0
0
mirror of https://github.com/twbs/bootstrap.git synced 2025-02-19 16:54:24 +01:00

Docs: rewrite/reorganise carousel docs page (#37354)

* Instantiate/initialize all non-autoplaying carousels in docs pages

* Rewrite/reorganise carousel docs page

* start with static/non-autoplaying examples
* explicitly mention that carousels currently need to be manually initialized
* split out and explain autoplaying and the weird "autoplay after first interaction" behaviour, as well as the pause on hover/focus

* Add callout about autoplaying and accessibility

* Don't have the dark variant example autoplay

* Add "autoplaying" to cspell custom dictionary

* Tweal wording, move Page Visibility API to autoplay section

* Tweak explanation for methods, add line break in js code for consistency with last code block on the page

* Tweak method descriptions

* Tweak headings (plural "carousels")

* Move some paragraphs out of intro and into basic example, reword the nested and accessibility paragraph

* Tweak warning about `.active` slide

* Tweak callout wording

* Further prose tweaks

move the sentence about not double-initialising autoplaying carousels to the callout right at the top
instead of talking about `data-bs...` attributes, talk about the "option" instead, as authors may be setting these not via data attributes, but at instatiation time with options in the constructor
remove the incorrect statement about pausing when keyboard focus is in the carousel

* Instantiate/initialize all non-autoplaying carousels in docs pages

* Rewrite/reorganise carousel docs page

* start with static/non-autoplaying examples
* explicitly mention that carousels currently need to be manually initialized
* split out and explain autoplaying and the weird "autoplay after first interaction" behaviour, as well as the pause on hover/focus

* Add callout about autoplaying and accessibility

* Don't have the dark variant example autoplay

* Add "autoplaying" to cspell custom dictionary

* Tweal wording, move Page Visibility API to autoplay section

* Tweak explanation for methods, add line break in js code for consistency with last code block on the page

* Tweak method descriptions

* Tweak headings (plural "carousels")

* Move some paragraphs out of intro and into basic example, reword the nested and accessibility paragraph

* Tweak warning about `.active` slide

* Tweak callout wording

* Further prose tweaks

move the sentence about not double-initialising autoplaying carousels to the callout right at the top
instead of talking about `data-bs...` attributes, talk about the "option" instead, as authors may be setting these not via data attributes, but at instatiation time with options in the constructor
remove the incorrect statement about pausing when keyboard focus is in the carousel

* Fix relative link

* Update site/assets/js/snippets.js

Co-authored-by: GeoSot <geo.sotis@gmail.com>

* Fix snippet.js

* Tweak content organisation just a bit

Co-authored-by: GeoSot <geo.sotis@gmail.com>
Co-authored-by: Julien Déramond <juderamond@gmail.com>
Co-authored-by: Julien Déramond <julien.deramond@orange.com>
Co-authored-by: Mark Otto <markdotto@gmail.com>
This commit is contained in:
Patrick H. Lauke 2022-11-29 07:20:35 +00:00 committed by GitHub
parent 26a3ef1bcb
commit 0444d2cfe5
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
3 changed files with 123 additions and 54 deletions

View File

@ -8,6 +8,7 @@
"autohiding",
"autoplay",
"autoplays",
"autoplaying",
"blazingly",
"Blockquotes",
"Bootstrappers",

View File

@ -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.Carousel.getOrCreateInstance(carousel)
})
// -------------------------------
// Checks & Radios
// -------------------------------

View File

@ -8,28 +8,24 @@ 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.
- 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.).
- 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.
The only exception are [autoplaying carousels](#autoplaying-carousels) with the `data-bs-ride="carousel"` attribute as these are initialized automatically on page load. If you're using autoplaying carousels with the data attribute, **don't explicitly initialize the same carousels with the constructor method.**
- Nested carousels are not supported. You should also be aware that carousels in general can often cause usability and accessibility challenges.
{{< 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.
## Basic examples
## 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-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.
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="carouselExampleSlidesOnly" 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" >}}
@ -41,43 +37,27 @@ Here's a carousel with slides only. Note the presence of the `.d-block` and `.w-
{{< 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. 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 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="#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 can also add the indicators to the carousel, alongside the controls, too.
**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.
### 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 +85,12 @@ 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 +135,7 @@ 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 +158,66 @@ 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`. 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).
{{< 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 >}}
{{< 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 +246,29 @@ Add `data-bs-interval=""` to a `.carousel-item` to change the amount of time to
</div>
{{< /example >}}
### Disable touch swiping
### Autoplaying carousels without controls
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.
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 by setting the `touch` option to `false`.
{{< example >}}
<div id="carouselExampleControlsNoTouching" class="carousel slide" data-bs-touch="false">
@ -238,12 +298,12 @@ Carousels support swiping left/right on touchscreen devices to move between slid
{{< deprecated-in "5.3.0" >}}
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`.
{{< callout-deprecated-dark-variants "carousel" >}}
{{< 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>
@ -305,8 +365,6 @@ 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:
@ -338,25 +396,26 @@ 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). |