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Bootstrap/site/content/docs/5.2/components/offcanvas.md
Louis-Maxime Piton 8959bf3f0b
Docs: quick fixes for HTML (#36395) 
* Using the new helper in the doc

* Remove input from `Tab` access

* Change scrollspy code examples

* Reordering tables for JS

* Fix for parcel file

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* Alphabetical reorder the helpers
2022-05-20 10:21:48 -07:00

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docs Offcanvas Build hidden sidebars into your project for navigation, shopping carts, and more with a few classes and our JavaScript plugin. components true

How it works

Offcanvas is a sidebar component that can be toggled via JavaScript to appear from the left, right, top, or bottom edge of the viewport. Buttons or anchors are used as triggers that are attached to specific elements you toggle, and data attributes are used to invoke our JavaScript.

  • Offcanvas shares some of the same JavaScript code as modals. Conceptually, they are quite similar, but they are separate plugins.
  • Similarly, some source Sass variables for offcanvas's styles and dimensions are inherited from the modal's variables.
  • When shown, offcanvas includes a default backdrop that can be clicked to hide the offcanvas.
  • Similar to modals, only one offcanvas can be shown at a time.

Heads up! Given how CSS handles animations, you cannot use margin or translate on an .offcanvas element. Instead, use the class as an independent wrapping element.

{{< callout info >}} {{< partial "callout-info-prefersreducedmotion.md" >}} {{< /callout >}}

Examples

Offcanvas components

Below is an offcanvas example that is shown by default (via .show on .offcanvas). Offcanvas includes support for a header with a close button and an optional body class for some initial padding. We suggest that you include offcanvas headers with dismiss actions whenever possible, or provide an explicit dismiss action.

{{< example class="bd-example-offcanvas p-0 bg-light overflow-hidden" >}}

Offcanvas
Content for the offcanvas goes here. You can place just about any Bootstrap component or custom elements here.
{{< /example >}}

Live demo

Use the buttons below to show and hide an offcanvas element via JavaScript that toggles the .show class on an element with the .offcanvas class.

  • .offcanvas hides content (default)
  • .offcanvas.show shows content

You can use a link with the href attribute, or a button with the data-bs-target attribute. In both cases, the data-bs-toggle="offcanvas" is required.

{{< example >}} Link with href Button with data-bs-target

Offcanvas
Some text as placeholder. In real life you can have the elements you have chosen. Like, text, images, lists, etc.
{{< /example >}}

Body scrolling

Scrolling the <body> element is disabled when an offcanvas and its backdrop are visible. Use the data-bs-scroll attribute to enable <body> scrolling.

{{< example >}} Enable body scrolling

Offcanvas with body scrolling

Try scrolling the rest of the page to see this option in action.

{{< /example >}}

Body scrolling and backdrop

You can also enable <body> scrolling with a visible backdrop.

{{< example >}} Enable both scrolling & backdrop

Backdrop with scrolling

Try scrolling the rest of the page to see this option in action.

{{< /example >}}

Static backdrop

When backdrop is set to static, the offcanvas will not close when clicking outside of it.

{{< example >}} Toggle static offcanvas

Offcanvas
I will not close if you click outside of me.
{{< /example >}}

Responsive

Added in v5.2.0

Responsive offcanvas classes hide content outside the viewport from a specified breakpoint and down. Above that breakpoint, the contents within will behave as usual. For example, .offcanvas-lg hides content in an offcanvas below the lg breakpoint, but shows the content above the lg breakpoint.

{{< example >}} Toggle offcanvas

Resize your browser to show the responsive offcanvas toggle.
Responsive offcanvas

This is content within an .offcanvas-lg.

{{< /example >}}

Responsive offcanvas classes are available across for each breakpoint.

  • .offcanvas
  • .offcanvas-sm
  • .offcanvas-md
  • .offcanvas-lg
  • .offcanvas-xl
  • .offcanvas-xxl

Placement

There's no default placement for offcanvas components, so you must add one of the modifier classes below.

  • .offcanvas-start places offcanvas on the left of the viewport (shown above)
  • .offcanvas-end places offcanvas on the right of the viewport
  • .offcanvas-top places offcanvas on the top of the viewport
  • .offcanvas-bottom places offcanvas on the bottom of the viewport

Try the top, right, and bottom examples out below.

{{< example >}} Toggle top offcanvas

Offcanvas top
...
{{< /example >}}

{{< example >}} Toggle right offcanvas

Offcanvas right
...
{{< /example >}}

{{< example >}} Toggle bottom offcanvas

Offcanvas bottom
...
{{< /example >}}

Accessibility

Since the offcanvas panel is conceptually a modal dialog, be sure to add aria-labelledby="..."—referencing the offcanvas title—to .offcanvas. Note that you don’t need to add role="dialog" since we already add it via JavaScript.

