Timer JS

A simple event based timer.

Installation

npm install @ichabodcole/timer
yarn add @ichabodcole/timer

Basic Usage

import {
  Timer,
  TimerEvent, { type: TimerEventType, data?: TimerTickData }
  TimerEventTypes,
  TimerStates
} from '@ichabodcole/timer'

const duration = 5000 // A 5 second timer
const updateInterval = 100 // default is 50

var timer = new Timer(duration, updateInterval);

timer.on(TimerEvent.TICK, (e) => {
    console.log(
        e.type, // TICK
        e.data.duration, // The timer duration
        e.data.timeElapsed, // The amount of time that has elapsed
        e.data.progress // The timer progress as a value from 0..1
    );
});

timer.on(TimerEvent.COMPLETE, e => {
    console.log('YAY!', e.type)
});

// When the timer completes the COMPLETE, STOP, and RESET events 
// will be emitted automatically in that order.

// Events include START, STOP, TICK, RESET, COMPLETE

// Start the timer ticking
timer.start(); // Also timer.on(TimerEvent.START, ...

// The timer can be stopped at any point, which will freeze
// the current time values
// Calling start again will continue from the point
// the timer was stopped
timer.stop(); // Also timer.on(TimerEvent.STOP, ...

// Reset the timer to start from the beginning, this will happen on completion as well
timer.reset(); // Also timer.on(TimerEvent.RESET, ...
timer.start();

// The time duration and progression values
// can be updated while the timer is running
// and the timer will adjust accordingly
timer.duration = 7000
timer.timeElapsed = 3500
timer.progress = 0.5