<Accordion>
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npm i @accessible/accordion
An accessible and versatile accordion for React with keyboard navigation and labeling features taught in w3.org's WAI-ARIA accordion best practices example.
Features
- Style-agnostic You can use this component with the styling library of your choice. It
style objects, anything!- a11y/aria-compliant This component works with screen readers out of the box and manages
Quick Start
Check out the example on CodeSandbox```jsx harmony import {Accordion, Section, Trigger, Panel} from '@accessible/accordion'
const Component = () => (
<Section>
<h3>
<Trigger>
<button>Section 1</button>
</Trigger>
</h3>
<Panel>
<div className="panel">Section 1 content</div>
</Panel>
</Section>
<Section>
<h3>
<Trigger>
<button>Section 2</button>
</Trigger>
</h3>
<Panel>
<div className="panel">Section 2 content</div>
</Panel>
</Section>## API
### Components
| Component | Description |
| --------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| [`<Accordion>`](#accordion) | This component creates the context for your accordion section and contains some configuration options. |
| [`<Section>`](#section) | This component creates the context for the accordion panel and trigger contained in this section. It must be a direct descendent of [`<Accordion>`](#accordion). |
| [`<Trigger>`](#trigger) | This component clones any React element and turns it into a accordion trigger that controls the visible state of the panel. |
| [`<Panel>`](#panel) | This component clones any React element and turns it into a accordion panel. |
| [`<Close>`](#close) | This is a convenience component that clones any React element and adds an onClick handler to close its parent panel. | |
### Hooks
| Hook | Description |
| --------------------------------- | --------------------------------------------------------------------------------------------------------------------- |
| [`useAccordion()`](#useaccordion) | This hook returns the value of the accordion's [AccordionContext object](#accordioncontextvalue). |
| [`useSection()`](#usesection) | This hook returns the value of the accordion [`<Section>`'s](#section) [SectionContext object](#sectioncontextvalue). |
| [`useControls()`](#usecontrols) | This hook returns the accordion [`<Section>`'s](#section) `open`, `close`, and `toggle` functions. |
| [`useDisabled()`](#usedisabled) | This hook returns the accordion [`<Section>`'s](#section) `disabled` value. |
| [`useIsOpen()`](#useisopen) | This hook returns the accordion [`<Section>`'s](#section) `isOpen` value. |
### `<Accordion>`
This component creates the context for your accordion section and contains some configuration options.
[`<Section>`s](#section) are the only type of children allowed.
#### Props
| Prop | Type | Default | Required? | Description |
| ----------------- | ----------------------------------------------------- | ----------- | --------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| defaultOpen | <code>number | number[]</code> | `undefined` | No | The section by index (or sections if `allowMultipleOpen`) you want opened by default. |
| open | <code>number | number[]</code> | `undefined` | No | Makes this a controlled component where `open`, `close`, `toggle`, controls have no effect. The sections defined here are always the ones that are open. |
| allowMultipleOpen | `boolean` | `false` | No | Allows multiple sections to be opened at one time. |
| allowAllClosed | `boolean` | `false` | No | Allows all of the sections to be closed. If `false`, you must define either the `open` or `defaultOpen` property. |
| onChange | <code>(opened: number | number[]) => void</code> | `undefined` | No | Called each time the open sections change. If `allowMultipleOpen`, the argument will be an array, otherwise a single number. The number corresponds to the open section's index. |
| children | `React.ReactElement<SectionProps>[]` | `undefined` | Yes | The only children allowed by this component are [`<Section>`s](#section). |
### `<Section>`
This component creates the context for the accordion panel and trigger contained in this section. It must be a direct
descendent of [`<Accordion>`](#accordion).