CSS

Variables

Added in v5.2.0

As part of Bootstrap's evolving CSS variables approach, offcanvas now uses local CSS variables on .offcanvas for enhanced real-time customization. Values for the CSS variables are set via Sass, so Sass customization is still supported, too.

{{< scss-docs name="offcanvas-css-vars" file="scss/_offcanvas.scss" >}}

Sass variables

{{< scss-docs name="offcanvas-variables" file="scss/_variables.scss" >}}

Usage

The offcanvas plugin utilizes a few classes and attributes to handle the heavy lifting:

  • .offcanvas hides the content
  • .offcanvas.show shows the content
  • .offcanvas-start hides the offcanvas on the left
  • .offcanvas-end hides the offcanvas on the right
  • .offcanvas-top hides the offcanvas on the top
  • .offcanvas-bottom hides the offcanvas on the bottom

Add a dismiss button with the data-bs-dismiss="offcanvas" attribute, which triggers the JavaScript functionality. Be sure to use the <button> element with it for proper behavior across all devices.

Via data attributes

Toggle

Add data-bs-toggle="offcanvas" and a data-bs-target or href to the element to automatically assign control of one offcanvas element. The data-bs-target attribute accepts a CSS selector to apply the offcanvas to. Be sure to add the class offcanvas to the offcanvas element. If you'd like it to default open, add the additional class show.

Dismiss

{{% js-dismiss "offcanvas" %}}

{{< callout warning >}} While both ways to dismiss an offcanvas are supported, keep in mind that dismissing from outside an offcanvas does not match the WAI-ARIA modal dialog design pattern. Do this at your own risk. {{< /callout >}}

Via JavaScript

Enable manually with:

const offcanvasElementList = document.querySelectorAll('.offcanvas')
const offcanvasList = [...offcanvasElementList].map(offcanvasEl => new bootstrap.Offcanvas(offcanvasEl))

Options

{{< markdown >}} {{< partial "js-data-attributes.md" >}} {{< /markdown >}}

{{< bs-table "table" >}}

Name Type Default Description
backdrop boolean or the string static true Apply a backdrop on body while offcanvas is open. Alternatively, specify static for a backdrop which doesn't close the offcanvas when clicked.
keyboard boolean true Closes the offcanvas when escape key is pressed
scroll boolean false Allow body scrolling while offcanvas is open
{{< /bs-table >}}

Methods

{{< callout danger >}} {{< partial "callout-danger-async-methods.md" >}} {{< /callout >}}

Activates your content as an offcanvas element. Accepts an optional options object.

You can create an offcanvas instance with the constructor, for example:

const bsOffcanvas = new bootstrap.Offcanvas('#myOffcanvas')

{{< bs-table "table" >}}

Method Description
getInstance Static method which allows you to get the offcanvas instance associated with a DOM element
getOrCreateInstance Static method which allows you to get the offcanvas instance associated with a DOM element, or create a new one in case it wasn't initialized
hide Hides an offcanvas element. Returns to the caller before the offcanvas element has actually been hidden (i.e. before the hidden.bs.offcanvas event occurs).
show Shows an offcanvas element. Returns to the caller before the offcanvas element has actually been shown (i.e. before the shown.bs.offcanvas event occurs).
toggle Toggles an offcanvas element to shown or hidden. Returns to the caller before the offcanvas element has actually been shown or hidden (i.e. before the shown.bs.offcanvas or hidden.bs.offcanvas event occurs).
{{< /bs-table >}}

Events

Bootstrap's offcanvas class exposes a few events for hooking into offcanvas functionality.

{{< bs-table "table" >}}

Event type Description
hide.bs.offcanvas This event is fired immediately when the hide method has been called.
hidden.bs.offcanvas This event is fired when an offcanvas element has been hidden from the user (will wait for CSS transitions to complete).
hidePrevented.bs.offcanvas This event is fired when the offcanvas is shown, its backdrop is static and a click outside of the offcanvas is performed. The event is also fired when the escape key is pressed and the keyboard option is set to false.
show.bs.offcanvas This event fires immediately when the show instance method is called.
shown.bs.offcanvas This event is fired when an offcanvas element has been made visible to the user (will wait for CSS transitions to complete).
{{< /bs-table >}} 
const myOffcanvas = document.getElementById('myOffcanvas')
myOffcanvas.addEventListener('hidden.bs.offcanvas', event => {
  // do something...
})