Change by Observer Product Weight

Question

Im changing by checkout_cart_product_add_after the product Price and also want to change the Product weight.

here is the code: Magento 1.9.3

 public function checkoutCartProductAddAfter(Varien_Event_Observer $observer){
....

  // Get the quote item
  $item = $observer->getEvent()->getQuoteItem();

  // Ensure we have the parent item, if it has one
  $item = ( $item->getParentItem() ? $item->getParentItem() : $item );
  // Enable super mode on the product.
  $item->getProduct()->setIsSuperMode(true)

  $weight = /.some calculation based on custom configuration../
  $item->setWeight($weight); // not working
...
}

so the weight is still overwritten by

app/code/core/Mage/Sales/Model/Quote/item.php

 //line # 390
...
->setWeight($this->getProduct()->getWeight())
...

Have you any solution about this. Without changing the item.php file.

Thank you

Usman

My IDEA

So my Idea is to set here a custom Attribute like:

public function checkoutCartProductAddAfter(Varien_Event_Observer $observer){
....

  // Get the quote item
  $item = $observer->getEvent()->getQuoteItem();

  // Ensure we have the parent item, if it has one
  $item = ( $item->getParentItem() ? $item->getParentItem() : $item );
  // Enable super mode on the product.
  $item->getProduct()->setIsSuperMode(true)

  $weight = /.some calculation based on custom configuration../
  $item->setWeight($weight); // not working

  $item->setCustomWeight($weight); // here we set a custom attribute custom_weight and store the calculated weight
...
} 

and then set a second observer sales_quote_item_set_product

public function salesQuoteItemSetProduct(Varien_Event_Observer $observer){
    $_event     = $observer->getEvent();
    $_quoteItem = $_event->getQuoteItem();
    $_product   = $_quoteItem->getProduct();

    if ($weight = $_product->getData('custom_weight'))
        $_quoteItem->setWeight($weight);// set the new weight
}

but its still not working, because the Value of the Custom Attribute

custom_weight

is empty.

Answer 1

try:

after your code

$item->setWeight($weight);

add

$item->getProduct()->setWeight($weight);