Magento 2: Why this event is not working for me? prepare_catalog_product_index_select

Question

Magento version: 2.0

events.xml

<event name="prepare_catalog_product_index_select">
        <observer name="list_product_observer" instance="Demo\Product\Observer\ListProductObserver" />
    </event>

ListProductObserver.php

class ListProductObserver implements ObserverInterface
{   
    public function execute(Observer $observer)
    {
        $data = array(
            'product' => $productId,
            'user'  => $userId,
            'value' => 333
        );
        $myfile = fopen("/file_path/ListProductObserver.txt", "w");
        fwrite($myfile, print_r($data, true));
        fclose($myfile);
    }
}

I create a function to do some when admin user enter the catalog list page. But it doesn't work for me.

Answer 1

You defined the instance of "ListProductObserver" in events.xml, but you named the class as "ListOwnerProductObserver"