EricLambrecht
What's this?!
This is a very little package with React hooks wrapping time-related vanilla Javascript functions, so you can use them with minimal effort in your React apps without having to worry about manual clean up, or writing boilerplate to pause/resume intervals etc.
Feature Overview
- Hooks for all timing-related vanilla JS functions like:
- setInterval() –> useInterval() | MDN
- setTimeout() –> useTimeout() | MDN
- requestAnimationFrame() –> useAnimationFrame() | MDN
- requestIdleCallback() –> useIdleCallback() | MDN
- …and additional utility hooks for common tasks like
- throttling:
useThrottledState(),useThrottle(),useDebounce() - GFX/animation/rendering:
useAnimationFrameLoop() - reactive counters:
useCounter(),useCountdown(),useTimer() - time:
useClock() - async effects:
useTimeoutEffect(),useIdleCallbackEffect() - oscillation:
useOscillator()
- throttling:
- Reactive intervals: intervals can be controlled via pause, resume, start or stop
- A versatile API: customizable settings, many hook "flavors" depending on the use-case.
- Automatic clean-ups of pending timers, intervals etc. on unmount
- Callbacks are automatically memoized
- Full Typescript support
- Very lightweight (no transitive dependencies!)
- Tree-shakable — You only bundle what you use!
Installation
# via npm
npm i react-timing-hooks
# via yarn
yarn add react-timing-hooksDocumentation
https://ericlambrecht.github.io/react-timing-hooks/
How to migrate
https://ericlambrecht.github.io/react-timing-hooks/migrations/
Some Examples
A "status logger" with useInterval()
`jsx harmony
import { useInterval } from 'react-timing-hooks'
const StatusLogger = () => { const logUpdates = () => console.log('status update') // could also be intialized with { startOnMount: true } to immediately start the interval const { start, pause, resume, isPaused } = useInterval(logUpdates, 1000)
return
----
#### Throttle a button click with `useThrottle()`
```jsx harmony
import { useThrottle } from 'react-timing-hooks'
const HelloWorld = () => {
const [result, setResult] = useState(null)
const updateResult = () => setResult(extremeMegaCalculation())
const onButtonClick = useThrottle(updateResult, 1000)
return <div>
<button onClick={onButtonClick}>Spam me!</button>
<p>Result: {result}</p>
</div>
}Display the user's browsing time using useTimer()
`jsx harmony
import { useTimer } from 'react-timing-hooks'
const BrowsingTime = () => { const [elapsedSeconds] = useTimer(0, { startOnMount: true }) return You've been browsing this page for {elapsedSeconds} seconds. }
----
#### Display the current time with `useClock()`
```jsx harmony
import { useTimeout } from 'react-timing-hooks'
const Clock = () => {
// This will show a time like 1:13:56 PM (supports localized formats as well).
// The displayed time will update every second
const [currentTime] = useClock()
return <span>{currentTime}</span>
}A canvas renderer using useAnimationFrameLoop()
`jsx harmony
import { useAnimationFrameLoop } from 'react-timing-hooks'
const Renderer = () => { const delta = useRef(0) const canvasRef = useRef(null) const canvas = canvasRef.current const context = canvas.getContext('2d')
const updateCanvas = (d) => { context.fillStyle = '#000000' context.fillRect(d, d, context.canvas.width, context.canvas.height) }
const { start, stop, isStopped } = useAnimationFrameLoop(() => { delta.current += 1 updateCanvas(delta.current) })
return <> <canvas ref={canvasRef} {...props}/> <button onClick={isStopped ? start : stop}> {isStopped ? "Start rendering" : "Stop rendering"} </button> </> }
## Why does this exist?
I was once working for a company where the project required lots of timeouts and such. I quickly noticed that
writing a timeout or anything similar requires a lot of **boilerplate** (if you don't do it quick and dirty).
Dan Abramov showcased this in [one of his blogposts](https://overreacted.io/making-setinterval-declarative-with-react-hooks/) a while a go.
This library is supposed to give you easy access to those time-related functionalities while keeping your code clean and concise.
