That worked! Thank you! In case anyone wants to do this, I added this code to the product / cart.php view:
<?php
$cartQty=0;
foreach($this->rows as $i => $row){
$cartQty+=$row->cart_product_quantity;
}
if($cartQty == 0){
$config =& hikashop_config();
$continueShopping = $config->get('continue_shopping', '');
if(!empty($continueShopping)) {
global $Itemid;
$url_itemid='';
if(!empty($Itemid)){
$url_itemid='&Itemid='.$Itemid;
}
if(strpos($continueShopping,'Itemid') === false) {
if(strpos($continueShopping,'index.php?') !== false) {
$continueShopping .= $url_itemid;
}
}
if(!preg_match('#^https?://#',$continueShopping)) $continueShopping = JURI::base().ltrim($continueShopping,'/');
echo $this->cart->displayButton(JText::_('CONTINUE_SHOPPING'),'continue_shopping',$this->params,JRoute::_($continueShopping),'window.location=\''.JRoute::_($continueShopping).'\';return false;','id="hikashop_checkout_shopping_button"');
}
}
?>
Just before the final piece of code:
</div>
<div class="clear_both"></div>
<?php } ?>
<?php
if(JRequest::getWord('tmpl','')=='component'){
if(!headers_sent()){
header('Content-Type: text/css; charset=utf-8');
}
exit;
}