@accessible/disclosure/README.md

🅰 An accessible and versatile disclosure component for React

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<div align="center">
  <h1 align="center">
    &lt;Disclosure&gt;
  </h1>
</div>

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<pre align="center">npm i @accessible/disclosure</pre>
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An accessible and versatile disclosure component for React

## Features

- [x] **Style-agnostic** You can use this component with the styling library of your choice. It
      works with CSS-in-JS, SASS, plain CSS, plain `style` objects, anything!
- [x] **Portal-friendly** The disclosure target will render into React portals of your choice when configured
      to do so.
- [x] **a11y/aria-compliant** This component works with screen readers out of the box and manages
      focus for you.

## Quick Start

[Check out the example on **CodeSandbox**](https://codesandbox.io/s/accessibledisclosure-example-8pkd2)

```jsx harmony
import * as React from 'react'
import * as Disclosure from '@accessible/disclosure'

const Component = () => (
  <Disclosure.Disclosure>
    <Disclosure.Trigger>
      <button>Open me</button>
    </Disclosure.Trigger>

    <Disclosure.Target>
      <div className='my-disclosure'>
        <Disclosure.CloseButton>
          <button>Close me</button>
        </Disclosure.CloseButton>

        <div>I've been disclosed!</div>
      </div>
    </Disclosure.Target>
  </Disclosure.Disclosure>
)
```

## API

### Components

| Component                       | Description                                                                                                        |
| ------------------------------- | ------------------------------------------------------------------------------------------------------------------ |
| [`<Disclosure>`](#disclosure)   | This component creates the context for your disclosure target and trigger and contains some configuration options. |
| [`<Target>`](#target)           | This component wraps any React element and turns it into a disclosure target.                                      |
| [`<Trigger>`](#trigger)         | This component wraps any React element and turns it into a disclosure trigger.                                     |
| [`<CloseButton>`](#closebutton) | This is a convenience component that wraps any React element and adds an onClick handler to close the disclosure.  |  |

### Hooks

| Hook                                                        | Description                                                                                                                                                                      |
| ----------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| [`useDisclosure()`](#usedisclosure)                         | This hook provides the value of the disclosure's [DisclosureContextValue object](#disclosurecontextvalue).                                                                       |
| [`useA11yTarget()`](#usea11ytargettarget-options)           | A React hook for creating a headless disclosure target to [WAI-ARIA authoring practices](https://www.w3.org/TR/wai-aria-practices-1.1/examples/disclosure/disclosure-faq.html).  |
| [`useA11yTrigger()`](#usea11ytriggertarget-options)         | A React hook for creating a headless disclosure trigger to [WAI-ARIA authoring practices](https://www.w3.org/TR/wai-aria-practices-1.1/examples/disclosure/disclosure-faq.html). |
| [`useA11yCloseButton()`](#usea11yclosebuttontarget-options) | A React hook for creating a headless close button to [WAI-ARIA authoring practices](https://www.w3.org/TR/wai-aria-practices-1.1/examples/disclosure/disclosure-faq.html).       |

### &lt;Disclosure&gt;

This component creates the context for your disclosure target and trigger and contains some
configuration options.

#### Props

| Prop        | Type                      | Default     | Required? | Description                                                                                                                                               |
| ----------- | ------------------------- | ----------- | --------- | --------------------------------------------------------------------------------------------------------------------------------------------------------- |
| defaultOpen | `boolean`                 | `false`     | No        | This sets the default open state of the disclosure. By default the disclosure is closed.                                                                  |
| open        | `boolean`                 | `undefined` | No        | This creates a controlled disclosure component where the open state of the disclosure is controlled by this property.                                     |
| onChange    | `(open: boolean) => void` | `undefined` | No        | This callback is invoked any time the `open` state of the disclosure changes.                                                                             |
| id          | `string`                  | `undefined` | No        | By default this component creates a unique id for you, as it is required for certain aria attributes. Supplying an id here overrides the auto id feature. |
| children    | `React.ReactNode`         | `undefined` | No        | Your disclosure contents and any other children.                                                                                                          |

### useA11yTarget(target, options?)

A React hook for creating a headless disclosure target to [WAI-ARIA authoring practices](https://www.w3.org/TR/wai-aria-practices-1.1/examples/disclosure/disclosure-faq.html).

