Hide other shipping methods when free shipping is enabled [duplicate]

Question

I'm trying to create a module that lets me disable other shipping modes when free shipping is available.

I understand how to create a module and such, I can understand php relatively well I'm just lost as to how to filter this in regard to magento. I'm aware that you someone overwrite some existing rules within the module I'm making.

If someone could guide me as to how I do this within the xml file and the functions I need to use I'd be very grateful.

I've taken some steps into creating one myself after bits of googling.

<?xml version="1.0"?>
    <config>
        <modules>
            <Shipping_Onepage_Method>
                <version>1.0.0</version>
            </Shipping_Onepage_Method>
        </modules>

                    <blocks>
                        <checkout>
                            <rewrite>
                                <shipping_onepage_model_method>Shipping_Onepage_Model_Method</onepage_shipping_model_method>
                            </rewrite>
                        </checkout>
                    </blocks>

    </config>

Then I've got located in /public_html/app/code/local/Markshust/Helloworld/model/available.php

I've got the following code which I'm led to believe will filter the shipping prices as I wish.

 <?Php
class Shipping_Onepage_Model_Method extends Mage_Checkout_Block_Onepage_Shipping_Method_Available
{
    public function getShippingRates()
    {
        $rates = parent::getShippingRates();
        if (array_key_exists('freeshipping', $rates)) {
            $rates = array('freeshipping' => $rates['freeshipping']);
        }

        return $rates;
    }
}

?> 

This doesn't seem to work, I've made amends on my xml file since made aware of the faults in the latest awnser.

Thanks

Answer 1

Config.xml code is wrong

   <?xml version="1.0"?>
    <config>
        <modules>
            <Shipping_Onepage>
                <version>1.0.0</version>
            </Shipping_Onepage>
        </modules>
<global>

                    <blocks>
            <shippingonepage>
            <class>Amit_RemoveShip_Model</class>
            </shippingonepage>

                        <checkout>
                            <rewrite>
                                <onepage_shipping_method_available>Shipping_Onepage_Block_Method</onepage_shipping_method_available>
                            </rewrite>
                        </checkout>
                    </blocks>
   <global>
    </config>

Method.php(Shipping>Onepag>Block>Method.php) code

   <?php
    class Shipping_Onepage_Block_Method extends Mage_Checkout_Block_Onepage_Shipping_Method_Available
{
    public function getShippingRates()
    {
        $rates = parent::getShippingRates();
        if (array_key_exists('freeshipping', $rates)) {
            $rates = array('freeshipping' => $rates['freeshipping']);
        }

        return $rates;
    }
}

Answer 2

Your rewrite directive is incorrect. Your directive says : rewrite the class located in 'markshust_helloworld', in the module 'checkout' with the class 'MagePsycho_Shipmentfilter_Block_Onepage_Shipping_Method_Available'

the correct rewrite format is:

<blocks>
   <module>
     <rewrite>
      <path_to_class>YOUR MODULE CLASS</path_to_class>
     </rewrite>
   </module>
</blocks>

so, if for instance you want to rewrite the core class 'Mage_Checkout_Block_Onepage_Shipping_Method' you'd rewrite it as such:

<blocks>
   <checkout>
     <rewrite>
       <onepage_shipping_method>YOUR MODULE CLASS</onepage_shipping_method>
     </rewrite>
   </checkout>
</blocks>

additionally, your <blocks> element is inside the <routers> element, which is incorrect. Blocks is not a property of the routers configuration.

Personally, I think creating a module to do this is overkill. You can use a bit of javascript (inserted to the checkout page via layout js directive in the checkout handles) to determine if freeshipping option is available, and if so set all the other shipping methods as hidden.

Off the op of my head something like this will iterate all the shipping methods, using jQuery

jQuery('#co-shipping-method-form input[type=radio]').each(function(){
            // test and do something with the shipping method
});

you can then also set the freeshipping option as checked at the same time.

Answer 3

first please rename your module to "Shipping_Method"

<modules>
    <Shipping_Method>
        <version>1.0.0</version>
    </Shipping_Method>
</modules>

Rename your Block file to: /app/code/local/Shipping/Method/Block/Shipping/Method.php

your rewrite configuration should be like:

<blocks>
    <checkout>
        <rewrite>
            <onepage_shipping_method_available>Shipping_Method_Block_Shipping_Method</onepage_shipping_method_available>
        </rewrite>
    </checkout>
</blocks>

in the Method.php:

<?php
class Shipping_Method_Block_Shipping_Method extends Mage_Checkout_Block_Onepage_Shipping_Method_Available
{
    public function getShippingRates()
    {
        $rates = parent::getShippingRates();
        if (array_key_exists('freeshipping', $rates)) {
            $rates = array('freeshipping' => $rates['freeshipping']);
        }

        return $rates;
    }
}

then it should work...