Magento - Stop child products showing in anchor category

Question

On an anchor category page I'm trying to only show the products directly contained within the category. I don't want to show the products of child categories, it's not appropriate in this case. I really do need to filter the products in my current category, so I need layered navigation, which necessitates an anchor category.

Initially I thought to filter the products in the view.phtml template, but that only filters the products in the view and is not a sensible answer. When I do this I end up with big gaps on my page where child products are present, but simply not displayed. And the product counts (eg. "1-12 of 117 products") are "incorrect".

From what I've read, this is going to require a core rewrite. Probably of an index process. I don't really know where to start with this rewrite, and I'm sure it's going to be rather involved.

Are any of my assumptions wrong? Have you already solved this problem?

Answer 1

Goto app/code/core/Mage/Catalog/Model/Resource/Product/Collection.php

copy to app/code/local/Mage/Catalog/Model/Resource/Product/Collection.php

find function addCategoryFilter( and here you you find code

 public function addCategoryFilter(Mage_Catalog_Model_Category $category)
    {
        $this->_productLimitationFilters['category_id'] = $category->getId();
/*    start to comment here     
if ($category->getIsAnchor()) {
            unset($this->_productLimitationFilters['category_is_anchor']);
        } else {
            $this->_productLimitationFilters['category_is_anchor'] = 1;
        }*/
/* new line */

     $this->_productLimitationFilters['category_is_anchor'] = 1;

        if ($this->getStoreId() == Mage_Catalog_Model_Abstract::DEFAULT_STORE_ID) {
            $this->_applyZeroStoreProductLimitations();
        } else {
            $this->_applyProductLimitations();
        }

        return $this;
    }

Answer 2

You don't need a single line of code if I have understood your condition correct. Magento provides the freedom to enter products in any category regardless of their hierarchy.

So consider the following scenario:

Category A->Category a

Then a product can be assigned to only category a and not to category A. This will work in harmony with the entire magento system including layered navigation and no of prouducts shown on page.