⏱️ A versatile precision timer hook for React. Doubles as a stopwatch.
MIT License
Read the official documentation.
👁️ Live Demo
A React timer hook that calls the provided callback at regular intervals. Can be used as a stopwatch, too.
It's accurate, precise, and includes a rich set of options, functionality, and accessors.
setTimeout()
and Unix times, not ticks.Version 3 of this package features a complete redesign to reduce unnecessary renders, plus the addition of a new convenience hook.
React.useCallback()
to optimize render performance. Refer to the Quick Start section below.If this project helped you, please consider buying me a coffee or sponsoring me. Your support is much appreciated!
npm i react-use-precision-timer
import { useTimer } from "react-use-precision-timer";
In your function component:
const callback = React.useCallback(() => console.log('Boom'), []);
// The callback will be called every 1000 milliseconds.
const timer = useTimer({ delay: 1000 }, callback);
In a handler or effect:
timer.start();
The following functions can be used to control the Timer:
timer.start()
- Start the timer. If already started, will restart the timer. You can optionally pass a start time in Unix epoch milliseconds.timer.stop()
- Stop the timer.timer.pause()
- Pause the timer.timer.resume()
- Resume the timer.Refer to Timer for all available functions, including getters for elapsed times.
If you'd like to run a callback after a one-time delay, use the helper hook useDelay:
import { useDelay } from 'react-use-precision-timer';
In your function component:
const callback = React.useCallback(() => console.log('Boom'), []);
// Will call once after 1000ms.
const onceTimer = useDelay(1000, callback);
In a handler or effect:
onceTimer.start();
This will call the callback after the provided 1000 millisecond delay only once.
The timer also functions as a stopwatch when no delay is provided. You can use the helper hook useStopwatch:
import { useStopwatch } from "react-use-precision-timer";
const stopwatch = useStopwatch();
Use start()
, stop()
, pause()
, and resume()
to control the stopwatch.
Stopwatch is a Timer object. Refer to Timer's getters to retrieve elapsed running time, paused time, and so forth.
Calling start while a stopwatch is already running will restart it.
For convenience, the useMomentaryBool hook has been included to momentarily toggle a boolean. This wraps the useDelay hook.
This is very useful for momentary notifications, such as a copy button that shows a momentary checkmark to indicate the operation succeeded.
import { useMomentaryBool } from 'react-use-precision-timer';
In your function component:
// Toggle to true, then back to false after 1000ms.
const [value, toggle] = useMomentaryBool(false, 1000);
Calling toggle()
will set the boolean to true
, then back to false
after a 1000 millisecond delay.
See useTimer for all other hook options and timer functions.
Type definitions have been included for TypeScript support.
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Open source software is awesome and so are you. 😎
Feel free to submit a pull request for bugs or additions, and make sure to update tests as appropriate. If you find a mistake in the docs, send a PR! Even the smallest changes help.
For major changes, open an issue first to discuss what you'd like to change.
If you found this project helpful, let the community know by giving it a star: 👉⭐
See LICENSE.md.