react-roving-focus v0.0.7

react-roving-focus

Flexible roving focus (aka roving tabindex) for React with support for any fixed or responsive layout.

Examples

Refer to the Storybook for various layout examples:

• Horizontal layout
• Vertical layout
• Grid layout
• Responsive grid layout
• Nested grid layout
• Masonry layout (aka modular grid)

How it works

Unlike traditional roving tabindex implementations, react-roving-focus determines navigation order using the rendered size and position of elements, rather than row or column indices. This enables keyboard navigation across any 1D or 2D layout (fixed or responsive) without any configuration.

Keyboard Support

Use the following keys to move focus between elements:

Performance

To minimize re-renders, each element maintains its own tabIndex state via the useRovingFocus() hook. The <RovingFocusGroup> updates individual tabIndex state values in response to element registration, unregistration, focus changes, and enabled/disabled state changes.

The <RovingFocusGroup> determines the 'first' and 'last' elements during registration and unregistration. To track accessibility state changes, a MutationObserver monitors the disabled and aria-disabled attributes of all registered elements.

When an arrow key is pressed, the 'next' element is calculated using multi-level filtering and simple distance calculations for efficiency. Element positions are intentionally not cached since layout changes (particularly those driven by state) may not be automatically detectable.

Performance has been stress tested using various layouts with 10,000 focusable elements.

Installation

npm install react-roving-focus
# or
pnpm add react-roving-focus
# or
bun add react-roving-focus

Usage

Wrap a group of focusable elements in a <RovingFocusGroup> and use the useRovingFocus() hook to control the tabIndex of each element.

import { RovingFocusGroup, useRovingFocus } from 'react-roving-focus';

function ExampleGroup() {
  return (
    <RovingFocusGroup>
      <div>
        <ExampleItem>1</ExampleItem>
        <ExampleItem>2</ExampleItem>
        <ExampleItem>3</ExampleItem>
      </div>
    </RovingFocusGroup>
  );
}

function ExampleItem({ children }: { children: React.ReactNode }) {
  const { ref, tabIndex } = useRovingFocus<HTMLButtonElement>();

  return (
    <button ref={ref} tabIndex={tabIndex}>
      {children}
    </button>
  );
}

With an existing ref

If a focusable element has an existing ref, provide it to the useRovingFocus() hook.

import { useRef } from 'react';
import { useRovingFocus } from 'react-roving-focus';

function ExampleItem({ children }: { children: React.ReactNode }) {
  const buttonRef = useRef<HTMLButtonElement>(null);
  const { tabIndex } = useRovingFocus({ ref: buttonRef });

  return (
    <button ref={buttonRef} tabIndex={tabIndex}>
      {children}
    </button>
  );
}

With disabled elements

To disable a focusable element, set the disabled or aria-disabled attribute on the focusable element.

import { useRovingFocus } from 'react-roving-focus';

function ExampleItem({ children }: { children: React.ReactNode }) {
  const { ref, tabIndex } = useRovingFocus<HTMLButtonElement>();

  return (
    <button ref={ref} tabIndex={tabIndex} disabled>
      {children}
    </button>
  );
}

Alternatively, set disabled: true in the useRovingFocus() hook.

import { useRovingFocus } from 'react-roving-focus';

function ExampleItem({ children }: { children: React.ReactNode }) {
  const { ref, tabIndex } = useRovingFocus<HTMLButtonElement>({
    disabled: true,
  });

  return (
    <button ref={ref} tabIndex={tabIndex}>
      {children}
    </button>
  );
}