chronos

A JavaScript timer with simple and convenient API

Installation

Library can be installed via Bower package manager:

bower i chronosjs

An npm package also available:

$ npm install chronos-js

Or you can clone a git repo:

git clone https://github.com/happyCoda/chronos.git

Getting started

Just as simple as is.

var chr = new Chronos();

chr.start({
  direction: 'forward',
  callback: function (chr) {
    console.log(chr.composeString());
  }
});

Usage

Chronos.js is written as an AMD module, so it's intended to use with loaders like Require.js, Almond, etc. However, library can be used directly in browser, since it exposes global wrapper – ChronosWrapper.

API

start

Library entry point. Here all the gears and sprocket starts running.

chr.start({
  duration: 10000,
  callback: function (chrInst) {
    console.log(chrInst.composedToArray(chrInst.composeString())[2] + ' seconds left before explosion!');
  }
});

Start method expects to get an Object as an argument. This object can must have some of these configuration properties – direction, callback, duration and timeString. The first one, direction decides whether Chronos will act like a regular clock, or like a countdown timer. If direction is omitted, then Chronos will work like a timer. The callback option specifies a function callback which will be invoked every second with Chronos instance passed as an argument. duration represents time in milliseconds for a timer set up. If you have your setup time represented by a unix timestamp, you can pass this time as timeString property instead of duration.

stop

Chronos last stop.

chr.stop();

This method does exactly as it says. If you need to stop Chronos for time counting, just call stop.

composeString

Assembles current time value into a string.

Chronos.composeString();

composedToArray

Converts composed string into a usable array of time units (hours, mins, secs).

Chronos.composedToArray(composedString);

Examples

Create timer and write time to the page

In this example, we start Chronos with forward option and update changed time every second:

var clockDisplay = document.querySelector('.clock-display');

Chronos.start({
  direction: 'forward',
  callback: function (chr) {
    clockDisplay.textContent = chr.composeString();
  }
});

Counting time backwards

Creating a reverse timer:

var $timeLeft = $('.time-left'),
timeString = new Date(Date.now() + 60 * 60 * 1000);

Chronos.start({
  direction: 'backward',
  timeString: timeString
  callback: function (chr) {
    timeLeft.text(chr.composeString());
  }
});

Release History

• 2016-02-06   v0.5.4   Switched from singleton to constructor. Now multiple Chronos instances allowed.
• 2016-02-06   v0.4.4   Added support for timer duration in milliseconds.
• 2016-02-06   v0.4.3   AMD support refactor.
• 2016-02-05   v0.4.2   Case when backwards time is past fix.
• 2016-02-05   v0.4.1   Chronos time runner added.
• 2016-02-04   v0.3.0   Forward counting logic added.
• 2016-02-04   v0.2.3   Docs and bower integration.
• 2016-02-04   v0.2.2   adjustUnits method bug fixed.
• 2016-02-04   v0.2.1   Code refactor.
• 2016-02-04   v0.2.0   composedToArray method added & copyrights.
• 2016-02-04   v0.1.0   First official release. Tests and main logic.