Getting Started

Install

Install with npm:

npm install focus-overlay

Install in browser:

<!-- In the <head> -->
<link rel="stylesheet" href="//unpkg.com/focus-overlay@latest/dist/focusoverlay.css" />

<!-- End of <body> -->
<script src="//unpkg.com/focus-overlay@latest/dist/focusoverlay.js"></script>

The CSS is small enough to copy directly into your project's main stylesheet if you desire.

Library for creating overlays on focused elements. It was built with accessibility in mind with trigger keys and ARIA roles.

Usage

FocusOverlay(element, options)

import FocusOverlay from 'focusoverlay';

// Option 1: Zero config - Scopes to <body> element and uses default settings
const fo = new FocusOverlay();

// Option 2: Define an element
const fo = new FocusOverlay(document.body, options);

The element is what FocusOverlay will be scoped to. It takes either a string CSS selector or an HTML element. If no element is supplied it will scope to the <body> element by default.

The options is an optional parameter. Takes an object. See options for more info.

By default Focus Overlay will show and animate when hitting keyboard keys such as the Tab key. It's also preconfigured to animate via CSS transitions.

Options & Methods

Options

The default options are:

// Class added to the focus box
class: 'focus-overlay',
// Class added while the focus box is active
activeClass: 'focus-overlay-active',
// Class added while the focus box is animating
animatingClass: 'focus-overlay-animating',
// Class added to the target element
targetClass: 'focus-overlay-target',
// z-index of focus box
zIndex: 9001,
// Duration of the animatingClass (milliseconds)
duration: 500,
// Removes activeClass after duration
inactiveAfterDuration: false,
// Tab, Arrow Keys, Enter, Space, Shift, Ctrl, Alt, ESC
triggerKeys: [9, 36, 37, 38, 39, 40, 13, 32, 16, 17, 18, 27],
// Make focus box inactive when a non specified key is pressed
inactiveOnNonTriggerKey: true,
// Make focus box inactive when a user clicks
inactiveOnClick: true,
// Force the box to always stay active. Overrides everything
alwaysActive: false,
// Reposition focus box on transitionEnd for focused elements
watchTransitionEnd: true,
// Initialization event
onInit: function(focusoverlay) {},
// Before focus box move
onBeforeMove: function(focusoverlay) {},
// After focus box move
onAfterMove: function(focusoverlay) {},
// After FocusOverlay is destroyed
onDestroy: function(focusoverlay) {}

Methods

// Example use of the "moveFocusBox" method
focusoverlay.moveFocusBox(document.querySelector('body'));

moveFocusBox

Arguments: Element

Moves the focusBox to a target element

Destroy

Arguments: None

Deconstructs the FocusOverlay instance

Data Attributes

In some cases you might want FocusOverlay to ignore certain elements, or focus other elements instead. There are a few options available:

Example usage for data-focus:

<div id="input-wrapper">
  <input type="text" data-focus="#input-wrapper" />
</div>

In this example when the user focuses the input, FocusOverlay will instead target the wrapper. The data-focus attribute accepts a querySelector string.

Example usage for data-focus-label:

<label for="stylized-checkbox" class="rounded-checkbox">Click me</label>
<input
  id="stylized-checkbox"
  type="checkbox"
  class="visually-hidden"
  data-focus-label
/>

In this example when the user focuses the input, FocusOverlay will instead target its associated label.

Example usage for data-focus-ignore:

<a href="/info.html" data-focus-ignore>Really important information here!</a>

In this example FocusOverlay will not target this element at all.

Examples

Below contains various html controls and demonstrates when the keyboard is being used to show FocusOverlay.

Common controls

Editable text

Transitions

Iframe

Content Editables

Contenteditable explicitly set to true
Contenteditable
Contenteditable with textbox role

Focusable <div>s

tabindex="0"
tabindex="-1"
tabindex="0"

Selects

Other