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This file is licensed to you under the Apache License, Version 2.0 (the "License");
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import {Layout} from '@react-spectrum/docs';
export default Layout;

import docs from 'docs:react-aria-components';
import statelyDocs from 'docs:@react-stately/checkbox';
import typesDocs from 'docs:@react-types/shared/src/events.d.ts';
import {PropTable, HeaderInfo, TypeLink, PageDescription, StateTable, ContextTable, VersionBadge, ClassAPI} from '@react-spectrum/docs';
import styles from '@react-spectrum/docs/src/docs.css';
import packageData from 'react-aria-components/package.json';
import Anatomy from '/packages/react-aria/docs/checkbox/checkboxgroup-anatomy.svg';
import ChevronRight from '@spectrum-icons/workflow/ChevronRight';
import {Divider} from '@react-spectrum/divider';
import {ExampleCard} from '@react-spectrum/docs/src/ExampleCard';
import {Keyboard} from '@react-spectrum/text';
import Label from '@react-spectrum/docs/pages/assets/component-illustrations/Label.svg';
import Form from '@react-spectrum/docs/pages/assets/component-illustrations/Form.svg';
import {StarterKits} from '@react-spectrum/docs/src/StarterKits';

---
category: Forms
keywords: [checkbox, input, aria]
type: component
---

# CheckboxGroup

<PageDescription>{docs.exports.CheckboxGroup.description}</PageDescription>

<HeaderInfo
  packageData={packageData}
  componentNames={['CheckboxGroup']}
  sourceData={[
    {type: 'W3C', url: 'https://www.w3.org/WAI/ARIA/apg/patterns/checkbox/'}
  ]} />

## Example

```tsx example
import {CheckboxGroup, Checkbox, Label} from 'react-aria-components';

<CheckboxGroup>
  <Label>Favorite sports</Label>
  <Checkbox value="soccer">
    <div className="checkbox" aria-hidden="true">
      <svg viewBox="0 0 18 18"><polyline points="1 9 7 14 15 4" /></svg>
    </div>
    Soccer
  </Checkbox>
  <Checkbox value="baseball">
    <div className="checkbox" aria-hidden="true">
      <svg viewBox="0 0 18 18"><polyline points="1 9 7 14 15 4" /></svg>
    </div>
    Baseball
  </Checkbox>
  <Checkbox value="basketball">
    <div className="checkbox" aria-hidden="true">
      <svg viewBox="0 0 18 18"><polyline points="1 9 7 14 15 4" /></svg>
    </div>
    Basketball
  </Checkbox>
</CheckboxGroup>
```

<details>
  <summary style={{fontWeight: 'bold'}}><ChevronRight size="S" /> Show CSS</summary>
```css hidden
@import './Checkbox.mdx' layer(checkbox);
@import './Form.mdx' layer(form);
@import './Button.mdx' layer(button);
```

```css
@import "@react-aria/example-theme";

.react-aria-CheckboxGroup {
  display: flex;
  flex-direction: column;
  gap: 0.571rem;
  color: var(--text-color);
}
```

</details>

## Features

Checkbox groups can be built in HTML with the
[&lt;fieldset&gt;](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/fieldset)
and [&lt;input&gt;](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/input) elements,
however these can be difficult to style. `CheckboxGroup` helps achieve accessible
checkbox groups that can be styled as needed.

* **Accessible** – Checkbox groups are exposed to assistive technology via ARIA, and automatically associate a nested `<Label>`. Description and error message help text slots are supported as well.
* **HTML form integration** – Each individual checkbox uses a visually hidden `<input>` element under the hood, which enables HTML form integration and autofill.
* **Validation** – Support for native HTML constraint validation with customizable UI, custom validation functions, and server-side validation errors.

## Anatomy

<Anatomy />

A checkbox group consists of a set of checkboxes, and a label. Each checkbox
includes a label and a visual selection indicator. Zero or more checkboxes
within the group can be selected at a time. Users may click or touch a checkbox
to select it, or use the <Keyboard>Tab</Keyboard> key to navigate to it
and the <Keyboard>Space</Keyboard> key to toggle it.

`CheckboxGroup` also supports optional description and error message elements, which can be used
to provide more context about the field, and any validation messages. These are linked with the
inputs via the `aria-describedby` attribute.

```tsx
import {CheckboxGroup, Checkbox, Label, Text, FieldError} from 'react-aria-components';

<CheckboxGroup>
  <Label />
  <Checkbox />
  <Text slot="description" />
  <FieldError />
</CheckboxGroup>
```

Individual checkboxes must have a visual label. If the checkbox group does not have a visible label,
an `aria-label` or `aria-labelledby` prop must be passed instead to identify the element to assistive
technology.

