How to get the custom attribute values in my catalog category list block

Question

I have added a custom attribute to my category. On category product listing page i want to retrieve the values of that custom attribute. When i got Mage/Catalog/Block/Product/List.php i can find this protected function _getProductCollection() function. Is this function that is getting the collection from the db? If yes how to get my custom attribute values in that method?

Or else which is the method that is responsible for getting collection from db and how to get the attribute value in that method?

EDIT: The purpose is to add some more skus to that collection based on the custom attribute value

Answer 1

Product Attribute

Just add it to this xpath:

/config/frontend/product/collection/attributes

You can find an example here:

/app/code/core/Mage/Catalog/etc/config.xml:718

Category Attribute

Just add it to this xpath:

/config/frontend/category/collection/attributes

You can find an example here:

/app/code/core/Mage/Catalog/etc/config.xml:742

Answer 2

You can make an event observer for catalog_block_product_list_collection_prepare.

In config.xml:

<global>
    <events>
        <catalog_block_product_list_collection_prepare>
            <observers>
                <add_custom_products>
                    <type>model</type>
                    <class>my_module/observer</class>
                    <method>productListCollectionAddCustomProducts</method>
                </add_custom_products>
            </observers>
        </catalog_block_product_list_collection_prepare>
    </events>
</global>

In MyModule/Model/Observer.php:

public function productListCollectionAddCustomProducts(Varien_Event_Observer $observer)
{
    /* @var $collection Mage_Catalog_Model_Resource_Product_Collection */
    $collection = $observer->getCollection();
    $filters = $collection->getLimitationFilters();
    if (!isset($filters['category_id']) || empty($filters['category_id']) || !is_string($filters['category_id'])) {
        return;
    }

    $categoryId = $filters['category_id'];
    $category = Mage::getModel('catalog/category')->load($categoryId);
    $myCustomParam = $category->getMyCustomParam();

    if ($myCustomParam == "something") {
        // ...
        // $collection->addItem($product);
    }
}

Answer 3

You can use simple way, without using object manager

<?php 
    $catalogHelperData = $this->helper('Magento\Catalog\Helper\Data');
    $categoryObject = $catalogHelperData->getCategory();
    $categoryId = $categoryObject->getId();
    $categoryName = $categoryObject->getName();
?>