What is focus-lock?
The focus-lock npm package is designed to trap focus within a specified DOM element, typically used in modal dialogs, popups, and similar components to enhance accessibility and user experience. It prevents users from tabbing out of the focused area into other parts of the webpage, ensuring that keyboard and screen reader users have a confined, manageable interaction space.
What are focus-lock's main functionalities?
Focus trapping within a DOM element
This feature allows developers to create a focus trap around a specified DOM element. When activated, all tab and shift+tab keystrokes are confined within the element, enhancing accessibility for modal dialogs.
import { FocusTrap } from 'focus-lock';
const focusTrap = new FocusTrap('#myDialog');
focusTrap.activate();
// When done
focusTrap.deactivate();
Auto focusing on the first focusable element
Automatically focuses the first focusable element within the component when activated. This is useful for ensuring that users start interacting with the most relevant part of a newly opened UI component.
import { AutoFocusInside } from 'focus-lock';
<AutoFocusInside>
<input type='text' />
<button>Click me</button>
</AutoFocusInside>
Return focus to initial element on deactivation
When the focus lock is deactivated, focus can be programmatically moved back to the initially focused element before the focus lock was activated, maintaining a logical flow of interaction.
import { MoveFocusInside } from 'focus-lock';
const initialFocus = document.getElementById('initialFocus');
// After deactivating the focus lock
MoveFocusInside(initialFocus);
Other packages similar to focus-lock
react-focus-lock
A React-specific implementation of focus trapping. It provides similar functionalities as focus-lock but is tailored for React applications, making it easier to integrate with React component lifecycle.
a11y-dialog
This package provides a lightweight yet robust solution for creating accessible dialog windows. While it includes focus trapping as part of its functionality, it also manages aria attributes and supports multiple dialog instances, offering a broader scope compared to focus-lock.
focus-lock
It is a trap! We got your focus and will not let him out!
#WHY?
From MDN Article about accessible dialogs:
- The dialog must be properly labeled
- Keyboard focus must be managed correctly
This one is about managing the focus.
I'v got a good article about focus management, dialogs and WAI-ARIA.
#Implementations
This is vanilla js base package for:
This is a small, but very useful for:
- Modal dialogs. You can not leave it with "Tab", ie tab-out.
- Focused tasks. It will aways brings you back.
#API
default(topNode, lastNode)
(aka setFocus), moves focus inside topNode, keeping in mind that last focus inside was - lastNode
Licence
MIT