### Concepts

`CheckboxGroup` makes use of the following concepts:

<section className={styles.cardGroup} data-size="small">

<ExampleCard
  url="forms.html"
  title="Forms"
  description="Validating and submitting form data, and integrating with form libraries.">
  <Form />
</ExampleCard>

</section>

### Composed components

A `CheckboxGroup` uses the following components, which may also be used standalone or reused in other components.

<section className={styles.cardGroup} data-size="small">

<ExampleCard
  url="https://developer.mozilla.org/en-US/docs/Web/HTML/Element/label"
  title="Label"
  description="A label provides context for an element.">
  <Label />
</ExampleCard>

</section>

## Starter kits

To help kick-start your project, we offer starter kits that include example implementations of all React Aria components with various styling solutions. All components are fully styled, including support for dark mode, high contrast mode, and all UI states. Each starter comes with a pre-configured [Storybook](https://storybook.js.org/) that you can experiment with, or use as a starting point for your own component library.

<StarterKits component="checkboxgroup" />

## Reusable wrappers

If you will use a CheckboxGroup in multiple places in your app, you can wrap all of the pieces into a reusable component. This way, the DOM structure, styling code, and other logic are defined in a single place and reused everywhere to ensure consistency.

This example wraps `CheckboxGroup` and all of its children together into a single component which accepts a `label` prop, which is passed to the right place. It also shows how to use the `description` slot to render [help text](#description), and `FieldError` component to render [validation errors](#validation).

```tsx example export=true
import type {CheckboxGroupProps, CheckboxProps, ValidationResult} from 'react-aria-components';
import {Text, FieldError} from 'react-aria-components';

interface MyCheckboxGroupProps extends Omit<CheckboxGroupProps, 'children'> {
  children?: React.ReactNode,
  label?: string,
  description?: string,
  errorMessage?: string | ((validation: ValidationResult) => string)
}

export function MyCheckboxGroup({
  label,
  description,
  errorMessage,
  children,
  ...props
}: MyCheckboxGroupProps) {
  return (
    <CheckboxGroup {...props}>
      {label && <Label>{label}</Label>}
      {children}
      {description && <Text slot="description">{description}</Text>}
      <FieldError>{errorMessage}</FieldError>
    </CheckboxGroup>
  );
}

interface MyCheckboxProps extends Omit<CheckboxProps, 'children'> {
  children?: React.ReactNode
}

function MyCheckbox({children, ...props}: MyCheckboxProps) {
  return (
    <Checkbox {...props}>
      <div className="checkbox" aria-hidden="true">
        <svg viewBox="0 0 18 18"><polyline points="1 9 7 14 15 4" /></svg>
      </div>
      {children}
    </Checkbox>
  );
}

<MyCheckboxGroup label="Favorite sports">
  <MyCheckbox value="soccer">Soccer</MyCheckbox>
  <MyCheckbox value="baseball">Baseball</MyCheckbox>
  <MyCheckbox value="basketball">Basketball</MyCheckbox>
</MyCheckboxGroup>
```

## Value

### Default value

An initial, uncontrolled value can be provided to the CheckboxGroup using the `defaultValue` prop, which accepts an array of selected items that map to the
`value` prop on each Checkbox.

```tsx example
<MyCheckboxGroup label="Favorite sports (uncontrolled)" defaultValue={['soccer', 'baseball']}>
  <MyCheckbox value="soccer">Soccer</MyCheckbox>
  <MyCheckbox value="baseball">Baseball</MyCheckbox>
  <MyCheckbox value="basketball">Basketball</MyCheckbox>
</MyCheckboxGroup>
```

### Controlled value

A controlled value can be provided using the `value` prop, which accepts an array of selected items, which map to the
`value` prop on each Checkbox. The `onChange` event is fired when the user checks or unchecks an option. It receives a new array
containing the updated selected values.

```tsx example
function Example() {
  let [selected, setSelected] = React.useState(['soccer', 'baseball']);

  return (
    <MyCheckboxGroup label="Favorite sports (controlled)" value={selected} onChange={setSelected}>
      <MyCheckbox value="soccer">Soccer</MyCheckbox>
      <MyCheckbox value="baseball">Baseball</MyCheckbox>
      <MyCheckbox value="basketball">Basketball</MyCheckbox>
    </MyCheckboxGroup>
  );
}
```

