如何按前端受欢迎程度对Magento产品进行分类？

Question

I have created a module to add a new option in 'sort by' dropdown box in the category page. the new option should show in each and every category page same as 'position' option which is already there. I want to add 'popularity' as an option. My Model class is executing and it's adding the option to the option array. But the block is not working. Please I need your help to find the issue in my code?

Here is the Block class

<?php
class Tal_Popularity_Block_Product_List_Toolbar extends Mage_Catalog_Block_Product_List_Toolbar
{
    public function setCollection($collection)
   {
       $this->_collection = $collection;
       $this->_collection->setCurPage($this->getCurrentPage());
       // we need to set pagination only if passed value integer and more that 0
       $limit = (int)$this->getLimit();
       if ($limit) {
           $this->_collection->setPageSize($limit);
       }
        if($this->getCurrentOrder() == 'popularity'){
           $this->_collection->sortByReview($this->getCurrentDirection());
       }
     else if ($this->getCurrentOrder()) {

           $this->_collection->setOrder($this->getCurrentOrder(), $this->getCurrentDirection());
    }

       return $this;
   }
}

following is my config.xml

<?xml version="1.0" ?>
 <config>
    <modules>
        <Tal_Popularity>
            <version>0.1.0</version>
        </Tal_Popularity>
    </modules>
    <frontend>
        <routers>
            <popularity>
                <use>standard</use>
                <args>
                    <module>Tal_Popularity</module>
                    <frontName>popularity</frontName>
                </args>
            </popularity>
        </routers>
    </frontend>
    <global>
    <models>
        <catalog>
            <rewrite>
                <config>Tal_Popularity_Model_Config</config>
            </rewrite>
        </catalog>
    </models>
     <blocks>
        <catalog>
            <rewrite>
                <catalog>Tal_Popularity_Block</catalog>
            </rewrite>
           </catalog>
        </blocks>
         <resources>
            <popularity_setup>
                <setup>
                    <module>Tal_Popularity</module>
                </setup>
                <connection>
                    <use>core_setup</use>
                </connection>
            </popularity_setup>
            <popularity_write>
                <connection>
                    <use>core_write</use>
                </connection>
            </popularity_write>
            <popularity_read>
                <connection>
                    <use>core_read</use>
                </connection>
            </popularity_read>
        </resources>
    </global>
</config>

Answer 1

I found the solution. The issue was in the config.xml

Previous code.

<blocks>
        <catalog>
            <rewrite>
                <catalog>Tal_Popularity_Block</catalog>
            </rewrite>
           </catalog>
        </blocks>

The above code should be like following.

 <blocks>
            <catalog>
                <rewrite>            <product_list_toolbar>Tal_Popularity_Block_Product_List_Toolbar</product_list_toolbar>
                </rewrite>
               </catalog>
            </blocks>