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Collapsible: Overview

A combination of a button (the invoker) and a chunk of 'extra content'. This web component can be extended with an animation to disclose the extra content. There are two slots available respectively; invoker to specify the collapsible's invoker and content for the extra content of the collapsible.

export const main = () => html`
    <button slot="invoker">More about cars</button>
    <div slot="content">
      Most definitions of cars say that they run primarily on roads, seat one to eight people, have
      four tires, and mainly transport people rather than goods.


  • Use opened attribute or toggle() method to render default open.
  • invoker slot can be custom template e.g. our button or native button with custom styling.
  • Observe the state with the help of @opened-changed event.
  • show() and hide() are helper methods to hide or show the content from outside.


npm i --save @lion/ui
import { LionCollapsible } from '@lion/ui/collapsible.js';
// or
import '@lion/ui/define/lion-collapsible.js';