Access lifecycle methods without a class or a component state
npm install react-functional-lifecycleAre you tired of using classes in React just to use the lifecycle methods? This library is designed to allow lifecycle methods to be exposed as composable functions.
Previously:
``javascript
class MyComponent {
componentDidMount () {
console.log('I mounted with props:', this.props);
}
componentWillUnmount () {
console.log('See you later!', this.props);
}
getSnapshotBeforeUpdate () {
return 'I am a snapshot!';
}
componentDidUpdate (prevProps, prevState, snapshot) {
console.log('Check out my snapshot: ', snapshot);
}
render () {
return (
);
}
}
`
With React-Functional-LifeCycle:
`javascript
const componentMount = props => {
console.log('I mounted with props:', props);
};
const getSnapshot = () => (
'I am a snapshot!'
);
const componentUpdate = (props, prevProps, snapshot) => {
console.log('Check out my snapshot: ', snapshot);
};
const componentUnmount = props => {
console.log('See you later!', props);
};
const MyComponent = compose(
componentDidMount(componentMount),
getSnapshotBeforeUpdate(getSnapshot, componentUpdate)
componentWillUnmount(componentUnmount)
)(SomeComponent);
`
This is a way to tap into the React lifecycle methods without writing classes. This is useful if you are using Recompose or Redux to manage your state, but you still need to access lifecycle methods.
This library works with React web or native and allows access to all of the lifecycle methods you know and love.
React Functional Lifecycle has a peerDependency of React 14 or greater. Otherwise, installing it is as easy as:
npm install react-functional-lifecycle --save
- componentWillMount(props, component) deprecated in React 16.3
- UNSAFE_componentWillMount(props, component)
- componentDidMount(props, component)
- componentWillReceiveProps(props, nextProps, component) deprecated in React 16.3
- UNSAFE_componentWillReceiveProps(props, nextProps, component)
- shouldComponentUpdate(props, nextProps, component)
- componentWillUpdate(props, nextProps, component) deprecated in React 16.3
- UNSAFE_componentWillUpdate(props, nextProps, component)
- componentDidUpdate(props, previousProps, component)
- componentWillUnmount(props, component)
- getDerivedStateFromProps(props)
- [getSnapshotBeforeUpdate([props, prevProps, component], [props, prevProps, snapshot, component])](#getsnapshotbeforeupdate)
- componentDidCatch(props, error, info, component)
This is triggered when a component will mount. Note that this method is being deprecated and will not work in version 17 of React. Use UNSAFE_componentWillMount if you must use it now.
componentWillMount(props: Object, component: Object)
`javascript
import { componentWillMount } from 'react-functional-lifecycle';
export default componentWillMount(props => {
console.log('I will mount with props:', props);
})(YourReactComponent);
`
This is triggered when a component will mount.
UNSAFE_componentWillMount(props: Object, component: Object)
`javascript
import { UNSAFE_componentWillMount } from 'react-functional-lifecycle';
export default UNSAFE_componentWillMount(props => {
console.log('I will mount with props:', props);
})(YourReactComponent);
`
This is triggered when the component is about to get new props. Note that this method is being deprecated and will not work in version 17 of React. Use UNSAFE_componentWillReceiveProps if you must use it now.
componentWillReceiveProps(props: Object, component: Object)
`javascript
import { componentWillReceiveProps } from 'react-functional-lifecycle';
export default componentWillReceiveProps(props => {
console.log('I am going to receive props:', props);
})(YourReactComponent);
`
This is triggered when the component is about to get new props.
