How to add multi-select attribute in Admin product Grid view

Here I've shown a multi-select attribute named "brand".

>> In admin Grid.php find the method "_prepareColumns()" add the following code:

        $attribute = Mage::getModel('eav/config')->getAttribute('catalog_product', 'brand');        // attribute code here
        foreach ( $attribute->getSource()->getAllOptions(true, true) as $option)
        {
            if($option['value'] != '')
            $valArr[$option['value']] =  $option['label'];
        }
        // above code will use to show the dropdown
       
        $this->addColumn('brand',
            array(
                'header'=> Mage::helper('catalog')->__('Brands'),
                'width' => '60px',
                'index' => 'brand',
                'type'  => 'options',
                'options' => $valArr,
                'renderer'  => 'Mage_Adminhtml_Block_Catalog_Product_Renderer_Brands', // Will have to create the renderer.
                'filter_condition_callback' => array($this, '_filterBrandCondition')
        ));
       
        Then in this page you need to define the method "_filterBrandCondition" to filter with selected item.
       
        protected function _filterBrandCondition($collection, $column)
        {
            if (!$value = $column->getFilter()->getValue()) {
                return;
            }
            $this->getCollection()->addFieldToFilter('brand', array('finset' => $value));
        }
       
       
>> Now create the Brands.php file in code/local/Mage/Adminhtml/Block/Catalog/Product/Renderer directory and use the following code:

        class Mage_Adminhtml_Block_Catalog_Product_Renderer_Brands extends Mage_Adminhtml_Block_Widget_Grid_Column_Renderer_Abstract
        {
            public function render(Varien_Object $row)
            {
                $brands = explode(',',$row->getBrand());
                $html = "";
                if(count($brands)>0)
                {
                    $html ="<ul>";
                    foreach($brands as $value)
                    {
                        $_productModel = Mage::getModel('catalog/product');
                        $attribute = $_productModel->getResource()->getAttribute("brand");
                        if ($attribute ->usesSource()) {
                            $html .= "<li>".$attribute ->getSource()->getOptionText("$value")."</li>";
                        }
                    }
                    $html .= "</ul>";
                }
                return $html ;
            }
        }
       
 cheer :-)

Add extra cost to every shipping method in Magento

>>  I needed to add extra cost to every shipping method price. There would be any other better way to do it but I did the following :

         Open the Rate.php file within app/code/core/Mage/Sales/Model/Quote/Address directory. Find this method:
    public function importShippingRate(Mage_Shipping_Model_Rate_Result_Abstract $rate)
    {
        if ($rate instanceof Mage_Shipping_Model_Rate_Result_Error) {
            $this
                ->setCode($rate->getCarrier().'_error')
                ->setCarrier($rate->getCarrier())
                ->setCarrierTitle($rate->getCarrierTitle())
                ->setErrorMessage($rate->getErrorMessage())
            ;
        } elseif ($rate instanceof Mage_Shipping_Model_Rate_Result_Method) {
            $this
                ->setCode($rate->getCarrier().'_'.$rate->getMethod())
                ->setCarrier($rate->getCarrier())
                ->setCarrierTitle($rate->getCarrierTitle())
                ->setMethod($rate->getMethod())
                ->setMethodTitle($rate->getMethodTitle())
                ->setMethodDescription($rate->getMethodDescription())
                ->setPrice($rate->getPrice())
            ;
        }
        return $this;
    }

    Add extra 10 price with $rate->getPrice() like :  
                   ->setPrice($rate->getPrice()+10)


  Note: Editing the core file is not a good practice. If anyone find any other solution, please must share with me. :)

Import dump data to mysql through command promt

>> Mysql import from CSV :

      > mysqlimport --fields-terminated-by=, --fields-enclosed-by="\"" --lines-terminated-by="\r\n" DBNAME FILEPATH -u USERNAME -p --columns=code,city,state,county

How to get all subcategories of a category in Magento

 >> Suppose you need to get the list of all subcategory of "cat1" (id : 10)

    <?php
       $category = Mage::getModel('catalog/category')->load(10); // load the parent category
    ?>
    There are many way to do it. I'll show you the two :
   
    1. $subcatCollection = Mage::getModel('catalog/category')->getCollection()
                ->addAttributeToSelect('*')
                ->addAttributeToFilter('is_active','1')
                ->addAttributeToFilter('parent_id',array('eq' => 10));
               
       // This will return the subcategory collection.
               
   2. $subcategories = $category->getChildren();
   
       // This will return all subcategory id with comma separator like : 11,12,13

How to show review block on product page in Magento

>> To get the review block in product details page. You need to follow the two steps:

       1) Add this code to catalog.xml like:
            <catalog_product_view translate="label">
                <reference name="content">
                    <block type="catalog/product_view" name="product.info" template="catalog/product/view.phtml">
                       
                            <!--You need to copy below section -->
                        <block type="page/html_pager" name="product_review_list.toolbar"/>
                        <block type="core/template" name="product_review_list.count" template="review/product/view/count.phtml" />
                        <block type="review/product_view_list" name="product.detail.info.product_additional_data" as="product_review_data" template="review/product/view/list.phtml">
                            <block type="review/form" name="product.review.form" as="review_form">
                                <block type="page/html_wrapper" name="product.review.form.fields.before" as="form_fields_before" translate="label">
                                    <label>Review Form Fields Before</label>
                                    <action method="setMayBeInvisible"><value>1</value></action>
                                </block>
                            </block>
                        </block>
                            <!--        END            -->
                  
                   </block>
               </reference>
            </catalog_product_view>
           
       2) Now go to the view.phtml page. here you need to add this code:
      
               <?php echo $this->getChildHtml('product_review_data') ?>
           
            you are done> :)
           
           
>> To change the default number of reviews shown per page, follow this:

        By default it shows 10, 20, 50. Go to app/code/core/Mage/Page/Block/Html/Pager.php
        there you can find the line 
            <?php protected $_availableLimit = array(10=>10,20=>20,50=>50);  ?>
           
        change it as you want        
            <?php protected $_availableLimit = array(5=>5,10=>10,50=>50);  ?>
           
   Note*: You should do this step either by overriding the block OR copy the same file in the local directory like:  app/code/local/Mage/Page/Block/Html/Pager.php

Custom error/success message in Magento

>> A simple and most needed thing that we frequently use in Magento that how to add custom Error and Success message in Controller page.

You just need to call these methods:
$session = Mage::getSingleton('core/session');  
// You can specify the session with yours like:  
// Mage::getSingleton('customer/session'),
// Mage::getSingleton('checkout/session')

$session->addSuccess('your message here');
$session->addError('your message here');

Special character of Regular Expression

Regular Expression :

>> Meaning of Special character [](){}|?+-*^$\

    []    => Square brackets can be used to define a character group. [abc] The example finds one of the characters a, b or c.   

    -    => The hyphen can be used to define a range of characters. [a-f] The example finds one of the characters a, b, c, d, e or f. Also in this example, the regular expression only matches one character.

    ^    => With the meta character ^ at the beginning of a character group, the character group is negated. That means, the example will match any character but not an a. [^a]

           ^a If the meta character ^ is not included into a character group, it stands for the beginning of a string or a line. The example would match all lines or strings beginning with a.

    $    => a$ Like the meta character ^ stands for the beginning of a string or a line, the character $ stands for its end. The example would match all strings or lines ending with an a.
   
            ^abc$ Here the meta characters ^ and $ are used together. This example would match all strings or lines which are equal to "abc".
            Example 1: abc
            Example 2: abc abc