Great question — answering as the UphillTech team:
The key here is the line: <a class="btn btn-block hikabtn hikacart tglproduct_addtocart" href="index.php/component/hikashop/product/updatecart/add-1/cid-<?php echo (isset($product['characteristic'][0]['pid']) ? $product['characteristic'][0]['pid'] : $product['product_id']); ?>/quantity-1"><?php echo JText::_('MOD_HIKASHOP_TGLPRODUCTS_ADD_TO_CART'); ?></a> You have only implemented the fallback mechanism of the HikaShop add to cart, which is the direct add to cart link. In that case, the javascript of the add to cart system of HikaShop is not used and thus there is no dynamic refresh on the current page. If you want to use the javascript add to cart system to be able to add to the cart...
Full answer by Nico Isamu: https://stackoverflow.stackexchange.com/a/49610293 (CC BY-SA 4.0).
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