Collapse
Toggle the visibility of content across your project with a few classes and our JavaScript plugins.
How it works
The collapse JavaScript plugin is used to show and hide content. Buttons or anchors are used as triggers that are mapped to specific elements you toggle. Collapsing an element will animate the height from its current value to 0. Given how CSS handles animations, you cannot use padding on a .collapse element. Instead, use the class as an independent wrapping element.
Example
Click the buttons below to show and hide another element via class changes:
Generally, we recommend using a < button> with the data-bs-target attribute. While not recommended from a semantic point of view, you can also use an link with the href attribute (and a role="button"). In both cases, the data-bs-toggle="collapse" is required.
Horizontal
The collapse plugin supports horizontal collapsing. Add the .collapse-horizontal modifier class to transition the width instead of height and set a width on the immediate child element. Feel free to write your own custom Sass, use inline styles, or use our width utilities.
Multiple toggles and targets
A
Accessibility
Be sure to add aria-expanded to the control element. This attribute explicitly conveys the current state of the collapsible element tied to the control to screen readers and similar assistive technologies. If the collapsible element is closed by default, the attribute on the control element 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 on the control based on whether or not the collapsible element has been opened or closed (via JavaScript, or because the user triggered another control element also tied to the same collapsible element). If the control element’s HTML element is not a button (e.g., an < a> or < div>), the attribute role="button" should be added to the element.
If your control element is targeting a single collapsible element – i.e. the data-bs-target attribute is pointing to an id selector – you should add the 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.
Note that Bootstrap’s current implementation does not cover the various optional keyboard interactions described in the ARIA Authoring Practices Guide accordion pattern - you will need to include these yourself with custom JavaScript.
CSS
Sass variables
Classes
Collapse transition classes can be found in scss/_transitions.scss as these are shared across multiple components (collapse and accordion).
Usage
The collapse plugin utilizes a few classes to handle the heavy lifting:
These classes can be found in _transitions.scss.
Via data attributes
Just add data-bs-toggle="collapse" and a data-bs-target to the element to automatically assign control of one or more collapsible elements. The data-bs-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 area, add the data attribute data-bs-parent="#selector". Refer to the accordion page for more information.
Via JavaScript
Enable manually with:
Options
As options can be passed via data attributes or JavaScript, you can append an option name to data-bs-, as in data-bs-animation="{value}". Make sure to change the case type of the option name from “camelCase” to “kebab-case” when passing the options via data attributes. For example, use data-bs-custom-class="beautifier" instead of data-bs-customClass="beautifier".
As of Bootstrap 5.2.0, all components support an experimental reserved data attribute data-bs-config that can house simple component configuration as a JSON string. When an element has data-bs-config='{"delay":0, "title":123}' and data-bs-title="456" attributes, the final title value will be 456 and the separate data attributes will override values given on data-bs-config. In addition, existing data attributes are able to house JSON values like data-bs-delay='{"show":0,"hide":150}'.
The final configuration object is the merged result of data-bs-config, data-bs-, and js object where the latest given key-value overrides the others.
Methods
Activates your content as a collapsible element. Accepts an optional options object.
You can create a collapse instance with the constructor, for example:
Events
Bootstrap’s collapse class exposes a few events for hooking into collapse functionality.
