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)

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Setup

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

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useTimer - Demo

Example

1import React from 'react';
2import { useTimer } from 'react-timer-hook';
3
4function MyTimer({ expiryTimestamp }) {
5  const {
6    totalSeconds,
7    milliseconds,
8    seconds,
9    minutes,
10    hours,
11    days,
12    isRunning,
13    start,
14    pause,
15    resume,
16    restart,
17  } = useTimer({ expiryTimestamp, onExpire: () => console.warn('onExpire called'), interval: 20 });
18
19
20  return (
21    <div style={{textAlign: 'center'}}>
22      <h1>react-timer-hook </h1>
23      <p>Timer Demo</p>
24      <div style={{fontSize: '100px'}}>
25        <span>{days}</span>:<span>{hours}</span>:<span>{minutes}</span>:<span>{seconds}</span>:<span>{milliseconds}</span>
26      </div>
27      <p>{isRunning ? 'Running' : 'Not running'}</p>
28      <button onClick={start}>Start</button>
29      <button onClick={pause}>Pause</button>
30      <button onClick={resume}>Resume</button>
31      <button onClick={() => {
32        // Restarts to 5 minutes timer
33        const time = new Date();
34        time.setSeconds(time.getSeconds() + 300);
35        restart(time)
36      }}>Restart</button>
37    </div>
38  );
39}
40
41export default function App() {
42  const time = new Date();
43  time.setSeconds(time.getSeconds() + 600); // 10 minutes timer
44  return (
45    <div>
46      <MyTimer expiryTimestamp={time} />
47    </div>
48  );
49}

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
interval	number	No	value to change the interval of the timer, by default it is set to 1000ms. Note: this value will not affect the timer, it will just define the frequency used to calculate the current timer values. For example, if you have a use case where milliseconds are used, you need to use a smaller value for the interval, for example, 20ms or 100ms based on your needs.
onExpire	Function	No	callback function to be executed once countdown timer is expired

Values

key	Type	Description
milliseconds	number	milliseconds value, to get accurate ms values you need to set interval to a smaller value example: 20ms
seconds	number	seconds value
minutes	number	minutes value
hours	number	hours value
days	number	days value
totalSeconds	number	total number of seconds left in timer NOT converted to minutes, hours or days
totalMilliseconds	number	total number of milliseconds left in timer NOT converted to minutes, hours or days
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

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useStopwatch - Demo

Example

1import React from 'react';
2import { useStopwatch } from 'react-timer-hook';
3
4function MyStopwatch() {
5  const {
6    totalSeconds,
7    milliseconds,
8    seconds,
9    minutes,
10    hours,
11    days,
12    isRunning,
13    start,
14    pause,
15    reset,
16  } = useStopwatch({ autoStart: true, interval: 20 });
17
18
19  return (
20    <div style={{textAlign: 'center'}}>
21      <h1>react-timer-hook</h1>
22      <p>Stopwatch Demo</p>
23      <div style={{fontSize: '100px'}}>
24        <span>{days}</span>:<span>{hours}</span>:<span>{minutes}</span>:<span>{seconds}</span>:<span>{milliseconds}</span>
25      </div>
26      <p>{isRunning ? 'Running' : 'Not running'}</p>
27      <button onClick={start}>Start</button>
28      <button onClick={pause}>Pause</button>
29      <button onClick={reset}>Reset</button>
30    </div>
31  );
32}
33
34export default function App() {
35  return (
36    <div>
37      <MyStopwatch />
38    </div>
39  );
40}

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
interval	number	No	value to change the interval of the stopwatch, by default it is set to 1000ms. Note: this value will not affect the stopwatch, it will just define the frequency used to calculate the current timer values. For example, if you have a use case where milliseconds are used, you need to use a smaller value for the interval, for example, 20ms or 100ms based on your needs.

Values

key	Type	Description
milliseconds	number	milliseconds value, to get accurate ms values you need to set interval to a smaller value example: 20ms
seconds	number	seconds value
minutes	number	minutes value
hours	number	hours value
days	number	days value
totalSeconds	number	total number of seconds in stopwatch NOT converted to minutes, hours or days
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

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useTime - Demo

Example

1import React from 'react';
2import { useTime } from 'react-timer-hook';
3
4function MyTime() {
5  const {
6    milliseconds,
7    seconds,
8    minutes,
9    hours,
10    ampm,
11  } = useTime({ format: '12-hour', interval: 20 });
12
13  return (
14    <div style={{textAlign: 'center'}}>
15      <h1>react-timer-hook </h1>
16      <p>Current Time Demo</p>
17      <div style={{fontSize: '100px'}}>
18        <span>{hours}</span>:<span>{minutes}</span>:<span>{seconds}</span><span>{milliseconds}</span><span>{ampm}</span>
19      </div>
20    </div>
21  );
22}
23
24export default function App() {
25  return (
26    <div>
27      <MyTime />
28    </div>
29  );
30}

Settings

key	Type	Required	Description
format	string	No	if set to 12-hour time will be formatted with am/pm
interval	number	No	value to change the interval of the time, by default it is set to 1000ms. Note: this value will not affect the thime, it will just define the frequency used to calculate the current time values. For example, if you have a use case where milliseconds are used, you need to use a smaller value for the interval, for example, 20ms or 100ms based on your needs.

Values

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

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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 }