Offcanvas

    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 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.

    The animation effect of this component is dependent on the prefers-reduced-motion media query. See the .

    Examples

    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.

    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.

    Offcanvas - 图2

    1. <a class="btn btn-primary" data-bs-toggle="offcanvas" href="#offcanvasExample" role="button" aria-controls="offcanvasExample">
    2.   Link with href
    3. </a>
    4. <button class="btn btn-primary" type="button" data-bs-toggle="offcanvas" data-bs-target="#offcanvasExample" aria-controls="offcanvasExample">
    5.   Button with data-bs-target
    6. </button>
    8. <div class="offcanvas offcanvas-start" tabindex="-1" id="offcanvasExample" aria-labelledby="offcanvasExampleLabel">
    9.   <div class="offcanvas-header">
    10.     <h5 class="offcanvas-title" id="offcanvasExampleLabel">Offcanvas</h5>
    11.     <button type="button" class="btn-close text-reset" data-bs-dismiss="offcanvas" aria-label="Close"></button>
    12.   </div>
    13.   <div class="offcanvas-body">
    14.     <div>
    15.       Some text as placeholder. In real life you can have the elements you have chosen. Like, text, images, lists, etc.
    16.     </div>
    17.     <div class="dropdown mt-3">
    18.       <button class="btn btn-secondary dropdown-toggle" type="button" id="dropdownMenuButton" data-bs-toggle="dropdown">
    19.         Dropdown button
    20.       </button>
    21.       <ul class="dropdown-menu" aria-labelledby="dropdownMenuButton">
    22.         <li><a class="dropdown-item" href="#">Another action</a></li>
    23.         <li><a class="dropdown-item" href="#">Something else here</a></li>
    24.       </ul>
    25.     </div>
    26.   </div>
    27. </div>

    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

    1. <button class="btn btn-primary" type="button" data-bs-toggle="offcanvas" data-bs-target="#offcanvasTop" aria-controls="offcanvasTop">Toggle top offcanvas</button>
    3. <div class="offcanvas offcanvas-top" tabindex="-1" id="offcanvasTop" aria-labelledby="offcanvasTopLabel">
    4.   <div class="offcanvas-header">
    5.     <h5 id="offcanvasTopLabel">Offcanvas top</h5>
    6.     <button type="button" class="btn-close text-reset" data-bs-dismiss="offcanvas" aria-label="Close"></button>
    7.   </div>
    8.   <div class="offcanvas-body">
    9.     ...
    11. </div>

    Offcanvas - 图4

    1. <button class="btn btn-primary" type="button" data-bs-toggle="offcanvas" data-bs-target="#offcanvasRight" aria-controls="offcanvasRight">Toggle right offcanvas</button>
    3. <div class="offcanvas offcanvas-end" tabindex="-1" id="offcanvasRight" aria-labelledby="offcanvasRightLabel">
    4.   <div class="offcanvas-header">
    5.     <h5 id="offcanvasRightLabel">Offcanvas right</h5>
    6.     <button type="button" class="btn-close text-reset" data-bs-dismiss="offcanvas" aria-label="Close"></button>
    7.   </div>
    8.   <div class="offcanvas-body">
    9.     ...
    10.   </div>
    11. </div>

    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.

    Offcanvas - 图6

    1. <button class="btn btn-primary" type="button" data-bs-toggle="offcanvas" data-bs-target="#offcanvasScrolling" aria-controls="offcanvasScrolling">Enable body scrolling</button>
    2. <button class="btn btn-primary" type="button" data-bs-toggle="offcanvas" data-bs-target="#offcanvasWithBackdrop" aria-controls="offcanvasWithBackdrop">Enable backdrop (default)</button>
    3. <button class="btn btn-primary" type="button" data-bs-toggle="offcanvas" data-bs-target="#offcanvasWithBothOptions" aria-controls="offcanvasWithBothOptions">Enable both scrolling & backdrop</button>
    5. <div class="offcanvas offcanvas-start" data-bs-scroll="true" data-bs-backdrop="false" tabindex="-1" id="offcanvasScrolling" aria-labelledby="offcanvasScrollingLabel">
    6.   <div class="offcanvas-header">
    7.     <h5 class="offcanvas-title" id="offcanvasScrollingLabel">Colored with scrolling</h5>
    8.     <button type="button" class="btn-close text-reset" data-bs-dismiss="offcanvas" aria-label="Close"></button>
    9.   </div>
    10.   <div class="offcanvas-body">
    11.     <p>Try scrolling the rest of the page to see this option in action.</p>
    12.   </div>
    13. </div>
    14.   <div class="offcanvas-header">
    15.     <h5 class="offcanvas-title" id="offcanvasWithBackdropLabel">Offcanvas with backdrop</h5>
    16.     <button type="button" class="btn-close text-reset" data-bs-dismiss="offcanvas" aria-label="Close"></button>
    17.   </div>
    18.   <div class="offcanvas-body">
    19.     <p>.....</p>
    20.   </div>
    21. </div>
    22. <div class="offcanvas offcanvas-start" data-bs-scroll="true" tabindex="-1" id="offcanvasWithBothOptions" aria-labelledby="offcanvasWithBothOptionsLabel">
    23.   <div class="offcanvas-header">
    24.     <h5 class="offcanvas-title" id="offcanvasWithBothOptionsLabel">Backdroped with scrolling</h5>
    25.     <button type="button" class="btn-close text-reset" data-bs-dismiss="offcanvas" aria-label="Close"></button>
    26.   </div>
    27.   <div class="offcanvas-body">
    28.     <p>Try scrolling the rest of the page to see this option in action.</p>
    29.   </div>
    30. </div>

    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

    1. $offcanvas-padding-y:               $modal-inner-padding;
    2. $offcanvas-padding-x:               $modal-inner-padding;
    3. $offcanvas-horizontal-width:        400px;
    4. $offcanvas-vertical-height:         30vh;
    5. $offcanvas-transition-duration:     .3s;
    7. $offcanvas-border-width:            $modal-content-border-width;
    8. $offcanvas-title-line-height:       $modal-title-line-height;
    9. $offcanvas-bg-color:                $modal-content-bg;
    10. $offcanvas-color:                   $modal-content-color;
    11. $offcanvas-box-shadow:              $modal-content-box-shadow-xs;
    12. $offcanvas-backdrop-bg:             $modal-backdrop-bg;
    13. $offcanvas-backdrop-opacity:        $modal-backdrop-opacity;

    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

    1. <button type="button" class="btn-close" data-bs-dismiss="offcanvas" aria-label="Close"></button>

    or on a button outside the offcanvas using the data-bs-target as demonstrated below:

    While both ways to dismiss an offcanvas are supported, keep in mind that dismissing from outside an offcanvas does not match . Do this at your own risk.

    Enable manually with:

    1. var offcanvasElementList = [].slice.call(document.querySelectorAll('.offcanvas'))
    2. var offcanvasList = offcanvasElementList.map(function (offcanvasEl) {
    3.   return new bootstrap.Offcanvas(offcanvasEl)
    4. })

    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="".

    Asynchronous methods and transitions

    All API methods are asynchronous and start a transition. They return to the caller as soon as the transition is started but before it ends. In addition, a method call on a transitioning component will be ignored.

    See our JavaScript documentation for more information.

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

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

    1. var myOffcanvas = document.getElementById('myOffcanvas')
    2. var bsOffcanvas = new bootstrap.Offcanvas(myOffcanvas)

    Events

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

    1. var myOffcanvas = document.getElementById('myOffcanvas')
    2. myOffcanvas.addEventListener('hidden.bs.offcanvas', function () {