UNSAFE_componentWillReceiveProps(props: Object, component: Object)
`javascript
import { UNSAFE_componentWillReceiveProps } from 'react-functional-lifecycle';
export default UNSAFE_componentWillReceiveProps(props => {
console.log('I am going to receive props:', props);
})(YourReactComponent);
`
This is triggered after a component mounts.
componenDidMount(props: Object, component: Object)
`javascript
import { componenDidMount } from 'react-functional-lifecycle';
export default componenDidMount(props => {
console.log('I did mount with props:', props);
})(YourReactComponent);
`
Return true to update your component and false to prevent the component from re-rendering.
shouldComponentUpdate(props: Object, nextProps: Object, component: Object)
`javascript
import { shouldComponentUpdate } from 'react-functional-lifecycle';
export default shouldComponentUpdate(
(props, nextProps) => props !== nextProps
)(YourReactComponent);
`
This is triggered when a component will update. Note that this method is being deprecated and will not work in version 17 of React. Use UNSAFE_componentWillUpdate if you must use it now.
componentWillUpdate(props: Object, nextProps: Object, component: Object)
`javascript
import { componentWillUpdate } from 'react-functional-lifecycle';
export default componentWillUpdate((props, nextProps) => {
console.log('I will update with props:', nextProps);
console.log('Here are my current props', props);
})(YourReactComponent);
`
This is triggered when a component will update.
UNSAFE_componentWillUpdate(props: Object, nextProps: Object, component: Object)
`javascript
import { UNSAFE_componentWillUpdate } from 'react-functional-lifecycle';
export default UNSAFE_componentWillUpdate((props, nextProps) => {
console.log('I will update with props:', nextProps);
console.log('Here are my current props', props);
})(YourReactComponent);
`
This is triggered when a component finished an update.
componentDidUpdate(props: Object, prevProps: Object, component: Object)
`javascript
import { componentDidUpdate } from 'react-functional-lifecycle';
export default componentDidUpdate((props, prevProps) => {
console.log('I did update with props:', props);
console.log('Here are my previous props', prevProps);
})(YourReactComponent);
`
This is triggered when a component is about to unmount.
componentWillUnmount(props: Object, component: Object)
`javascript
import { componentWillUnmount } from 'react-functional-lifecycle';
export default componentWillUnmount((props) => {
console.log('I will unmount with props:', props);
})(YourReactComponent);
`
This is invoked after a component is instantiated as well as when it receives new props. It should return an object to update state, or null to indicate that the new props do not require any state updates.
getDerivedStateFromProps(props: Object)
`javascript
import { getDerivedStateFromProps } from 'react-functional-lifecycle';
export default getDerivedStateFromProps((props) => {
return !!props.hasUpdate;
})(YourReactComponent);
`
This method takes two functions: the getSnapshotBeforeUpdate method and the componentDidUpdate method which has access to the snapshot. getSnapshotBeforeUpdate() is invoked right before the most recently rendered output is committed to e.g. the DOM. It enables your component to capture current values (e.g. scroll position) before they are potentially changed. Any value returned by this lifecycle will be passed as a parameter to componentDidUpdate()
getSnapshotBeforeUpdate([props: Object, prevProps: Object, component: Object], [props: Object, prevProps: Object, snapshot: any, component: Object])
`javascript
import { getSnapshotBeforeUpdate } from 'react-functional-lifecycle';
export default getSnapshotBeforeUpdate((props, prevProps) => {
return 'MY SNAPSHOT'
}, (props, prevProps, snapshot) => {
console.log(snapshot); // MY SNAPSHOT
})(YourReactComponent);
`
This is triggered when a component has an error.
componentDidCatch(props: Object, error: any, info: any, component: Object)
`javascript
import { componentDidCatch } from 'react-functional-lifecycle';
export default componentDidCatch((_props, error) => {
console.log('I had an error:', error);
})(YourReactComponent);
`
The composed wrapper usage allows you to string multiple methods together. If you are using a utility library such as Recompose, Lodash or Ramda, you can use compose like this:
`javascript
import { compose } from 'recompose';
import { shouldComponentUpdate } from 'react-functional-lifecycle';
export default compose(
shouldComponentUpdate((props, nextProps) => props !== nextProps),
componentWillUnmount(() => console.log('Bye!'))
)(YourReactComponent);
``
We encourage you to contribute to React Functional Lifecycle by submitting bug reports and pull requests through Github.
React Functional Lifecycle is released under The MIT License (MIT)
Copyright (c) [2018] [Aloompa LLC]
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.