#### Props
| Prop | Type | Default | Required? | Description |
| -------- | --------------------------------------------------------------------------------------- | ----------- | --------- | ---------------------------------------------------------------------------------------------------------------- |
| id | `string` | `undefined` | No | Overrides the ID that is auto-generated by this component. |
| disabled | `boolean` | `false` | No | `true` if the section should not be allowed to have its `open` state changed. |
| children | <code>React.ReactNode | ((context: SectionContextValue) => React.ReactNode)</code> | `undefined` | Yes | Sections must include a [`<Trigger>`](#trigger) and a [`Panel`](#panel) in addition to anything else you'd like. |
### `<Trigger>`
This component clones any React element and turns it into a accordion trigger that controls the visible state of
the [`<Panel>`](#panel). It must be a child of [`<Section>`](#section).
#### Props
| Prop | Type | Default | Required? | Description |
| ----------- | --------------------- | ----------- | --------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| openClass | `string` | `undefined` | No | This class name will be applied to the child element when the section is `open`. |
| closedClass | `string` | `undefined` | No | This class name will be applied to the child element when the section is `closed`. |
| openStyle | `React.CSSProperties` | `undefined` | No | These styles will be applied to the child element when the section is `open`. |
| closedStyle | `React.CSSProperties` | `undefined` | No | These styles will be applied to the child element when the section is `closed`. |
| children | `React.ReactElement` | `undefined` | Yes | The child is cloned by this component and has aria attributes injected into its props as well as keyboard events for opening the section with `space` and `enter` keys and navigating between sections. |
### `<Panel>`
This component clones any React element and turns it into a accordion section panel. It must be
a child of [`<Section>`](#section).
#### Props
| Prop | Type | Default | Required? | Description |
| ----------- | --------------------- | ----------- | --------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| openClass | `string` | `undefined` | No | This class name will be applied to the child element when the section is `open`. |
| closedClass | `string` | `undefined` | No | This class name will be applied to the child element when the section is `closed`. |
| openStyle | `React.CSSProperties` | `undefined` | No | These styles will be applied to the child element when the section is `open`. |
| closedStyle | `React.CSSProperties` | `undefined` | No | These styles will be applied to the child element when the section is `closed`. |
| children | `React.ReactElement` | `undefined` | Yes | The child is cloned by this component and has aria attributes injected into its props as well as keyboard events for closing the section with the `escape` key. |
### `<Close>`
This is a convenience component that clones any React element and adds an onClick handler to close its parent panel. It
must be a child of [`<Section>`](#section).
#### 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 keyboard events to ensure it acts like a button even if it isn't a native `<button>`. |
### `useAccordion()`
This hook returns the value of the accordion's [AccordionContext object](#accordioncontextvalue). This hook
must be within a child of [`<Accordion>`](#accordion).
### `AccordionContextValue`
```typescript jsx
interface AccordionContextValue {
// DOM references to the accordion sections
sections: (HTMLElement | undefined)[]
// Registers a new accordion section
registerSection: (index: number, trigger: HTMLElement) => () => void
// The indexes of the open sections
opened: number[]
// Opens a section
open: (section: number | undefined) => void
// Closes a section
close: (section: number | undefined) => void
// Returns true if a section is open
isOpen: (section: number | undefined) => boolean
// Does the accordion allow all of its sections to be closed?
allowAllClosed: boolean
}useSection()
This hook returns the value of the accordion sections's SectionContextValue object. This hook
must be within a child of <Section>.SectionContextValue
```typescript jsx
interface SectionContextValue {
// Is this section open?
isOpen: boolean
// Opens this section if not disabled
open: () => void
// Closes this section if possible
close: () => void
// Toggles the visible state of this section if possible
toggle: () => void
// The id of this section
id?: string
// The index of this section
index: number
// Is the section disabled?
disabled: boolean
// The DOM reference to the section's
triggerRef: React.MutableRefObject
}
```useControls()
This hook returns the accordion sections's open, close, and toggle functions. This hook
must be within a child of <Section>.useDisabled()
This hook returns the accordion sections's disabled value. This hook
must be within a child of <Section>.useIsOpen()
This hook returns the accordion sections's isOpen value. This hook
must be within a child of <Section>.