Co-authored-by: louismaximepiton <louismaxime.piton@orange.com>
13 KiB
layout | title | description | group | toc |
---|---|---|---|---|
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, 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
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
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 >}} Toggle right offcanvas
Offcanvas right
{{< example >}} Toggle bottom offcanvas
Offcanvas bottom
Backdrop
Scrolling the <body>
element is disabled when an offcanvas and its backdrop are visible. Use the data-bs-scroll
attribute to toggle <body>
scrolling and data-bs-backdrop
to toggle the backdrop.
{{< example >}} Enable body scrolling Enable backdrop (default) Enable both scrolling & backdrop
Colored with scrolling
Try scrolling the rest of the page to see this option in action.
Offcanvas with backdrop
.....
Backdrop with scrolling
Try scrolling the rest of the page to see this option in action.
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.
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-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:
var offcanvasElementList = Array.prototype.slice.call(document.querySelectorAll('.offcanvas'))
var offcanvasList = offcanvasElementList.map(function (offcanvasEl) {
return new bootstrap.Offcanvas(offcanvasEl)
})
Options
Options can be passed via data attributes or JavaScript. For data attributes, append the option name to data-bs-
, as in data-bs-backdrop=""
.
{{< bs-table "table" >}}
Name | Type | Default | Description |
---|---|---|---|
backdrop |
boolean | true |
Apply a backdrop on body while offcanvas is open |
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:
var myOffcanvas = document.getElementById('myOffcanvas')
var bsOffcanvas = new bootstrap.Offcanvas(myOffcanvas)
{{< bs-table "table" >}}
Method | Description |
---|---|
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). |
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). |
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). |
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 |
{{< /bs-table >}} |
Events
Bootstrap's offcanvas class exposes a few events for hooking into offcanvas functionality.
{{< bs-table "table" >}}
Event type | Description |
---|---|
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). |
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). |
{{< /bs-table >}} |
var myOffcanvas = document.getElementById('myOffcanvas')
myOffcanvas.addEventListener('hidden.bs.offcanvas', function () {
// do something...
})