You will **not** have to manually clean up timers or intervals.
Another common use-case is pausing/resuming or starting/stopping intervals (or loops). This lib offers
callbacks for that. So pausing is really just a matter of calling a `pause()` function for example.
Many frequent use cases also have their own utility hook, like `useThrottle`, `useCountdown` or `useAnimationFrameLoop`
to make things even easier.
Needless to say, every hook is already tested and typed (so you don't have to).
### Some "Before-/After-Code"
A simple interval that increments a counter on every second and can be manually started upon user input:
#### Before
```jsx harmony
import { useEffect, useState } from 'react'
const Counter = () => {
const [counter, setCounter] = useState(0)
const [startInterval, setStartInterval] = useState(false)
const intervalId = useRef(null)
useEffect(() => {
if (startInterval) {
intervalId.current = setInterval(() => setCounter(c => c + 1), 1000)
}
}, [startInterval])
useEffect(() => {
return function onUnmount() {
if (intervalId.current !== null) {
clearInterval(intervalId.current)
}
}
}, [intervalId])
return <>
<button onClick={() => setStartInterval(true)}>Start counting</button>
<p>{counter}</p>
</>
}After
`jsx harmony
import { useState } from 'react'
import { useInterval } from 'react-timing-hooks'
const Counter = () => { const [counter, setCounter] = useState(0)
const { start } = useInterval(() => setCounter(c => c + 1), 1000)
return <> <button onClick={start}>Start counting</button>
{counter}
</> }
Well,… actually, there is even a shorter way using the utility hook `useTimer()` 🙈
#### After After
```jsx harmony
import { useCounter } from 'react-timing-hooks'
const Counter = () => {
const [counter, { start }] = useTimer(0)
return <>
<button onClick={start}>Start counting</button>
<p>{counter}</p>
</>
}Another example: You might have a timeout that runs under a certain condition. In this case a cleanup
has to be done in a separate useEffect call that cleans everything up (but only on unmount).
Before
`jsx harmony
import { useEffect } from 'react'
const TimeoutRenderer = ({ depA, depB }) => { const [output, setOutput] = useState(null) const timeoutId = useRef(null)
useEffect(() => { if (depA && depB) { timeoutId.current = setTimeout(() => setOutput('Hello World'), 1000) } }, [depA, depB])
useEffect(() => { return function onUnmount() { if (timeoutId.current !== null) { clearTimeout(timeoutId.current) } } }, [timeoutId])
return output ? (
#### After
```jsx harmony
import { useState } from 'react'
import { useTimeoutEffect } from 'react-timing-hooks'
const TimeoutRenderer = ({ depA, depB }) => {
const [output, setOutput] = useState(null)
useTimeoutEffect((timeout, clearAll) => {
if (depA && depB) {
timeout(() => setOutput('Hello World'), 1000)
}
// you could even add more timeouts in this effect
// without any more boilerplate
}, [depA, depB])
return output ? (
<div>{output}</div>
) : null
}In this case react-timing-hooks automatically took care of cleaning up the timeout for you (if the component is mounted for less than a second for instance).
Memoization
You don't have to worry about memoization of your callbacks (by using useCallback) for example. React Timing Hooks is taking care of that for you. So even if you pass a simple inline arrow function to one of these hooks, the return value (if there is one) will not change on every render but instead stay the same (i.e. it will be memoized).
This means something like this is safe to do:
const [foo, setFoo] = useState(null)
const onFooChange = useTimeout(() => console.log('foo changed one second ago!'), 1000)
// the following effect will run only when "foo" changes, just as expected.
// "onFooChange" is memoized and safe to use in a dependency array.
useEffect(() => {
onFooChange()
}, [foo, onFooChange])Bundle Size
The whole lib is tree-shakable, i.e. only hooks you actually use end up in your bundle. So far, we also do not use any transitive dependencies. So don't worry about the bundle size.
But check for yourself: https://bundlephobia.com/result?p=react-timing-hooks
Contributing
see CONTRIBUTING.md