getItemCollection() returns null always magento 2.3

Question

i have created an remove wishlist rest api, i am passing customerid & productid to "removeWishlistForCustomer()" but getItemCollection() always returns null, so i can't delete wishlist items.

Please take a look at the below code & share your thoughts on this.

<?php


namespace Vueapi\Wishlist\Model;

use Vueapi\Wishlist\Api\WishlistManagementInterface;
use Magento\Customer\Model\CustomerRegistry;
use Magento\Framework\Exception\LocalizedException;
use Magento\Wishlist\Controller\WishlistProvider;
use Magento\Wishlist\Controller\WishlistProviderInterface;
use Magento\Wishlist\Model\Item;
use Magento\Wishlist\Model\ResourceModel\Item\CollectionFactory;
use Magento\Wishlist\Model\WishlistFactory;

/**
 * Defines the implementaiton class of the WishlistManagementInterface
 */
class WishlistManagement implements WishlistManagementInterface
{

    /**
     * @var WishlistProviderInterface
     */
    protected $wishlistProvider;
    private $wishlist;
    /**
     * @var CollectionFactory
     */
    protected $_wishlistCollectionFactory;
    /**
     * @var CustomerRegistry
     */
    protected $_wishlistFactory;
    /**
     *@var \Magento\Catalog\Model\Product
     */
    private $_objectManager;

    protected $_productload;
    /**
     *
     * @var \Magento\Store\Model\StoreManagerInterface
     */
    protected $storemanagerinterface;
    protected $customerRegistry;

    public function __construct(
        CustomerRegistry $customerRegistry,
        \Magento\Framework\ObjectManagerInterface $objectmanager,
        WishlistProviderInterface $wishlistProvider,
        \Magento\Catalog\Model\ProductFactory $_productloader,
        \Magento\Store\Model\StoreManagerInterface $storemanagerinterface,
        \Magento\Wishlist\Model\ResourceModel\Item\CollectionFactory $_wishlistCollectionFactory,
        \Magento\Wishlist\Model\WishlistFactory $wishlistFactory,
        \Magento\Wishlist\Model\Wishlist $wishlist

    ) {
        $this->_objectManager             = $objectmanager;
        $this->wishlistProvider           = $wishlistProvider;
        $this->wishlist                   = $wishlist;
        $this->_productloader             = $_productloader;
        $this->_wishlistFactory           = $wishlistFactory;
        $this->_wishlistCollectionFactory = $_wishlistCollectionFactory;
        $this->storemanagerinterface      = $storemanagerinterface;
        $this->customerRegistry           = $customerRegistry;
    }

    public function removeWishlistForCustomer($customerId, $productId)
    {
        $wish  = $this->wishlist->loadByCustomerId($customerId);
        $items = $wish->getItemCollection();
        foreach ($items as $item) {
            if ($item->getProductId() == $productId) {
                $item->delete();
                $wish->save();
                return 'Product removed from wishlist';
            }
        }
    }

}

Answer 1

It can be because of two reason

1. the given customer id has no wish list
2. or the wishlist instance is not created correctly. You should always get fresh instance.

Try changing your code to

public function removeWishlistForCustomer($customerId, $productId)
{
    $wish = $this->wishlistFactory->create()
                ->loadByCustomerId($customerId, true);
    $items = $wish->getItemCollection()->load();
    foreach ($items as $item) {
        if ($item->getProductId() == $productId) {
            $item->delete();
            return 'Product removed from wishlist';
        }
    }
}