#### Arguments

| Argument | Type                                               | Required? | Description                 |
| -------- | -------------------------------------------------- | --------- | --------------------------- |
| target   | <code>React.RefObject&lt;T&gt; \| T \| null</code> | Yes       | A React ref or HTML element |
| options  | [`UseA11yTargetOptions`](#usea11ytargetoptions)    | No        | Configuration options       |

#### UseA11yTargetOptions

```ts
export interface UseA11yTargetOptions {
  /**
   * Adds this class name to props when the disclosure is open
   */
  openClass?: string
  /**
   * Adds this class name to props when the disclosure is closed
   */
  closedClass?: string
  /**
   * Adds this style to props when the disclosure is open
   */
  openStyle?: React.CSSProperties
  /**
   * Adds this style to props when the disclosure is closed
   */
  closedStyle?: React.CSSProperties
  /**
   * Prevents the `window` from scrolling when the target is
   * focused after opening.
   */
  preventScroll?: boolean
  /**
   * When `true`, this closes the target element when the `Escape`
   * key is pressed.
   * @default true
   */
  closeOnEscape?: boolean
}
```

#### Returns

```ts
interface A11yProps {
  readonly 'aria-hidden': boolean
  readonly id: string | undefined
  readonly className: string | undefined
  readonly style: {
    visibility: 'visible' | 'hidden'
  } & React.CSSProperties
}
```

#### Example

```jsx harmony
import * as React from 'react'
import {useA11yTarget} from '@accessible/disclosure'

const MyTarget = () => {
  const ref = React.useRef(null)
  const a11yProps = useA11yTarget(ref, {preventScroll: true})

  return (
    <div ref={ref} {...a11yProps}>
      I am the disclosure content
    </div>
  )
}
```

### &lt;Target&gt;

This component wraps any React element and turns it into a disclosure target.

#### Props

| Prop          | Type                                              | Default     | Required? | Description                                                                                                                                                                                                         |
| ------------- | ------------------------------------------------- | ----------- | --------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| portal        | <code>boolean \| string \| PortalizeProps </code> | `false`     | No        | When `true` this will render the disclosure into a React portal with the id `#portals`. You can render it into any portal by providing its query selector here, e.g. `#foobar`, `[data-portal=true]`, or `.foobar`. |
| closeOnEscape | `boolean`                                         | `true`      | No        | By default the disclosure will close when the `Escape` key is pressed. You can turn this off by providing `false` here.                                                                                             |
| closedClass   | `string`                                          | `undefined` | No        | This class name will be applied to the child element when the disclosure is `closed`.                                                                                                                               |
| openClass     | `string`                                          | `undefined` | No        | This class name will be applied to the child element when the disclosure is `open`.                                                                                                                                 |
| closedStyle   | `React.CSSProperties`                             | `undefined` | No        | These styles will be applied to the child element when the disclosure is `closed` in addition to the default styles that set the target's visibility.                                                               |
| openStyle     | `React.CSSProperties`                             | `undefined` | No        | These styles name will be applied to the child element when the disclosure is `open` in addition to the default styles that set the target's visibility.                                                            |
| preventScroll | `boolean`                                         | `false`     | No        | When `true` this will prevent your browser from scrolling the document to bring the newly-focused tab into view.                                                                                                    |
| children      | `React.ReactElement`                              | `undefined` | Yes       | The child is cloned by this component and has aria attributes injected into its props as well as the events defined above.                                                                                          |

#### Example

```jsx harmony
<Target>
  <div className='alert'>Alert</div>
</Target>

// <div
//   class="alert"
//   aria-hidden="true"
//   id="🅰12"
//   style="visibility: hidden;"
// >
//   Alert
// </div>
```

### useA11yTrigger(target, options?)

A React hook for creating a headless disclosure trigger to [WAI-ARIA authoring practices](https://www.w3.org/TR/wai-aria-practices-1.1/examples/disclosure/disclosure-faq.html).
In addition to providing accessibility props to your component, this hook will add events
for interoperability between actual <button> elements and fake ones e.g. <a> and <div> to the
target element

#### Arguments

| Argument | Type                                               | Required? | Description                 |
| -------- | -------------------------------------------------- | --------- | --------------------------- |
| target   | <code>React.RefObject&lt;T&gt; \| T \| null</code> | Yes       | A React ref or HTML element |
| options  | [`UseA11yTriggerOptions`](#usea11ytriggeroptions)  | No        | Configuration options       |

#### UseA11yTriggerOptions

```ts
export interface UseA11yTriggerOptions {
  /**
   * Adds this class name to props when the disclosure is open
   */
  openClass?: string
  /**
   * Adds this class name to props when the disclosure is closed
   */
  closedClass?: string
  /**
   * Adds this style to props when the disclosure is open
   */
  openStyle?: React.CSSProperties
  /**
   * Adds this style to props when the disclosure is closed
   */
  closedStyle?: React.CSSProperties
  /**
   * Adds an onClick handler in addition to the default one that
   * toggles the disclosure's open state.
   */
  onClick?: (e: MouseEvent) => any
}
```

#### Returns

```ts
interface A11yProps {
  readonly 'aria-controls': string | undefined
  readonly 'aria-expanded': boolean
  readonly role: 'button'
  readonly tabIndex: 0
  readonly className: string | undefined
  readonly style: React.CSSProperties | undefined
}
```

#### Example

```jsx harmony
import * as React from 'react'
import {useA11yTrigger} from '@accessible/disclosure'

const MyTrigger = () => {
  const ref = React.useRef(null)
  const a11yProps = useA11yTrigger(ref, {
    openClass: 'open',
    closedClass: 'closed',
  })

  return (
    <button ref={ref} {...a11yProps}>
      Clicking me toggles the disclosure content
    </button>
  )
}
```

### &lt;Trigger&gt;

This component wraps any React element and adds an `onClick` handler which toggles the open state
of the disclosure target.

