Magento resource model catalog product filter with attributes and category id

Question

I am trying to develop custom filter navigation. Below is the code for product collection by category id

$category = Mage::getModel ('catalog/category')->load($category_id);
    $products = Mage::getResourceModel('catalog/product_collection')
                  // ->addAttributeToSelect('*')
                  ->AddAttributeToSelect('name')
                  ->addAttributeToSelect('price')
                  ->addFinalPrice()
                  ->addAttributeToSelect('small_image')
                  ->addAttributeToSelect('image')
                  ->addAttributeToSelect('thumbnail')
                  ->addAttributeToSelect('short_description')
                  ->addUrlRewrite()
                  ->AddCategoryFilter($category);


    Mage::getSingleton('catalog/product_visibility')->addVisibleInCatalogFilterToCollection($products);

    //$products->addAttributeToFilter('color', array('eq' => '27')); /* here color attribute */

Product collection by category id is working as expected. But when i tried with single color attribute, it always returns an empty array. Same color 27 attribute gives one product as result when i check on default navigation.

What is the best way to achieve multiple attribute code filter with resource model catalog product collection?

Answer 1

Try this:

        $products = Mage::getModel('catalog/category')->load($category_id)->getProductCollection();
        $products
              ->addAttributeToSelect('name')
              ->addAttributeToSelect('price')
              ->addFinalPrice()
              ->addAttributeToSelect('small_image')
              ->addAttributeToSelect('image')
              ->addAttributeToSelect('thumbnail')
              ->addAttributeToSelect('short_description')
              ->addUrlRewrite()

              //select color too
              ->addAttributeToSelect('color')
              ->addAttributeToFilter(array(
                 array('attribute'=> 'color','eq' => '27')
                ))
              ;

Answer 2

have check if the attribute has been set to yes ( display in frontend ) into BO and try this :

$products->addAttributeToFilter('color', array('in' => array('the color ids you picked separated by a comma')))