readme.md

react-timer-hook

React timer hook is a custom react hook, built to handle timer, stopwatch, and time logic/state in your react component.

1. useTimer: Timers (countdown timer)
2. useStopwatch: Stopwatch (count up timer)
3. useTime: Time (return current time)

---

Setup

yarn add react-timer-hook OR npm install --save react-timer-hook

---

useTimer - Demo

Example

import React from 'react';
import { useTimer } from 'react-timer-hook';

function MyTimer({ expiryTimestamp }) {
  const {
    seconds,
    minutes,
    hours,
    days,
    isRunning,
    start,
    pause,
    resume,
    restart,
  } = useTimer({ expiryTimestamp, onExpire: () => console.warn('onExpire called') });


  return (
    <div style={{textAlign: 'center'}}>
      <h1>react-timer-hook </h1>
      <p>Timer Demo</p>
      <div style={{fontSize: '100px'}}>
        <span>{days}</span>:<span>{hours}</span>:<span>{minutes}</span>:<span>{seconds}</span>
      </div>
      <p>{isRunning ? 'Running' : 'Not running'}</p>
      <button onClick={start}>Start</button>
      <button onClick={pause}>Pause</button>
      <button onClick={resume}>Resume</button>
      <button onClick={() => {
        // Restarts to 5 minutes timer
        const time = new Date();
        time.setSeconds(time.getSeconds() + 300);
        restart(time)
      }}>Restart</button>
    </div>
  );
}

export default function App() {
  const time = new Date();
  time.setSeconds(time.getSeconds() + 600); // 10 minutes timer
  return (
    <div>
      <MyTimer expiryTimestamp={time} />
    </div>
  );
}

Settings

key	Type	Required	Description
expiryTimestamp	Date object	YES	this will define for how long the timer will be running
autoStart	boolean	No	flag to decide if timer should start automatically, by default it is set to true
onExpire	Function	No	callback function to be executed once countdown timer is expired

Values

key	Type	Description
seconds	number	seconds value
minutes	number	minutes value
hours	number	hours value
days	number	days value
isRunning	boolean	flag to indicate if timer is running or not
pause	function	function to be called to pause timer
start	function	function if called after pause the timer will continue based on original expiryTimestamp
resume	function	function if called after pause the timer will continue countdown from last paused state
restart	function	function to restart timer with new expiryTimestamp, accept 2 arguments first is the new expiryTimestamp of type Date object and second is autoStart of type boolean to decide if it should automatically start after restart or not, default is true

---

useStopwatch - Demo

Example

import React from 'react';
import { useStopwatch } from 'react-timer-hook';

function MyStopwatch() {
  const {
    seconds,
    minutes,
    hours,
    days,
    isRunning,
    start,
    pause,
    reset,
  } = useStopwatch({ autoStart: true });


  return (
    <div style={{textAlign: 'center'}}>
      <h1>react-timer-hook</h1>
      <p>Stopwatch Demo</p>
      <div style={{fontSize: '100px'}}>
        <span>{days}</span>:<span>{hours}</span>:<span>{minutes}</span>:<span>{seconds}</span>
      </div>
      <p>{isRunning ? 'Running' : 'Not running'}</p>
      <button onClick={start}>Start</button>
      <button onClick={pause}>Pause</button>
      <button onClick={reset}>Reset</button>
    </div>
  );
}

export default function App() {
  return (
    <div>
      <MyStopwatch />
    </div>
  );
}

Settings

key	Type	Required	Description
autoStart	boolean	No	if set to true stopwatch will auto start, by default it is set to false
offsetTimestamp	Date object	No	this will define the initial stopwatch offset example: const stopwatchOffset = new Date(); stopwatchOffset.setSeconds(stopwatchOffset.getSeconds() + 300); this will result in a 5 minutes offset and stopwatch will start from 0:0:5:0 instead of 0:0:0:0

Values

key	Type	Description
seconds	number	seconds value
minutes	number	minutes value
hours	number	hours value
days	number	days value
isRunning	boolean	flag to indicate if stopwatch is running or not
start	function	function to be called to start/resume stopwatch
pause	function	function to be called to pause stopwatch
reset	function	function to be called to reset stopwatch to 0:0:0:0, you can also pass offset parameter to this function to reset stopwatch with offset, similar to how offsetTimestamp will offset the initial stopwatch time, this function will accept also a second argument which will decide if stopwatch should automatically start after reset or not default is true

---

useTime - Demo

Example

import React from 'react';
import { useTime } from 'react-timer-hook';

function MyTime() {
  const {
    seconds,
    minutes,
    hours,
    ampm,
  } = useTime({ format: '12-hour'});

  return (
    <div style={{textAlign: 'center'}}>
      <h1>react-timer-hook </h1>
      <p>Current Time Demo</p>
      <div style={{fontSize: '100px'}}>
        <span>{hours}</span>:<span>{minutes}</span>:<span>{seconds}</span><span>{ampm}</span>
      </div>
    </div>
  );
}

export default function App() {
  return (
    <div>
      <MyTime />
    </div>
  );
}

Settings

key	Type	Required	Description
format	string	No	if set to 12-hour time will be formatted with am/pm

Values

key	Type	Description
seconds	number	seconds value
minutes	number	minutes value
hours	number	hours value
ampm	string	am/pm value if 12-hour format is used

---

Deprecation Warning:

Starting from v1.1.0 and above default export useTimer is deprecated, your old code will still work but it is better to start using named exports { useTimer, useStopwatch, useTime }