Magento 1.9 – Get Last 3 Added Products from Cart

The call to

Mage::getSingleton('checkout/session')->getLastAddedProductId(true);

... is actually clearing the session variable after it is read. Magento uses magic methods extensively. In this case you are using the __call() magic method which in turn uses the getData() method. In Mage_Core_Model_Session_Abstract_Varien you will see that they override the default behaviour of getData() to expect the second parameter to be a boolean (The first parameter to getData() is the key name for the value you are looking for). That boolean is a flag telling the session to clear the variable after reading.

You could always listen for the checkout_cart_product_add_after event and add the item to your own variable in the session. That event is actually fired on the line before setLastAddedProductId() is called.

Refered links:

• https://stackoverflow.com/questions/7208650/get-id-of-the-last-product-added-to-the-cart-in-magento
• http://www.codexpedia.com/magento/magento-get-the-last-added-product-id-and-cart-items/

Edit 1:

You're almost there - try this code:

$collection = Mage::getSingelton('checkout/session')->getQuote()->getItemsCollection();

$collection->getSelect()->order('created_at DESC');

$latestItem = $collection->getFirstItem();

Note that when you get the latest quote item, you're not actually obtaining the product. To get the actual product, you would need to add this line:

$product = $latestItem->getProduct();

Edit 2:

Use this below code

Code to get the the full product information (where 3 is the configurable product Id)

$product = Mage::getModel('catalog/product')->load(3); 

$childProducts = Mage::getModel('catalog/product_type_configurable')
                ->getUsedProducts(null,$product);

foreach($childProducts as $child) {
    print_r($child->getName());  // You can use any of the magic get functions on this object to get the value
}

Edit 3:

You can also get by sku

$associated_products = $_product->loadByAttribute('sku', $_product->getSku())->getTypeInstance()->getUsedProducts();

foreach ($associated_products as $assoc) 
{
    $assocProduct   = Mage::getModel('catalog/product')->load($assoc->getId());
}

You can use checkout_cart_product_add_after event to allow or disallow products being added ...

app/code/local/My/Module/etc/config.xml

<?xml version="1.0" encoding="UTF-8"?>
<config>
    <modules>
        <My_Module>
            <version>0.0.1</version>
        </My_Module>
    </modules>
    <global>
        <models>
            <my_module>
                <class>My_Module_Model</class>
            </my_module>
        </models>
        <events>
            <checkout_cart_product_add_after>
                <observers>
                    <test>
                        <class>my_module/observer</class>
                        <method>disallowProductAddToCart</method>
                    </test>
                </observers>
            </checkout_cart_product_add_after>
        </events>
        <!-- make custom attrribute available in quote item product -->
        <sales>
            <quote>
                <item>
                    <product_attributes>
                        <preorder />
                    </product_attributes>
                </item>
            </quote>
        </sales>
    </global>
</config>

app/code/local/My/Module/Model/Observer.php

class My_Module_Model_Observer extends Mage_Core_Model_Observer
{
    public function disallowProductAddToCart(Varien_Event_Observer $observer)
    {
        $quote = $observer->getQuoteItem();
        $cartItems = $quote->getQuote()->getAllItems();

        if (count($cartItems) > 1) {
            $product = $observer->getProduct();
            $isPreorder = $product->getPreorder();

            if ($isPreorder) {
                $quote->getQuote()->removeItem($quote->getId());
                Mage::throwException(
                    Mage::helper('sales')->__('Can not add pre-order product to existing cart.')
                );
            }

            foreach ($cartItems as $item) {
                if (!$isPreorder && $item->getProduct()->getPreorder()) {
                    $quote->getQuote()->removeItem($quote->getId());
                    Mage::throwException(
                        Mage::helper('sales')->__('Cart already contains an pre-ordered product.')
                    );
                    break;
                }
            }
        }
    }
}

Edit: allow multiple "pre-order" products in cart

public function disallowProductAddToCart(Varien_Event_Observer $observer)
{
    $quote = $observer->getQuoteItem();
    $cartItems = $quote->getQuote()->getAllItems();

    if (count($cartItems) > 1) {
        $product = $observer->getProduct();
        $isPreorder = $product->getPreorder();

        foreach ($cartItems as $item) {
            if ($isPreorder != $item->getProduct()->getPreorder()) {
                $quote->getQuote()->removeItem($quote->getId());
                $message = $isPreorder ? 'Can not add pre-order product to existing cart.' : 'Cart already contains pre-ordered products.';
                Mage::throwException(
                    Mage::helper('sales')->__($message)
                );
                break;
            }
        }
    }
}

^{If your are curious why using checkout_cart_product_add_after and remove item from cart later $quote->getQuote()->removeItem($quote->getId()) ... it is just because there is no checkout_cart_product_add_before event dispatched in Mage_Checkout_Model_Cart::addProduct() :(}