### HTML forms

CheckboxGroup supports the `name` prop, paired with the Checkbox `value` prop, for integration with HTML forms.

```tsx example
<MyCheckboxGroup label="Favorite sports" name="sports">
  <MyCheckbox value="soccer">Soccer</MyCheckbox>
  <MyCheckbox value="baseball">Baseball</MyCheckbox>
  <MyCheckbox value="basketball">Basketball</MyCheckbox>
</MyCheckboxGroup>
```

## Validation

CheckboxGroup supports the `isRequired` prop to ensure the user selects at least one item, as well as custom client and server-side validation. Individual checkboxes also support validation, and errors from all checkboxes are aggregated at the group level. CheckboxGroup can also be integrated with other form libraries. See the [Forms](forms.html) guide to learn more.

### Group validation

The `isRequired` prop at the `CheckboxGroup` level requires that at least one item is selected. To display validation errors, add a `<FieldError>` element as a child of the CheckboxGroup. This allows you to render error messages from all of the above sources with consistent custom styles.

```tsx example
import {Form, FieldError, Button} from 'react-aria-components';

<Form>
  {/*- begin highlight -*/}
  <CheckboxGroup name="condiments" isRequired>
  {/*- end highlight -*/}
    <Label>Sandwich condiments</Label>
    <MyCheckbox value="lettuce">Lettuce</MyCheckbox>
    <MyCheckbox value="tomato">Tomato</MyCheckbox>
    <MyCheckbox value="onion">Onion</MyCheckbox>
    <MyCheckbox value="sprouts">Sprouts</MyCheckbox>
    {/*- begin highlight -*/}
    <FieldError />
    {/*- end highlight -*/}
  </CheckboxGroup>
  <Button type="submit">Submit</Button>
</Form>
```

<details>
  <summary style={{fontWeight: 'bold'}}><ChevronRight size="S" /> Show CSS</summary>

```css
.react-aria-CheckboxGroup {
  .react-aria-FieldError {
    font-size: 12px;
    color: var(--invalid-color);
  }
}
```

</details>

By default, `FieldError` displays default validation messages provided by the browser. See [Customizing error messages](forms.html#customizing-error-messages) in the Forms guide to learn how to provide your own custom errors.

### Individual Checkbox validation

To require that specific checkboxes are checked, set the `isRequired` prop at the `Checkbox` level instead of the `CheckboxGroup`. The following example shows how to require that all items are selected.

```tsx example
<Form>
  <CheckboxGroup>
    <Label>Agree to the following</Label>
    {/*- begin highlight -*/}
    <MyCheckbox value="terms" isRequired>Terms and conditions</MyCheckbox>
    <MyCheckbox value="privacy" isRequired>Privacy policy</MyCheckbox>
    <MyCheckbox value="cookies" isRequired>Cookie policy</MyCheckbox>
    {/*- end highlight -*/}
    <FieldError />
  </CheckboxGroup>
  <Button type="submit">Submit</Button>
</Form>
```

### Description

The `description` slot can be used to associate additional help text with a checkbox group.

```tsx example
<CheckboxGroup>
  <Label>Pets</Label>
  <MyCheckbox value="dogs">Dogs</MyCheckbox>
  <MyCheckbox value="cats">Cats</MyCheckbox>
  <MyCheckbox value="dragons">Dragons</MyCheckbox>
  <Text slot="description">Select your pets.</Text>
</CheckboxGroup>
```

<details>
  <summary style={{fontWeight: 'bold'}}><ChevronRight size="S" /> Show CSS</summary>

```css
.react-aria-CheckboxGroup {
  [slot=description] {
    font-size: 12px;
  }
}
```

</details>

## Disabled

The entire CheckboxGroup can be disabled with the `isDisabled` prop.

```tsx example
<MyCheckboxGroup label="Favorite sports" isDisabled>
  <MyCheckbox value="soccer">Soccer</MyCheckbox>
  <MyCheckbox value="baseball">Baseball</MyCheckbox>
  <MyCheckbox value="basketball">Basketball</MyCheckbox>
</MyCheckboxGroup>
```

