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Disclosure is a component whose visibility is changed using trigger buttons.

Disclosure conforms to the W3C WAI-ARIA authoring practices.

Set up

First import the styles into your main SASS file, replacing <path-to-node_modules> with the path to the node_modules directory relative to the file:

@import '<path-to-node_modules>/@potato/ace/components/disclosure/disclosure';

Alternatively ace.scss includes all ACE component SASS files, so if using multiple ACE components it can be imported instead:

@import '<path-to-node_modules>/@potato/ace/ace';

A CSS file is also provided for convenience and is located at <path-to-node_modules>/@potato/ace/components/disclosure/ace-disclosure.css.

Then import the class into your JavaScript entry point:

import '<path-to-node_modules>/@potato/ace/components/disclosure/disclosure';

For convenience the ES6 class is exported as Disclosure and the attribute names used by the class are exported as properties of ATTRS.

After the event DOMContentLoaded is fired on document an instance of Disclosure is instantiated within each <ace-disclosure> element and an ID ace-disclosure-<n> is added for any instance without one, where <n> is a unique integer. Once instantiation is complete a custom event ace-disclosure-ready is dispatched to window. See the Custom events section below for more details.


Disclosures are hidden by default but can be initially shown on page load by adding the ace-disclosure-visible="true" attribute to it. The attribute ace-disclosure-trigger-for should be added to triggering element and its value set to the ID of the Disclosure to be triggered. For accessibility reasons it is recommended that only <button> elements are used for triggers. Disclosures can also be triggered using a custom event. See the Custom events section below for more details.

Triggers will by default toggle the visibiility of the Disclosure, but the ace-disclosure-show-trigger or ace-disclosure-hide-trigger attribute can be added to the trigger to ensure that it only shows or hides its Disclosure respectively.


The following SASS is applied to Disclosure.

ace-disclosure:not([ace-disclosure-visible]) {
	display: none;

Custom events

Disclosure uses the following custom events, the names of which are available in its exported EVENTS object, similar to ATTRS, so they may be imported into other modules.

Dispatched events

The following events are dispatched to window by Disclosure.



This event is dispatched when Disclosure finishes initialising. The event name is available as EVENTS.OUT.READY and its detail property is composed as follows:

'detail': {
	'id': // ID of Disclosure [string]

Visibility changed


This event is dispatched when Disclosure's visibility changes. The event name is available as EVENTS.OUT.VISIBILITY_CHANGED and its detail property is composed as follows:

'detail': {
	'id': // ID of Disclosure [string]
	'visible': // Whether the Disclosure is visible or not [boolean]

Listened for event

Disclosure listens for the following event that should be dispatched to window.



This event should be dispatched to toggle the visibility of the Disclosure. The event name is available as EVENTS.IN.TOGGLE and its detail property should be composed as follows:

'detail': {
	'id': // ID of target Disclosure [string]


Each example contains a live demo and the HTML code that produced it. The code shown may differ slightly to that rendered for the demo as some components may alter their HTML when they initialise.

Simple Disclosure

This is a simple, button-triggered Disclosure.

Disclosure heading

Disclosure content.

Potato logo
<button ace-disclosure-trigger-for="ace-disclosure-1">
	Disclosure toggle
<ace-disclosure id="ace-disclosure-1">
	<h2>Disclosure heading</h2>
	<p>Disclosure content.</p>
	<img src="/img/logo.svg" height="100px" alt="Potato logo" />

Initially visible Disclosure

In this example Disclosure 1 is initially hidden, whereas Disclosure 2 is initially visible as it has the attribute ace-disclosure-visible="true".

Initially visible disclosure

This Disclosure is initially visible because it has the attribute ace-disclosure-visible="true".

Potato Spuddy with headphones and phone
<button ace-disclosure-trigger-for="ace-initially-visible-disclosure">
	Disclosure toggle trigger 1
<button ace-disclosure-trigger-for="ace-initially-visible-disclosure">
	Disclosure toggle trigger 2
<button ace-disclosure-trigger-for="ace-initially-visible-disclosure" ace-disclosure-trigger-show>
	Disclosure show trigger
<button ace-disclosure-trigger-for="ace-initially-visible-disclosure" ace-disclosure-trigger-hide>
	Disclosure hide trigger
<ace-disclosure ace-disclosure-visible id="ace-initially-visible-disclosure">
	<h2>Initially visible disclosure</h2>
	<p>This Disclosure is initially visible because it has the attribute <code>ace-disclosure-visible="true"</code>.</p>
	<img src="/img/phone-spuddy.png" height="100px" alt="Potato Spuddy with headphones and phone" />

Disclosure controlled using custom event

The button in this example is not a trigger button but instead is a button that dispatches the ace-disclosure-toggle custom event on the Dsiclosure. This implementation is only for demonstration purposes and trigger buttons should have the ace-disclosure-trigger-for attribute instead. The JavaScript used by this example is shown below.

Custom event Disclosure

This Disclosure's visibility is controlled using custom events.

Potato logo
<button id="toggle-custom-event-btn">
	Toggle disclosure using custom event
<ace-disclosure id="ace-custom-events-disclosure">
	<h2>Custom event Disclosure</h2>
	<p>This Disclosure's visibility is controlled using custom events.</p>
	<img src="/img/logo.svg" height="100px" alt="Potato logo" />
import { EVENTS } from '/ace/components/disclosure/disclosure.js';

document.addEventListener('DOMContentLoaded', () => {
	const customEventBtn = document.getElementById('toggle-custom-event-btn');

	customEventBtn.addEventListener('click', () => {
		window.dispatchEvent(new CustomEvent(
			{'detail': {'id': 'ace-custom-events-disclosure'}},