accessible-dropdown

Accessible Dropdown

Build an accessible dropdown arround your markup.

• See accessible specificies
• Demo

Getting started

Install the package

We can install the package from NPM or Yarn.

yarn add @beapi/be-a11y

Then import the component in your JavaScript.

import { Dropdown } from '@beapi/be-a11y';

Add Dropdown HTML Layout

Copy the following markup on your HTML file :

<div class="dropdown">
    <span class="dropdown__label">Choose an element</span>
    <button aria-haspopup="listbox">Book</button>
    <ul tabindex="-1" role="listbox">
        <li role="option">Book</li>
        <li role="option">Movies</li>
        <li role="option">Music</li>
        <li role="option">Video games</li>
        <li role="option">Paint</li>
    </ul>
</div>

Initialize the component

Finally, we need to initialize this component in JavaScript.

import { Dropdown } from '@beapi/be-a11y';

Dropdown.init('.dropdown', {
  // Options here
});

If you have multiple dropdown with different HTML markup, you can set a preset and initialize all at once.

import { Dropdown } from '@beapi/be-a11y';

Dropdown.preset = {
  '#dropdown-1': {
    automaticSelection: true,
  },
  '#dropdown-2': {
    mediaQuery: window.matchMedia('(min-width: 1024px)'),
  },
};

Dropdown.initFromPreset();

Warning There is no embedded style. It's up to you to style the component as you see fit.

Options

name	type	default	description
automaticSelection	boolean || string	false	if true, first item is automatically selected, if string, check if element exists and it will be selected.
buttonSelector	string	button	Button selector.
labelSelector	string	.dropdown__label	Label selector.
listSelector	string	ul	Listbox selector.
mediaQuery	null or matchMedia object	null	Set dropdown for a specific media query.
nonSelectedItemLabel	string	No item selected	Default button text if no items are selected.
onChange	null or function	null	Event on dropdown change.
onClose	null or function	null	Event on dropdown close.
onListItemClick	null or function	null	Event on dropdown list item click.
onOpen	null or function	null	Event on dropdown open.
prefixId	string	dropdown	Define the prefix id of the component.

Methods

You can interract with the Dropdown component by adding or removing items. See example below.

<button id="add-item" type="button">Add new item</button>

<div class="dropdown">
    <span class="dropdown__label">Choose an element</span>
    <button aria-haspopup="listbox">Book</button>
    <ul tabindex="-1" role="listbox">
        <li role="option">Book</li>
        <li role="option">Movies</li>
        <li role="option">Music</li>
        <li role="option">Video games</li>
        <li role="option">Paint</li>
    </ul>
</div>

import { Dropdown } from '@beapi/be-a11y';

Dropdown.init('.dropdown');

const addButton = document.getElementById('add-item');
const dropdownInstance = Dropdown.getInstance('.dropdown');

addButton.addEventListener('click', function() {
  const newListItem = document.createElement('li');
  newListItem.innerText = 'Dummy';

  dropdownInstance.addItem(newListItem);
});

Name	Params	Description
addItem	listItem: HTMLElement	Adds a new list item to the dropdown.
removeItem	listItem: HTMLElement	Removes a specified list item from the dropdown.
removeAllItems	None	Removes all list items from the dropdown.