)
```
Render content using the [render-props pattern](https://reactjs.org/docs/render-props.html).
```jsx
const MyComponent = ({ isOpen }) => (
{(state) => (
I know the collapse state: {state}
)}
)
```
#### `render` : function
Render content using the render-props pattern.
```jsx
const MyComponent = ({ isOpen }) => {
const render = (state) => (
I know the collapse state: {state}
)
return
}
```
There are four possible collapse states: `collapsed`, `collapsing`, `expanded`, `expanding`.
#### `className` : string
You can specify a custom className. The default value is `collapse-css-transition`. Remember to add CSS transition if a className is provided.
#### `transition` : string
You can also specify a CSS transition inline by using the `transition` prop.
```jsx
const MyComponent = ({ isOpen, duration = '290ms' }) => (
Paragraph of text
)
```
#### `elementType` : string
You can specify the HTML element type for the collapse component. By default, the element type is a `div` element.
```jsx
const MyComponent = ({ isOpen }) => (
Paragraph of text inside an article element
)
```
#### `collapseHeight` : string
You can specify the collapse height in CSS unit to partially show some content.
```jsx
const MyComponent = ({ isOpen }) => (
A long paragraph of text inside an article element
)
```
#### `onChange` : function
Callback function for when the transition changes.
```jsx
const MyComponent = ({ isOpen }) => {
const onChange = ({ state, style }) => {
/*
state: string = the state of the collapse component.
style: object = styles that are applied to the component.
*/
}
return (
A long paragraph of text inside an article element
)
}
```
#### `onInit` : function
Similar to onChange but only invoked on DOM mounted.
This is an example that starts collapsed and expands on mount.
```jsx
const MyComponent = () => {
const [isOpen, setIsOpen] = React.useState(false)
const onInit = ({ state, style, node }) => {
/*
node: HTMLElement = the DOM node of the component.
*/
setIsOpen(true)
}
return (
A long paragraph of text inside an article element
)
}
```
#### `addState` : boolean
If added, then one of the class names will be appended to the component depending on the state.
```
--c-collapsed
--c-collapsing
--c-expanded
--c-expanding
```
#### `noAnim` : boolean
If added, then there will be no collapse animation. State changes between `collapsed` and `expanded`.
#### `overflowOnExpanded` : boolean
If added, then `overflow: hidden` style will not be added when the state is `expanded`.
#### Custom props
`Collapse` applies custom props such as `aria-` and `data-` attributes to the component's rendered DOM element. For example, this can be used to set the `aria-hidden` attribute:
```jsx
const MyComponent = ({ isOpen }) => (
Paragraph of text
)
```
Or you could specify a specific transitionDuration.
```jsx
const collapseStyles = { transitionDuration: '270ms' }
const MyComponent = ({ isOpen }) => (
Paragraph of text
)
```
## Development
To run development
`npm start`
```bash
git clone [repo]
cd [repo]
npm i
npm start
```
- To develop and play around: `npm start`
- To build the bundle: `npm run build`
# CDN
https://unpkg.com/@kunukn/react-collapse/
```html
```
# NPM
https://www.npmjs.com/package/@kunukn/react-collapse
# Supported browsers
Modern browsers (Edge, Firefox, Chrome, Safari, etc).
# Supported React versions
- React version 16.3+ : use Collapse version 1
- React version 16.8+ : use Collapse version 2+
# Used React 16.3 life-cycles
- **render** (uses the style states to invoke CSS transition)
- **componentDidMount** (initial expanded or collapsed state)
- **getDerivedStateFromProps** (detect if isOpen props have changed and apply a new collapse state)
- **componentDidUpdate** (update style states from the four possible collapse states)
# Used React 16.8+ hooks
- **useState**
- **useEffect**
- **useRef**
- **useCallback**
- **useReducer**
# Design goals
- let the browser handle the animation using CSS height transition
- minimal in file size
- minimalistic API - only have a Collapse component which updates on isOpen props
- flexible - provide your own markup, styling and easing
- interruptible - can be reversed during movement
- inert - when collapsed you should tab over the collapsed component
- availability - from cdn or npm install
- collapsible on height only
# This was created with heavy inspiration from
[https://github.com/SparebankenVest/react-css-collapse](https://github.com/SparebankenVest/react-css-collapse) 🎆
# A version also exists for Vue
https://github.com/kunukn/vue-height-collapsible
