Spining loader ajax

spining.js

function spining_calculator(target_div) {
    if (target_div == ''){
        var indicator = '<table id="indicator" style="width:100%;height:100%;" class="ajax_loading indicator_small"><tr><th style="text-align:center"><img src="/images/indicator-small.gif" /></th></tr></table>';
        $('body').prepend(indicator);
    } else {
        var width = $(target_div).width();
        var height = $(target_div).height();
        var indicator = '<table id="indicator" style="width:'+width+'px; height:'+height+'px;" class="ajax_loading indicator_small"><tr><th style="text-align:center"><img src="/images/indicator-small.gif" /></th></tr></table>';
        $(target_div).prepend(indicator);
    }
}
   $('#product_list .caption .added_to_cart').click(function() {
      spining_calculator($('#product_list'));
      var price_id, product_id, quantity;
      quantity = $(this).prev().val();
      product_id = $(this).attr('data-product-id');
      price_id = $(this).attr('data-price-id');
      $.ajax({
        type: 'POST',
        url: '/order_items',
        data: {
          quantity: quantity,
          product_id: product_id,
          price_id: price_id
        },
        success: function() {
          alert('Add to cart');
        },
        error: function() {
          alert('Try again');
        },
        complete: function() {
          $('#indicator').remove();
        }
      });
    });