javascript - Modify countdown script to allow for multiple countdowns per page

Question

I am utilizing the following script from CodePen

// Create Countdown
var Countdown = {

    // Backbone-like structure
    $el: $('.countdown'),

    // Params
    countdown_interval: null,
    total_seconds     : 0,

    // Initialize the countdown  
    init: function() {

    // DOM
        this.$ = {
        hours  : this.$el.find('.bloc-time.hours .figure'),
        minutes: this.$el.find('.bloc-time.min .figure'),
        seconds: this.$el.find('.bloc-time.sec .figure')
    };

    // Init countdown values
    this.values = {
            hours  : this.$.hours.parent().attr('data-init-value'),
        minutes: this.$.minutes.parent().attr('data-init-value'),
        seconds: this.$.seconds.parent().attr('data-init-value'),
    };

    // Initialize total seconds
    this.total_seconds = this.values.hours * 60 * 60 + (this.values.minutes * 60) + this.values.seconds;

    // Animate countdown to the end 
    this.count();    
    },

    count: function() {

    var that    = this,
        $hour_1 = this.$.hours.eq(0),
        $hour_2 = this.$.hours.eq(1),
        $min_1  = this.$.minutes.eq(0),
        $min_2  = this.$.minutes.eq(1),
        $sec_1  = this.$.seconds.eq(0),
        $sec_2  = this.$.seconds.eq(1);

        this.countdown_interval = setInterval(function() {

        if(that.total_seconds > 0) {

            --that.values.seconds;              

            if(that.values.minutes >= 0 && that.values.seconds < 0) {

                that.values.seconds = 59;
                --that.values.minutes;
            }

            if(that.values.hours >= 0 && that.values.minutes < 0) {

                that.values.minutes = 59;
                --that.values.hours;
            }

            // Update DOM values
            // Hours
            that.checkHour(that.values.hours, $hour_1, $hour_2);

            // Minutes
            that.checkHour(that.values.minutes, $min_1, $min_2);

            // Seconds
            that.checkHour(that.values.seconds, $sec_1, $sec_2);

            --that.total_seconds;
        }
        else {
            clearInterval(that.countdown_interval);
        }
    }, 1000);    
    },

    animateFigure: function($el, value) {

        var that         = this,
                $top         = $el.find('.top'),
            $bottom      = $el.find('.bottom'),
            $back_top    = $el.find('.top-back'),
            $back_bottom = $el.find('.bottom-back');

    // Before we begin, change the back value
    $back_top.find('span').html(value);

    // Also change the back bottom value
    $back_bottom.find('span').html(value);

    // Then animate
    TweenMax.to($top, 0.8, {
        rotationX           : '-180deg',
        transformPerspective: 300,
            ease                : Quart.easeOut,
        onComplete          : function() {

            $top.html(value);

            $bottom.html(value);

            TweenMax.set($top, { rotationX: 0 });
        }
    });

    TweenMax.to($back_top, 0.8, { 
        rotationX           : 0,
        transformPerspective: 300,
            ease                : Quart.easeOut, 
        clearProps          : 'all' 
    });    
    },

    checkHour: function(value, $el_1, $el_2) {

    var val_1       = value.toString().charAt(0),
        val_2       = value.toString().charAt(1),
        fig_1_value = $el_1.find('.top').html(),
        fig_2_value = $el_2.find('.top').html();

    if(value >= 10) {

        // Animate only if the figure has changed
        if(fig_1_value !== val_1) this.animateFigure($el_1, val_1);
        if(fig_2_value !== val_2) this.animateFigure($el_2, val_2);
    }
    else {

        // If we are under 10, replace first figure with 0
        if(fig_1_value !== '0') this.animateFigure($el_1, 0);
        if(fig_2_value !== val_1) this.animateFigure($el_2, val_1);
    }    
    }
};

// Let's go !
Countdown.init();

I have been trying to figure out for several hours how to modify it to support multiple countdown timers per page.

My approach so far was to try adding a numeric counter so that each "countdown" element gets a unique class, and then modifying the script to run on each element but this did not work and I don't think it will.

I'm not sure how else to approach it though so would appreciate some input.

Answer 1

You can create a new instance of this object with just a little bit of refactoring by converting it into a function.

For example, if you clone your <div class="countdown"/> HTML, and in JS you call:

new Countdown($($('.countdown')[0])).init();
new Countdown($($('.countdown')[1])).init();

Or, alternatively you could also initialize all .countdowns on page with:

$('.countdown').each((_, el) => (new Countdown($(el)).init()));

you will have two unique instances of the countdown.

