Collapse

Collapse

The Bootstrap collapse plugin allows you to toggle content on your pages with a few classes thanks to some helpful JavaScript.

Contents

• Example
• Accordion example
• Accessibility
• Usage
  • Via data attributes
  • Via JavaScript
  • Options
  • Methods
    • .collapse(options)
    • .collapse('toggle')
    • .collapse('show')
    • .collapse('hide')
  • Events

Example

Click the buttons below to show and hide another element via class changes:

• .collapse hides content
• .collapsing is applied during transitions
• .collapse.show shows content

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

<p>
  <a class="btn btn-primary" data-toggle="collapse" href="#collapseExample" aria-expanded="false" aria-controls="collapseExample">
    Link with href
  </a>
  <button class="btn btn-primary" type="button" data-toggle="collapse" data-target="#collapseExample" aria-expanded="false" aria-controls="collapseExample">
    Button with data-target
  </button>
</p>
<div class="collapse" id="collapseExample">
  <div class="card card-block">
    Anim pariatur cliche reprehenderit, enim eiusmod high life accusamus terry richardson ad squid. Nihil anim keffiyeh helvetica, craft beer labore wes anderson cred nesciunt sapiente ea proident.
  </div>
</div>

Accordion example

Extend the default collapse behavior to create an accordion.

<div id="accordion" role="tablist" aria-multiselectable="true">
  <div class="card">
    <div class="card-header" role="tab" id="headingOne">
      <h5 class="mb-0">
        <a data-toggle="collapse" data-parent="#accordion" href="#collapseOne" aria-expanded="true" aria-controls="collapseOne">
          Collapsible Group Item #1
        </a>
      </h5>
    </div>

    <div id="collapseOne" class="collapse show" role="tabpanel" aria-labelledby="headingOne">
      <div class="card-block">
        Anim pariatur cliche reprehenderit, enim eiusmod high life accusamus terry richardson ad squid. 3 wolf moon officia aute, non cupidatat skateboard dolor brunch. Food truck quinoa nesciunt laborum eiusmod. Brunch 3 wolf moon tempor, sunt aliqua put a bird on it squid single-origin coffee nulla assumenda shoreditch et. Nihil anim keffiyeh helvetica, craft beer labore wes anderson cred nesciunt sapiente ea proident. Ad vegan excepteur butcher vice lomo. Leggings occaecat craft beer farm-to-table, raw denim aesthetic synth nesciunt you probably haven't heard of them accusamus labore sustainable VHS.
      </div>
    </div>
  </div>
  <div class="card">
    <div class="card-header" role="tab" id="headingTwo">
      <h5 class="mb-0">
        <a class="collapsed" data-toggle="collapse" data-parent="#accordion" href="#collapseTwo" aria-expanded="false" aria-controls="collapseTwo">
          Collapsible Group Item #2
        </a>
      </h5>
    </div>
    <div id="collapseTwo" class="collapse" role="tabpanel" aria-labelledby="headingTwo">
      <div class="card-block">
        Anim pariatur cliche reprehenderit, enim eiusmod high life accusamus terry richardson ad squid. 3 wolf moon officia aute, non cupidatat skateboard dolor brunch. Food truck quinoa nesciunt laborum eiusmod. Brunch 3 wolf moon tempor, sunt aliqua put a bird on it squid single-origin coffee nulla assumenda shoreditch et. Nihil anim keffiyeh helvetica, craft beer labore wes anderson cred nesciunt sapiente ea proident. Ad vegan excepteur butcher vice lomo. Leggings occaecat craft beer farm-to-table, raw denim aesthetic synth nesciunt you probably haven't heard of them accusamus labore sustainable VHS.
      </div>
    </div>
  </div>
  <div class="card">
    <div class="card-header" role="tab" id="headingThree">
      <h5 class="mb-0">
        <a class="collapsed" data-toggle="collapse" data-parent="#accordion" href="#collapseThree" aria-expanded="false" aria-controls="collapseThree">
          Collapsible Group Item #3
        </a>
      </h5>
    </div>
    <div id="collapseThree" class="collapse" role="tabpanel" aria-labelledby="headingThree">
      <div class="card-block">
        Anim pariatur cliche reprehenderit, enim eiusmod high life accusamus terry richardson ad squid. 3 wolf moon officia aute, non cupidatat skateboard dolor brunch. Food truck quinoa nesciunt laborum eiusmod. Brunch 3 wolf moon tempor, sunt aliqua put a bird on it squid single-origin coffee nulla assumenda shoreditch et. Nihil anim keffiyeh helvetica, craft beer labore wes anderson cred nesciunt sapiente ea proident. Ad vegan excepteur butcher vice lomo. Leggings occaecat craft beer farm-to-table, raw denim aesthetic synth nesciunt you probably haven't heard of them accusamus labore sustainable VHS.
      </div>
    </div>
  </div>
</div>

Accessibility

Be sure to add aria-expanded to the control element. This attribute explicitly defines the current state of the collapsible element to screen readers and similar assistive technologies. If the collapsible element is closed by default, it should have a value of aria-expanded="false". If you’ve set the collapsible element to be open by default using the show class, set aria-expanded="true" on the control instead. The plugin will automatically toggle this attribute based on whether or not the collapsible element has been opened or closed.

Additionally, if your control element is targeting a single collapsible element – i.e. the data-target attribute is pointing to an id selector – you may add an additional aria-controls attribute to the control element, containing the id of the collapsible element. Modern screen readers and similar assistive technologies make use of this attribute to provide users with additional shortcuts to navigate directly to the collapsible element itself.

Usage

The collapse plugin utilizes a few classes to handle the heavy lifting:

• .collapse hides the content
• .collapse.show shows the content
• .collapsing is added when the transition starts, and removed when it finishes

These classes can be found in _transitions.scss.

Via data attributes

Just add data-toggle="collapse" and a data-target to the element to automatically assign control of a collapsible element. The data-target attribute accepts a CSS selector to apply the collapse to. Be sure to add the class collapse to the collapsible element. If you’d like it to default open, add the additional class show.

To add accordion-like group management to a collapsible control, add the data attribute data-parent="#selector". Refer to the demo to see this in action.

Via JavaScript

Enable manually with:

$('.collapse').collapse()

Options

Options can be passed via data attributes or JavaScript. For data attributes, append the option name to data-, as in data-parent="".

Name Type Default Description

parent selector false If a selector is provided, then all collapsible elements under the specified parent will be closed when this collapsible item is shown. (similar to traditional accordion behavior - this is dependent on the panel class) toggle boolean true Toggles the collapsible element on invocation

Methods

.collapse(options)

Activates your content as a collapsible element. Accepts an optional options object.

$('#myCollapsible').collapse({
  toggle: false
})

.collapse('toggle')

Toggles a collapsible element to shown or hidden.

.collapse('show')

Shows a collapsible element.

.collapse('hide')

Hides a collapsible element.

Events

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

Event Type Description

show.bs.collapse This event fires immediately when the show instance method is called. shown.bs.collapse This event is fired when a collapse element has been made visible to the user (will wait for CSS transitions to complete). hide.bs.collapse This event is fired immediately when the hide method has been called. hidden.bs.collapse This event is fired when a collapse element has been hidden from the user (will wait for CSS transitions to complete).

$('#myCollapsible').on('hidden.bs.collapse', function () {
  // do something…
})