How to show a different product variation other than the default one on page load ( ajax trigger )

Question

I have a node display for more than one product variation. Normally the user has to select one of the variation options by selecting them from the drop-down list which rebuilds the node display via AJAX.
Now say for instance that I want to link one of the product variations from else where. If I simply link www.example.com/node/10 the default product variation will be displayed which might not be the one I would like to present to the user.

So I probably have to send a query parameter in the URL, for example www.example.com/node/10?product_id=15, and trigger the AJAX event programmatically in my custom module.

Answer 1

Please see Implement unique URLs for particular products on product displays. It is an open feature request for Commerce, and it also links to a working sandbox with the implementation: http://drupal.org/sandbox/maciej.zgadzaj/1845182

Answer 2

Sure here you go, you'd have to modify for you own implementation.

/**
 * Implements hook_commerce_product_reference_default_delta_alter().
 */
function location_variant_flag_commerce_product_reference_default_delta_alter(&$delta, $products){
    $lang = LANGUAGE_NONE;

    //load the node
    $node = node_load(arg(1));
    //only execute if the hide location variant field is set to 1
    if(count($node->hide_location_variant) > 0 && $node->hide_location_variant[$lang][0]['value'] == 1){
        //get the default product based on the users location
        $default_product = location_variant_flag_get_default_product_for_user_location($products);

        if($default_product){
            //DC doesn't always return the delta consistently, sometimes it is the product id and
            //sometimes it is the array key so check if array key 0 exists, if so return the array key
            //otherwise return the product ID
            if(isset($products[0])){
                foreach($products as $key=>$product){
                    if($product->product_id == $default_product->product_id){
                        $delta = $key;
                        break;
                    }
                }
            }
            else{
                $delta = $default_product->product_id;
            }
        }
    }
}

Answer 3

<?php
/**
 * Implementation of hook_form_alter()
 */
 function MYMODULE_form_alter(&$form, $form_state, $form_id) {
   if (strpos($form_id,'commerce_cart_add_to_cart_form_') !== FALSE) {
    $product_id = $form['product_id']['#default_value'];

    foreach(drupal_get_query_parameters() as $paramenter => $argument) {
      if ($paramenter == 'product_id') {
        $product_id = $argument;
      }
    }

    $form['product_id']['#default_value'] = $product_id;

    if (!isset($form_state['triggering_element'])) {
      $form['product_id']['#ajax']['event'] = 'MYMODULE_commerce_variation_trigger';
      drupal_add_js(drupal_get_path('module', 'MYMODULE') . '/MYMODULE.js',  'file');
    }
  }
}
?>

MYMODULE.js
(function ($) {
  $(document).ready(function() {
    $('#edit-product-id').trigger('MYMODULE_commerce_variation_trigger');
  });
} (jQuery));

Answer 4

You can quite easily do this in a custom module using hook_commerce_product_reference_default_delta_alter()

Answer 5

Just because I've come across this twice, if you have a custom module for your custom functionality here is a quick and easy example of sending in a product id or sku as a query parameter using hook_commerce_product_reference_default_delta_alter:

function myModule_commerce_product_reference_default_delta_alter(&$delta, $products){
    if(isset($_GET['pid']) || isset($_GET['sku'])){

        //if a "pid" or "sku" parameter exists loop through the products that are attached to the node
        foreach($products as $key=>$product){

            //if the product id or sku matches the current productm set the delta to the key
            if($product->product_id==$_GET['pid'] || $product->sku==$_GET['sku']) $delta=$key;
        }
    }
}