Shopify - Real time cart update

realTimeCartUpdate.liquid

{% for item in cart.items %}
  <div class="mbl-cart-container" id="DevLine-{{forloop.index}}">  
    <div class="mbl-quantity">
        <p><i class="fas fa-plus" data-line-id="{{ forloop.index }}"></i></p>
        <p class="dev-line-qty" id="Q-{{forloop.index}}">{{ item.quantity }}</p>
        <p><i class="fas fa-minus" data-line-id="{{ forloop.index }}"></i></p>
    </div>

      <div class="mbl-line-image">
        <a href="{{ item.url }}">
          <img src="{{ item | img_url: 'small' }}"  alt="{{ item.title | escape }}" />
        </a>
      </div>
      <!-- todo: Should this be a link to the product page? -->
      <div class="mbl-line-title">
        <h3><a class="name" href="{{ item.url }}">{{ item.title }}</a></h3>
        <p class="DevLinePrice">{{ item.line_price | money }}</p>
	 <a class="cart-removal" data-line-id="{{ forloop.index }}" href="/cart/change?line={{ forloop.index }}&quantity=0" rel="{{ item.id }}">Remove Item</a>
      </div>
  </div>
{% endfor %}
<script>
  $('.mbl-quantity .fas').on('click', function(){
  	console.log('clicked +');
  		var lineID = $(this).data('line-id');
    	var lineQty = $('#Q-'+lineID).text();
    	var newQty = parseInt(lineQty)+parseInt(1);
        if($(this).hasClass('fa-minus')){
			newQty = parseInt(lineQty)-parseInt(1);
        }
        if(newQty == 0){
            //do nothing
        }else{
    	  //update quantity value
    	  $('#Q-'+lineID).text(newQty);
          //update the cart
          jQuery.post('/cart/change.js', { line: lineID, quantity: newQty });
                       
            
          });
          
          setTimeout(function(){
          
			//update the cart price
             $.ajax({
                type: 'GET',
                url: '/cart.json',
                dataType: 'jsonp',
                success: function(datax) { 
                  var theLineId = parseInt(lineID)-parseInt(1);
                  var selectedItem = datax.items[theLineId];
                  var thisPrice = selectedItem.line_price;
                  thisPrice = Shopify.formatMoney(thisPrice);
                  $('#DevLine-'+lineID).find('.DevLinePrice').html(thisPrice);

                  //update subtotal
                  var cartTotalPrice = Shopify.formatMoney(datax.total_price);
                  $('.devSubtotal').html(cartTotalPrice);
                 }
              });           
          
          }, 1000);
        }
  });
</script>