Refresh header.phtml on click on add to cart button

Question

I am making a Free Shipping top bar, i have added code in header.phtml which is located in app/design/frontend/mytheme/mytheme05/template/page/html/header.phtml

My Code is :

<div id= "um" class="container" style="text-align: center; font-weight: bold; ">
<?php

$grand= $this->helper('checkout')->formatPrice(Mage::getSingleton('checkout/cart')->getQuote()->getGrandTotal()); 

$count = (int) filter_var($grand, FILTER_SANITIZE_NUMBER_INT);

$umer= 1500;
$total= $umer-$count;
if ($count < $umer)
{
    echo "Free Shipping on $total";
}

else 
    echo "Free Shipping Enjoy"; 
//var_dump($count)

?>

I want to refresh this div when Add to cart Button is press.

The code is located in :

app/design/frontend/mytheme/mytheme05/template/magiccart/magicproduct/product/grid.phtml

Code is here`

<div class="actions-cart">
<?php if(in_array("cart", $actions)):?>
    <?php if($_product->isSaleable()): ?>
        <button type="button" title="<?php echo $this->__('Add to cart') ?>" class="button btn-cart" onclick="setLocation('<?php echo $this->getAddToCartUrl($_product) ?>')"><span><span><?php echo $this->__('Add to Umer') ?></span></span></button>
    <?php else: ?>
        <p class="availability out-of-stock"><span><?php echo $this->__('Out of stock') ?></span></p>
    <?php endif; ?>
<?php endif; ?>

I want to refresh that div on onclick Button.

How I can do this ?

Answer 1

If you want to do this on reload the page, you have to add location.reload(); on onclick add to cart button, But i confirm that the best way is to do it with AJAX

For the product page for exemple:

app/design/frontend/{package}/{theme}/template/catalog/product/view/addtocart.phtml

<button type="button" title="<?php echo $buttonTitle ?>" id="product-addtocart-button" class="btn-cart btn btn-primary btn-sm" onclick="productAddToCartForm.submit(this); location.reload();"><?php echo $buttonTitle ?></button>

With Ajax :

function reload(url){
       $.get(url, function(data){      // $.get will get the content of the page defined in url and will return it in **data** variable 
            $('#row').append(data);
       }
    }

$('.button.btn-cart').click(function(e){ 
        e.preventDefault();
        var url = 'http://example.com/somepage.html';
        reload(url);  // this calls the reload function
});

Reference

Or you can do some load() function something like :

$("#myDiv").load(location.href+" #myDiv>*","");

Reference