To disable an individual checkbox, pass `isDisabled` to the `Checkbox` instead.

```tsx example
<MyCheckboxGroup label="Favorite sports">
  <MyCheckbox value="soccer">Soccer</MyCheckbox>
  <MyCheckbox value="baseball" isDisabled>Baseball</MyCheckbox>
  <MyCheckbox value="basketball">Basketball</MyCheckbox>
</MyCheckboxGroup>
```

### Read only

The `isReadOnly` prop makes the selection immutable. Unlike `isDisabled`, the CheckboxGroup remains focusable.
See the [MDN docs](https://developer.mozilla.org/en-US/docs/Web/HTML/Attributes/readonly) for more information.

```tsx example
<MyCheckboxGroup label="Favorite sports" defaultValue={['baseball']} isReadOnly>
  <MyCheckbox value="soccer">Soccer</MyCheckbox>
  <MyCheckbox value="baseball">Baseball</MyCheckbox>
  <MyCheckbox value="basketball">Basketball</MyCheckbox>
</MyCheckboxGroup>
```

## Props

### CheckboxGroup

<PropTable component={docs.exports.CheckboxGroup} links={docs.links} />

### Checkbox

Within a `<CheckboxGroup>`, most `<Checkbox>` props are set automatically. The `value` prop is required to identify the checkbox within the group.

<details>
  <summary style={{fontWeight: 'bold'}}><ChevronRight size="S" /> Show props</summary>

<PropTable component={docs.exports.Checkbox} links={docs.links} />

</details>

### Text

`<Text>` accepts all HTML attributes.

### FieldError

A `<FieldError>` displays validation errors.

<details>
  <summary style={{fontWeight: 'bold'}}><ChevronRight size="S" /> Show props</summary>

<PropTable component={docs.exports.FieldError} links={docs.links} />

</details>

## Styling

React Aria components can be styled in many ways, including using CSS classes, inline styles, utility classes (e.g. Tailwind), CSS-in-JS (e.g. Styled Components), etc. By default, all components include a builtin `className` attribute which can be targeted using CSS selectors. These follow the `react-aria-ComponentName` naming convention.

```css
.react-aria-CheckboxGroup {
  /* ... */
}
```

A custom `className` can also be specified on any component. This overrides the default `className` provided by React Aria with your own.

```jsx
<Checkbox className="my-checkbox">
  {/* ... */}
</Checkbox>
```

In addition, some components support multiple UI states (e.g. focused, placeholder, readonly, etc.). React Aria components expose states using data attributes, which you can target in CSS selectors. For example:

```css
.react-aria-Checkbox[data-selected] {
  /* ... */
}
```

The `className` and `style` props also accept functions which receive states for styling. This lets you dynamically determine the classes or styles to apply, which is useful when using utility CSS libraries like [Tailwind](https://tailwindcss.com/).

```jsx
<Checkbox className={({isPressed}) => isPressed ? 'bg-gray-700' : 'bg-gray-600'} />
```

Render props may also be used as children to alter what elements are rendered based on the current state. For example, you could render an extra element when the checkbox is selected.

```jsx
<Checkbox>
  {({isSelected}) => (
    <>
      {isSelected && <CheckIcon />}
      Subscribe
    </>
  )}
</Checkbox>
```

The states and selectors for each component used in a `CheckboxGroup` are documented below.

### CheckboxGroup

A `CheckboxGroup` can be targeted with the `.react-aria-CheckboxGroup` CSS selector, or by overriding with a custom `className`. It supports the following states and render props:

<StateTable properties={docs.exports.CheckboxGroupRenderProps.properties} />

### Checkbox

A `Checkbox` can be targeted with the `.react-aria-Checkbox` CSS selector, or by overriding with a custom `className`. It supports the following states:

<StateTable properties={docs.exports.CheckboxRenderProps.properties} />

### Text

The help text elements within a `CheckboxGroup` can be targeted with the `[slot=description]` and `[slot=errorMessage]` CSS selectors, or by adding a custom `className`.

### FieldError

A `FieldError` can be targeted with the `.react-aria-FieldError` CSS selector, or by overriding with a custom `className`. It supports the following render props:

<StateTable properties={docs.exports.FieldErrorRenderProps.properties} />

## Advanced customization

### Contexts

All React Aria Components export a corresponding context that can be used to send props to them from a parent element. This enables you to build your own compositional APIs similar to those found in React Aria Components itself. You can send any prop or ref via context that you could pass to the corresponding component. The local props and ref on the component are merged with the ones passed via context, with the local props taking precedence (following the rules documented in [mergeProps](mergeProps.html)).