// Create Countdown
function Countdown(node) {
  this.$el = node;
  this.countdown_interval = null;
  this.total_seconds = 0;
  this.init = function() {
    // DOM
    this.$ = {
      hours: this.$el.find('.bloc-time.hours .figure'),
      minutes: this.$el.find('.bloc-time.min .figure'),
      seconds: this.$el.find('.bloc-time.sec .figure')
    };

    // Init countdown values
    this.values = {
      hours: this.$.hours.parent().attr('data-init-value'),
      minutes: this.$.minutes.parent().attr('data-init-value'),
      seconds: this.$.seconds.parent().attr('data-init-value'),
    };

    // Initialize total seconds
    this.total_seconds = (this.values.hours * 60 * 60) +
      (this.values.minutes * 60) +
      this.values.seconds;
    // Animate countdown to the end 
    this.count();
  };
  this.count = function() {
    let that = this,
      $hour_1 = this.$.hours.eq(0),
      $hour_2 = this.$.hours.eq(1),
      $min_1 = this.$.minutes.eq(0),
      $min_2 = this.$.minutes.eq(1),
      $sec_1 = this.$.seconds.eq(0),
      $sec_2 = this.$.seconds.eq(1);

    this.countdown_interval = setInterval(function() {
      if (that.total_seconds > 0) {
        --that.values.seconds;
        if (that.values.minutes >= 0 && that.values.seconds < 0) {
          that.values.seconds = 59;
          --that.values.minutes;
        }

        if (that.values.hours >= 0 && that.values.minutes < 0) {
          that.values.minutes = 59;
          --that.values.hours;
        }

        // Update DOM values
        // Hours
        that.checkHour(that.values.hours, $hour_1, $hour_2);
        // Minutes
        that.checkHour(that.values.minutes, $min_1, $min_2);
        // Seconds
        that.checkHour(that.values.seconds, $sec_1, $sec_2);

        --that.total_seconds;
      } else {
        clearInterval(that.countdown_interval);
      }
    }, 1000);
  };
  this.animateFigure = function($el, value) {
    let that = this,
      $top = $el.find('.top'),
      $bottom = $el.find('.bottom'),
      $back_top = $el.find('.top-back'),
      $back_bottom = $el.find('.bottom-back');

    // Before we begin, change the back value
    $back_top.find('span').html(value);

    // Also change the back bottom value
    $back_bottom.find('span').html(value);

    // Then animate
    TweenMax.to($top, 0.8, {
      rotationX: '-180deg',
      transformPerspective: 300,
      ease: Quart.easeOut,
      onComplete: function() {
        $top.html(value);
        $bottom.html(value);
        TweenMax.set($top, {
          rotationX: 0
        });
      }
    });

    TweenMax.to($back_top, 0.8, {
      rotationX: 0,
      transformPerspective: 300,
      ease: Quart.easeOut,
      clearProps: 'all'
    });
  };
  this.checkHour = function(value, $el_1, $el_2) {
    let val_1 = value.toString().charAt(0),
      val_2 = value.toString().charAt(1),
      fig_1_value = $el_1.find('.top').html(),
      fig_2_value = $el_2.find('.top').html();

    if (value >= 10) {
      // Animate only if the figure has changed
      if (fig_1_value !== val_1) this.animateFigure($el_1, val_1);
      if (fig_2_value !== val_2) this.animateFigure($el_2, val_2);
    } else {
      // If we are under 10, replace first figure with 0
      if (fig_1_value !== '0') this.animateFigure($el_1, 0);
      if (fig_2_value !== val_1) this.animateFigure($el_2, val_1);
    }
  }
}

// Let's go !
new Countdown($($('.countdown')[0])).init();
new Countdown($($('.countdown')[1])).init();

// Alternatively you could also initialize all countdowns on page with:
// $('.countdown').each((i, el) => (new Countdown($(el)).init()));

body {
  background-color: #f2f1ed;
}

.wrap {
  position: absolute;
  bottom: 0;
  top: 0;
  left: 0;
  right: 0;
  margin: auto;
  height: 310px;
}

a {
  text-decoration: none;
  color: #1a1a1a;
}

h1 {
  margin-bottom: 60px;
  text-align: center;
  font: 300 2.25em "Lato";
  text-transform: uppercase;
}

h1 strong {
  font-weight: 400;
  color: #ea4c4c;
}

h2 {
  margin-bottom: 80px;
  text-align: center;
  font: 300 0.7em "Lato";
  text-transform: uppercase;
}

h2 strong {
  font-weight: 400;
}

.countdown {
  width: 720px;
  margin: 4px 0;
  display: inline-block;
}

.countdown .bloc-time {
  float: left;
  margin-right: 45px;
  text-align: center;
}

.countdown .bloc-time:last-child {
  margin-right: 0;
}

.countdown .count-title {
  display: block;
  margin-bottom: 15px;
  font: normal 0.94em "Lato";
  color: #1a1a1a;
  text-transform: uppercase;
}

.countdown .figure {
  position: relative;
  float: left;
  height: 110px;
  width: 100px;
  margin-right: 10px;
  background-color: #fff;
  border-radius: 8px;
  -moz-box-shadow: 0 3px 4px 0 rgba(0, 0, 0, 0.2), inset 2px 4px 0 0 rgba(255, 255, 255, 0.08);
  -webkit-box-shadow: 0 3px 4px 0 rgba(0, 0, 0, 0.2), inset 2px 4px 0 0 rgba(255, 255, 255, 0.08);
  box-shadow: 0 3px 4px 0 rgba(0, 0, 0, 0.2), inset 2px 4px 0 0 rgba(255, 255, 255, 0.08);
}

