React Focus Trap Hook for Refs

Lightweight and accessible focus trap react hook. Great for modals and dialog boxes.

Install

yarn add @pofo/focus-trap
npm i @pofo/focus-trap

🚀 Features 🚀

• Only enables tab movements within the focused target
• Customize inital focus on the target
• Resets initial focus after focused target goes away

Basic Usage

import { useRef, useState } from 'react';
import useFocusTrap from '@pofo/focus-trap';

const MyComponent = () => {
    
    const ref = useRef( null );
    const [ isActive, setIsActive ] = useState( false );

    const styles = {
        visibility: isActive ? 'visible' : 'hidden';
    }

    useFocusTrap( ref, isActive );

    return (
        <>
            <button onClick={ setIsActive( state => !state ) }>Toggle the div below!</button>
            <div style={styles} ref={ref}>
                Hi!
                <button>Try clicking Tab!</button>
                <button>har har har</button>
            </div>
            <button>You can only tab me when the div above is not active!</button>
        </>
    )
}

!IMPORTANT!

• useFocusTrap only works if there is AT LEAST one focuable element within the target. That one focusable element should probably be a close button to close the target.
• Your toggle button to mount and unmount the modal / dialog box needs to be an immediate sibling of your modal / dialog box (right before). This is important for both functionality and coherent HTML structure.
• Your modal / dialog box component should have a focusable element as its last HTML element. As of now, if the user clicks onto a non focusable element within the your modal / dialog component and the next focusable element if off the target - THE FOCUS TRAP WILL BREAK.

Customizing Options

By default, nothing on the target is focused when activated. This can be customized through the third optional options parameter.

    useFocusTrap( ref, isActive, {
        initialFocus: 'first', // focus the first available focusable element on the target
    } );
}

API

useFocusTrap<T extends HTMLElement>(
    // requried
    ref: RefObject<T>,
    // required
    isActive: boolean,
    // optional
    options: {
        initialFocus?: 'first' | 'none' | number,
        tabbableElems: 'string',
    },
)

Parameter	Default	Type	Description
ref	REQUIRED	RefObject<T>	ref of the target
isActive	REQUIRED	boolean	isActive state representing whether the target is on the screen
options	{ initialFocus: 'none', tabbableElems: '' }	{ initialFocus: 'first' | 'none' | number, tabbableElems: string }	Optional options object. initialFocus: When set to 'none', no element if focused on target mount. When set to 'first', the first tabbable element is given focus on the target. When set to a number, the corresponding order on the HTML tree structure within the target is given focus. So if you put 0, the first tabbable element will be given focus. 1, the next -> and so on. tabbableElems: Specify additional tabbable elements you want to add to the query selector. For example, you can add ', object' to add the object element to the tabbable elements array. Always preface the string with , . By default, the following elements are tabbable:

'a[href], button:not([disabled]), input:not([disabled]), select:not([disabled]), textarea:not([disabled]), area[href], form, audio[controls], video[controls], [tabindex="0"]'

Extra

Plays well with useClickOutsideRef

LICENSE

MIT