The components in a CheckboxGroup support the following contexts:

<ContextTable components={['CheckboxGroup', 'Checkbox']} docs={docs} />

This example shows a `CheckboxDescription` component that accepts a checkbox in its children and renders a description element below it. It uses the [useId](useId.html) hook to generate a unique id for the description, and associates it with the checkbox via the `aria-describedby` attribute passed to the `CheckboxContext` provider.

```tsx example
import {CheckboxContext} from 'react-aria-components';
import {useId} from 'react-aria';

interface CheckboxDescriptionProps {
  children?: React.ReactNode,
  description?: string
}

function CheckboxDescription({children, description}: CheckboxDescriptionProps) {
  let descriptionId = useId();
  return (
    <div>
      {/*- begin highlight -*/}
      <CheckboxContext.Provider value={{'aria-describedby': descriptionId}}>
      {/*- end highlight -*/}
        {children}
      </CheckboxContext.Provider>
      <small id={descriptionId}>{description}</small>
    </div>
  );
}

<MyCheckboxGroup label="Email settings" defaultValue={['newsletter', 'deals', 'notifications']}>
  <CheckboxDescription description="Receive our newsletter once per week.">
    <MyCheckbox value="newsletter">Newsletter</MyCheckbox>
  </CheckboxDescription>
  <CheckboxDescription description="The best deals and sales for members.">
    <MyCheckbox value="deals">Deals</MyCheckbox>
  </CheckboxDescription>
  <CheckboxDescription description="Notifications about your orders.">
    <MyCheckbox value="notifications">Notifications</MyCheckbox>
  </CheckboxDescription>
</MyCheckboxGroup>
```

### Custom children

CheckboxGroup passes props to its child components, such as the label, via their associated contexts. These contexts are exported so you can also consume them in your own custom components. This enables you to reuse existing components from your app or component library together with React Aria Components.

<ContextTable components={['Label', 'Text']} docs={docs} />

This example consumes from `LabelContext` in an existing styled label component to make it compatible with React Aria Components. The <TypeLink links={docs.links} type={docs.exports.useContextProps} /> hook merges the local props and ref with the ones provided via context by CheckboxGroup.

```tsx
import type {LabelProps} from 'react-aria-components';
import {LabelContext, useContextProps} from 'react-aria-components';

const MyCustomLabel = React.forwardRef((props: LabelProps, ref: React.ForwardedRef<HTMLLabelElement>) => {
  // Merge the local props and ref with the ones provided via context.
  ///- begin highlight -///
  [props, ref] = useContextProps(props, ref, LabelContext);
  ///- end highlight -///

  // ... your existing Label component
  return <label {...props} ref={ref} />;
});
```

Now you can use `MyCustomLabel` within a `CheckboxGroup`, in place of the builtin React Aria Components `Label`.

```tsx
<CheckboxGroup>
  {/*- begin highlight -*/}
  <MyCustomLabel>Favorite sports</MyCustomLabel>
  {/*- end highlight -*/}
  <MyCheckbox value="soccer">Soccer</MyCheckbox>
  <MyCheckbox value="baseball">Baseball</MyCheckbox>
  <MyCheckbox value="basketball">Basketball</MyCheckbox>
</CheckboxGroup>
```

### State

CheckboxGroup provides a <TypeLink links={statelyDocs.links} type={statelyDocs.exports.CheckboxGroupState} /> object to its children via `CheckboxGroupStateContext`. This can be used to access and manipulate the checkbox group's state.

This example shows a `SelectionCount` component that can be placed within a `CheckboxGroup` to display the number of selected items.

```tsx example
import {CheckboxGroupStateContext} from 'react-aria-components';

function SelectionCount() {
  /*- begin highlight -*/
  let state = React.useContext(CheckboxGroupStateContext)!;
  /*- end highlight -*/
  return <small>{state.value.length} items selected.</small>;
}

<MyCheckboxGroup label="Sandwich condiments">
  <MyCheckbox value="lettuce">Lettuce</MyCheckbox>
  <MyCheckbox value="tomato">Tomato</MyCheckbox>
  <MyCheckbox value="onion">Onion</MyCheckbox>
  <MyCheckbox value="sprouts">Sprouts</MyCheckbox>
  <SelectionCount />
</MyCheckboxGroup>
```

### Hooks

If you need to customize things further, such as accessing internal state or customizing DOM structure, you can drop down to the lower level Hook-based API. See [useCheckboxGroup](useCheckboxGroup.html) for more details.