.countdown .figure:last-child {
  margin-right: 0;
}

.countdown .figure>span {
  position: absolute;
  left: 0;
  right: 0;
  margin: auto;
  font: normal 5.94em/107px "Lato";
  font-weight: 700;
  color: #de4848;
}

.countdown .figure .top:after,
.countdown .figure .bottom-back:after {
  content: "";
  position: absolute;
  z-index: -1;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 100%;
  border-bottom: 1px solid rgba(0, 0, 0, 0.1);
}

.countdown .figure .top {
  z-index: 3;
  background-color: #f7f7f7;
  transform-origin: 50% 100%;
  -webkit-transform-origin: 50% 100%;
  -moz-border-radius-topleft: 10px;
  -webkit-border-top-left-radius: 10px;
  border-top-left-radius: 10px;
  -moz-border-radius-topright: 10px;
  -webkit-border-top-right-radius: 10px;
  border-top-right-radius: 10px;
  -moz-transform: perspective(200px);
  -ms-transform: perspective(200px);
  -webkit-transform: perspective(200px);
  transform: perspective(200px);
}

.countdown .figure .bottom {
  z-index: 1;
}

.countdown .figure .bottom:before {
  content: "";
  position: absolute;
  display: block;
  top: 0;
  left: 0;
  width: 100%;
  height: 50%;
  background-color: rgba(0, 0, 0, 0.02);
}

.countdown .figure .bottom-back {
  z-index: 2;
  top: 0;
  height: 50%;
  overflow: hidden;
  background-color: #f7f7f7;
  -moz-border-radius-topleft: 10px;
  -webkit-border-top-left-radius: 10px;
  border-top-left-radius: 10px;
  -moz-border-radius-topright: 10px;
  -webkit-border-top-right-radius: 10px;
  border-top-right-radius: 10px;
}

.countdown .figure .bottom-back span {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  margin: auto;
}

.countdown .figure .top,
.countdown .figure .top-back {
  height: 50%;
  overflow: hidden;
  -moz-backface-visibility: hidden;
  -webkit-backface-visibility: hidden;
  backface-visibility: hidden;
}

.countdown .figure .top-back {
  z-index: 4;
  bottom: 0;
  background-color: #fff;
  -webkit-transform-origin: 50% 0;
  transform-origin: 50% 0;
  -moz-transform: perspective(200px) rotateX(180deg);
  -ms-transform: perspective(200px) rotateX(180deg);
  -webkit-transform: perspective(200px) rotateX(180deg);
  transform: perspective(200px) rotateX(180deg);
  -moz-border-radius-bottomleft: 10px;
  -webkit-border-bottom-left-radius: 10px;
  border-bottom-left-radius: 10px;
  -moz-border-radius-bottomright: 10px;
  -webkit-border-bottom-right-radius: 10px;
  border-bottom-right-radius: 10px;
}

.countdown .figure .top-back span {
  position: absolute;
  top: -100%;
  left: 0;
  right: 0;
  margin: auto;
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/gsap/latest/TweenMax.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<div class="wrap">
  <h1>Draft <strong>Countdown</strong></h1>

  <!-- Countdown #1 -->
  <div class="countdown">
    <div class="bloc-time hours" data-init-value="24">
      <span class="count-title">Hours</span>

      <div class="figure hours hours-1">
        <span class="top">2</span>
        <span class="top-back">
          <span>2</span>
        </span>
        <span class="bottom">2</span>
        <span class="bottom-back">
          <span>2</span>
        </span>
      </div>

      <div class="figure hours hours-2">
        <span class="top">4</span>
        <span class="top-back">
          <span>4</span>
        </span>
        <span class="bottom">4</span>
        <span class="bottom-back">
          <span>4</span>
        </span>
      </div>
    </div>

    <div class="bloc-time min" data-init-value="0">
      <span class="count-title">Minutes</span>

      <div class="figure min min-1">
        <span class="top">0</span>
        <span class="top-back">
          <span>0</span>
        </span>
        <span class="bottom">0</span>
        <span class="bottom-back">
          <span>0</span>
        </span>
      </div>

      <div class="figure min min-2">
        <span class="top">0</span>
        <span class="top-back">
          <span>0</span>
        </span>
        <span class="bottom">0</span>
        <span class="bottom-back">
          <span>0</span>
        </span>
      </div>
    </div>

    <div class="bloc-time sec" data-init-value="0">
      <span class="count-title">Seconds</span>

      <div class="figure sec sec-1">
        <span class="top">0</span>
        <span class="top-back">
          <span>0</span>
        </span>
        <span class="bottom">0</span>
        <span class="bottom-back">
          <span>0</span>
        </span>
      </div>

      <div class="figure sec sec-2">
        <span class="top">0</span>
        <span class="top-back">
          <span>0</span>
        </span>
        <span class="bottom">0</span>
        <span class="bottom-back">
          <span>0</span>
        </span>
      </div>
    </div>
  </div>

  <div class="countdown">
    <div class="bloc-time hours" data-init-value="4">
      <span class="count-title">Hours</span>

      &l