstance(element)`. | -| `getOrCreateInstance` | Static method which returns a carousel instance associated to a DOM element or create a new one in case it wasn't initialized. You can use it like this: `bootstrap.Carousel.getOrCreateInstance(element)`. | +| `getInstance` | Static method which allows you to get the carousel instance associated to a DOM element. You can use it like this: `bootstrap.Carousel.getInstance(element)`. | +| `getOrCreateInstance` | Static method which returns a carousel instance associated to a DOM element, or creates a new one in case it wasn't initialized. You can use it like this: `bootstrap.Carousel.getOrCreateInstance(element)`. | | `next` | Cycles to the next item. **Returns to the caller before the next item has been shown** (e.g., before the `slid.bs.carousel` event occurs). | -| `nextWhenVisible` | Don't cycle carousel to next when the page isn't visible or the carousel or its parent isn't visible. **Returns to the caller before the target item has been shown**. | +| `nextWhenVisible` | Don't cycle carousel to next when the page, the carousel, or the carousel's parent aren't visible. **Returns to the caller before the target item has been shown**. | | `pause` | Stops the carousel from cycling through items. | | `prev` | Cycles to the previous item. **Returns to the caller before the previous item has been shown** (e.g., before the `slid.bs.carousel` event occurs). | | `to` | Cycles the carousel to a particular frame (0 based, similar to an array). **Returns to the caller before the target item has been shown** (e.g., before the `slid.bs.carousel` event occurs). | |