#### Props

| Prop        | Type                  | Default     | Required? | Description                                                                                                                |
| ----------- | --------------------- | ----------- | --------- | -------------------------------------------------------------------------------------------------------------------------- |
| closedClass | `string`              | `undefined` | No        | This class name will be applied to the child element when the disclosure is `closed`.                                      |
| openClass   | `string`              | `undefined` | No        | This class name will be applied to the child element when the disclosure is `open`.                                        |
| closedStyle | `React.CSSProperties` | `undefined` | No        | These styles will be applied to the child element when the disclosure is `closed`.                                         |
| openStyle   | `React.CSSProperties` | `undefined` | No        | These styles name will be applied to the child element when the disclosure is `open`.                                      |
| children    | `React.ReactElement`  | `undefined` | Yes       | The child is cloned by this component and has aria attributes injected into its props as well as the events defined above. |

```jsx harmony
<Trigger on='click'>
  <button className='my-button'>Open me!</button>
</Trigger>

// <button
//   class="my-button"
//   aria-controls="🅰12"
//   aria-expanded="false"
// >
//   Open me!
// </button>
```

### useA11yCloseButton(target, options?)

A React hook for creating a headless close button to [WAI-ARIA authoring practices](https://www.w3.org/TR/wai-aria-practices-1.1/examples/disclosure/disclosure-faq.html).
In addition to providing accessibility props to your component, this hook will add events
for interoperability between actual <button> elements and fake ones e.g. <a> and <div> to the
target element

#### Arguments

| Argument | Type                                                      | Required? | Description                 |
| -------- | --------------------------------------------------------- | --------- | --------------------------- |
| target   | <code>React.RefObject&lt;T&gt; \| T \| null</code>        | Yes       | A React ref or HTML element |
| options  | [`UseA11yCloseButtonOptions`](#usea11yclosebuttonoptions) | No        | Configuration options       |

#### UseA11yCloseButtonOptions

```ts
export interface UseA11yCloseButtonOptions {
  /**
   * Adds an onClick handler in addition to the default one that
   * closes the disclosure.
   */
  onClick?: (e: MouseEvent) => any
}
```

#### Returns

```ts
interface A11yProps {
  readonly 'aria-controls': string | undefined
  readonly 'aria-expanded': boolean
  readonly 'aria-label': 'Close'
  readonly role: 'button'
  readonly tabIndex: 0
}
```

#### Example

```jsx harmony
import * as React from 'react'
import {useA11yCloseButton} from '@accessible/disclosure'

const MyTrigger = () => {
  const ref = React.useRef(null)
  const a11yProps = useA11yCloseButton(ref, {
    onClick: () => console.log('Closing!'),
  })

  return (
    <button ref={ref} {...a11yProps}>
      Clicking me closes the disclosure content
    </button>
  )
}
```

### &lt;CloseButton&gt;

This is a convenience component that wraps any React element and adds an onClick handler which closes the disclosure.

#### Props

| Prop     | Type                 | Default     | Required? | Description                                                                                                                |
| -------- | -------------------- | ----------- | --------- | -------------------------------------------------------------------------------------------------------------------------- |
| children | `React.ReactElement` | `undefined` | Yes       | The child is cloned by this component and has aria attributes injected into its props as well as the events defined above. |

```jsx harmony
<CloseButton>
  <button className='my-button'>Close me</button>
</CloseButton>

// <button
//   class="my-button"
//   aria-controls="disclosure--12"
//   aria-expanded="false"
// >
//   Close me
// </button>
```

### useDisclosure()

This hook provides the value of the disclosure's [DisclosureContextValue object](#disclosurecontextvalue)

### DisclosureContextValue

```typescript
export interface DisclosureContextValue {
  /**
   * The open state of the disclosure
   */
  isOpen: boolean
  /**
   * Opens the disclosure
   */
  open: () => void
  /**
   * Closes the disclosure
   */
  close: () => void
  /**
   * Toggles the open state of the disclosure
   */
  toggle: () => void
  /**
   * A unique ID for the disclosure target
   */
  id?: string
}
```

#### Example

```jsx harmony
const Component = () => {
  const {open, close, toggle, isOpen} = useDisclosure()
  return <button onClick={toggle}>Toggle the disclosure</button>
}
```

## LICENSE

MIT