Radio Group

Coordinate a roving native radio group. Custom element

Choosing between components

One component, two levels of behavior. <ui-radio-group> adds roving focus and a single change event over the group; the plain <fieldset class="ui-choice-group"> below it is the same markup with no custom element, and native radios already give it arrow-key selection and one-of-many semantics. The element is an addition, not a replacement, so it is never a choice between a CSS version and a JavaScript version.

Radio Group

Copy this markup

<ui-radio-group value="system" aria-labelledby="theme-label">
  <span id="theme-label">Theme</span>
  <label class="ui-choice">
  <input class="ui-radio" type="radio" name="theme" value="system" checked>
  <span data-ui-part="body">System</span>
</label>
  <label class="ui-choice">
  <input class="ui-radio" type="radio" name="theme" value="light">
  <span data-ui-part="body">Light</span>
</label>
  <label class="ui-choice">
  <input class="ui-radio" type="radio" name="theme" value="dark">
  <span data-ui-part="body">Dark</span>
</label>
</ui-radio-group>
<fieldset class="ui-choice-group">
  <legend class="ui-label">Deploy target</legend>

  <label class="ui-choice" for="deploy-target-preview">
    <input class="ui-radio" id="deploy-target-preview" name="deploy-target" type="radio" value="preview" checked>
    <span data-ui-part="body">
      <span data-ui-part="title">Preview</span>

    </span>
  </label>
  <label class="ui-choice" for="deploy-target-production">
    <input class="ui-radio" id="deploy-target-production" name="deploy-target" type="radio" value="production">
    <span data-ui-part="body">
      <span data-ui-part="title">Production</span>

    </span>
  </label>

</fieldset>

Install

Styles and registration

import '@timelessui/components/css/tokens.css'
import '@timelessui/components/css/core/choice-groups.css'
import '@timelessui/components/css/core/forms.css'
import '@timelessui/components/css/themes/atmosphere/tokens.css'
import '@timelessui/components/css/themes/atmosphere/forms.css'
import '@timelessui/components/css/themes/atmosphere/choice-groups.css'
import '@timelessui/components/register/ui-radio-group'

A register/ import is a side effect: it defines the element as the module evaluates, so it has to run in code the browser loads. To register explicitly instead — to control the timing, or to define into another window — call the function from the matching define/ entry point, which registers nothing on its own:

Explicit registration

import { defineRadioGroupElement } from '@timelessui/components/define/ui-radio-group'
defineRadioGroupElement()

Anatomy

Parts are authored in your own markup and identified by the selector below, so your CSS can target the same anatomy without loading Timeless styles. Required parts must be present for the component to work. Private data-ui-internal-* hooks are written by the runtime and must never be authored.

<ui-radio-group>

Part	Required	Selector	Purpose
choice	Yes	input[type='radio']	One native radio input, sharing a name with the rest. Native form submission and reset keep working.

ui-choice-group

Part	Required	Selector	Purpose
description	No	[data-ui-part~='description']	Group-level help text under the legend.
error	No	[data-ui-part~='error']	Group-level validation message.

ui-choice

Part	Required	Selector	Purpose
body	No	[data-ui-part~='body']	Wrapper for the title and description beside the control.
title	No	[data-ui-part~='title']	The choice label text.
description	No	[data-ui-part~='description']	Supporting copy under the choice label.

Attributes

Every value below is implemented by the stylesheets this component ships. Boolean attributes are presence-based: author the attribute with no value, or omit it.

<ui-radio-group>

Attribute	Values	Default	Description
orientation	vertical · horizontal	vertical	Layout and arrow-key axis.
value	any string	—	The radio checked on load and after a form reset. Match one input’s value. Assign the value property for live changes.

ui-choice-group

Attribute	Values	Default	Description
data-ui-orientation	vertical · horizontal	vertical	Layout direction of the choices.
data-ui-density	compact · normal · spacious	normal	Gap between choices.

ui-choice

Attribute	Values	Default	Description
data-ui-density	compact · normal · spacious	normal	Gap between the control and its label.

Element API

Attributes above are the authoring surface. These are the DOM properties and events the registered element adds once it upgrades.

<ui-radio-group>

Property	Type	Notes
orientation	'vertical' | 'horizontal'	Reflects the orientation attribute, documented above.
defaultValue	string	Reflects the value attribute, documented above.
value	string	Live value. Assigning it does not rewrite the authored default and does not dispatch transition events.

Event	Detail	Description
ui-before-change	CustomEvent<RadioGroupChangeDetail>	Cancelable proposal dispatched before the checked radio changes. Call preventDefault() to reject the transition and keep the current value.
ui-change	CustomEvent<RadioGroupChangeDetail>	Dispatched after the checked radio has changed. Bubbles and is composed.

State

Native attributes, ARIA, and platform pseudo-classes are authoritative. Style state through the selectors below rather than adding your own state classes.

State	Source	How to express it
invalid	aria	Set aria-invalid="true" on the <fieldset> and describe the error.
invalid	native	Native :invalid, or aria-invalid="true".
disabled	native	Native disabled.

Styling

Root identity: ui-radio-group, ui-choice-group, ui-choice, ui-radio. Required stylesheets: tokens.css, core/choice-groups.css, core/forms.css, themes/atmosphere/tokens.css, themes/atmosphere/forms.css, themes/atmosphere/choice-groups.css.

This component adds no custom properties of its own. Restyle it through the design tokens or your own CSS.

Design tokens this component reads (26)

These are global Atmosphere tokens. Change them once at the theme level rather than per component.

--ui-accent · --ui-bg-control · --ui-bg-control-muted · --ui-bg-surface · --ui-bg-surface-subtle · --ui-danger · --ui-danger-soft · --ui-disabled-opacity · --ui-duration-fast · --ui-ease-standard · --ui-fg · --ui-fg-muted · --ui-fg-subtle · --ui-focus · --ui-line · --ui-line-strong · --ui-radius-md · --ui-radius-pill · --ui-radius-sm · --ui-shadow-control · --ui-shadow-inset · --ui-space-1 · --ui-space-2 · --ui-space-3 · --ui-space-4 · --ui-space-5

Accessibility

Keep the native elements, roles, and relationships shown in the example. Timeless adds only the state and keyboard coordination the platform does not already provide, and it never supplies your accessible names — those depend on your content.

Follows the Radio Group pattern from the ARIA Authoring Practices Guide.

Key	Action
Arrow keys	Move focus to the previous or next radio, following the orientation and skipping disabled ones.
Home / End	Move focus to the first or last enabled radio.

Native radio semantics do the rest: one tab stop per group, checked state, form submission, and reset. Timeless adds roving focus and change events without replacing the inputs.

Verify in context

Automated checks cover axe WCAG 2.2 A and AA rules on every documented route. Keyboard, zoom, forced-colors, and screen-reader review still belong to your application.

Before JavaScript runs

The markup above is complete and usable on its own: native controls submit, labels associate, and authored ARIA is already correct. Registration adds state synchronisation, focus management, and keyboard coordination on top of it.

More examples

Open Radio Group in StoryLite for variants, controls, and manual testing.