Hi there,
First you have to load the categories because they are not present in this form. Just add this code:
foreach($this->order->products as $k => $product){
$ids[]=$product->product_id;
}
$db = JFactory::getDBO();
$query='SELECT * FROM '.hikashop_table('product_category').' as pc LEFT JOIN '.hikashop_table('category').' as c ON c.category_id=pc.category_id WHERE product_id IN ('.implode(',',$ids).')';
$db->setQuery($query);
$categories = $db->loadObjectList('product_id');
before this line:
foreach($this->order->products as $k => $product) {
Then add these lines:
<td class="hikashop_order_item_category_value"><?php echo $categories[$product->product_id]->category_name;?></td>
before:
<td class="hikashop_order_item_edit_value" style="text-align:center">
And
<th class="hikashop_order_item_category_title title titletoggle"><?php echo JText::_('CATEGORY'); ?></th>
before:
<th colspan="2" class="hikashop_order_item_remove_title title"><?php echo JText::_('ACTIONS'); ?></th>