WishlistCollection keeps returning 0 products

Question

I'm trying to make a widget using the wishlist to show whether you've added the current product to the wishlist already or not. I've seen some other threads with answers and I can safely say I tried most if not all of them. Please help a beginning Magento 2 Dev out 🙏🏼

Wishlist has 3 items (Can be seen in the wishlist page and Database)

    /**
     * @param Product $inputProduct
     *
     * @return WishlistCollectionFactory
     */
    public function checkWishlistItem(Product $inputProduct)
    {

        $wishlistCollection = $this->_wishlistProvider->getWishlist()->getItemCollection();

        $wishlistItemList = [];

        /** @var Product $wishlistItem */
        foreach ($wishlistCollection as $wishlistItem) {
            array_add($wishlistItemList, 'product_id', $wishlistItem->getId());
        }

        return $wishlistCollection->addFieldToFilter('main_table.product_id', $inputProduct->getId());
    }

Other block I've tried:

$wishlistCollection = $this->_wishlistHelper->getWishlistItemCollection();
        $inWishlist = false;
        foreach ($wishlistCollection as $wishlistItem) {
            if ($inputProduct->getId() == $wishlistItem->getProduct()->getId()) {
                $inWishlist = true;
            }
        }

I have created a single php file that does all the work in Block/Widget. I can use all the feedback I can get so feel free to tell me another way of doing things if you feel like I'm doing things wrong.

Answer 1

Create WishlistProducts block To get Wishlist Products Collection, firstly, you need to create a WishlistProducts block. To do that, follow the path Vendor/ModuleName/Block/WishlistProducts.php and add the below code:

<?php

namespace Vendor\ModuleName\Block;
use Magento\Catalog\Block\Product\Context;
use Magento\Catalog\Model\Product\Visibility;
use Magento\Catalog\Model\ResourceModel\Product\CollectionFactory;
use Magento\Framework\App\Http\Context as HttpContext;
use Magento\Framework\Stdlib\DateTime\DateTime;
use Magento\Wishlist\Model\ResourceModel\Item\CollectionFactory as WishlistCollectionFactory;
use Vendor\ModuleName\Helper\Data;

class WishlistProducts extends AbstractSlider
{
    /**
     * @var WishlistCollectionFactory
     */
    protected $_wishlistCollectionFactory;
    /**
     * WishlistProducts constructor.
     * @param Context $context
     * @param CollectionFactory $productCollectionFactory
     * @param Visibility $catalogProductVisibility
     * @param DateTime $dateTime
     * @param Data $helperData
     * @param HttpContext $httpContext
     * @param WishlistCollectionFactory $wishlistCollectionFactory
     * @param array $data
     */
    public function __construct(
        Context $context,
        CollectionFactory $productCollectionFactory,
        Visibility $catalogProductVisibility,
        DateTime $dateTime,
        Data $helperData,
        HttpContext $httpContext,
        WishlistCollectionFactory $wishlistCollectionFactory,
        array $data = []
    ) {
        $this->_wishlistCollectionFactory = $wishlistCollectionFactory;
        parent::__construct($context, $productCollectionFactory, $catalogProductVisibility, $dateTime, $helperData, $httpContext, $data);
    }
    /**
     * @inheritdoc
     */
    public function getProductCollection()
    {
        $collection = [];
        if ($this->_customer->isLoggedIn()) {
            $wishlist = $this->_wishlistCollectionFactory->create()
                ->addCustomerIdFilter($this->_customer->getCustomerId());
            $productIds = null;
            foreach ($wishlist as $product) {
                $productIds[] = $product->getProductId();
            }
            $collection = $this->_productCollectionFactory->create()->addIdFilter($productIds);
            $collection = $this->_addProductAttributesAndPrices($collection)->addStoreFilter($this->getStoreId())->setPageSize($this->getProductsCount());
        }
        return $collection;
    }
}

Answer 2

I appreciate the help! Eventually I found out that using SessionFactory instead of Session worked out:

use Magento\Customer\Model\SessionFactory as Session;
use Magento\Wishlist\Model\Wishlist;

class FeaturedProducts extends Template implements BlockInterface
{

     /**
     * Session
     *
     * @var Session
     */
    private $_customerSession;

     /**
     * WishlistModel
     *
     * @var Wishlist
     */
    private $_wishlist;


     /**
     * Test constructor
     *
     * @param Context                   $context
     * @param Session                   $customerSession
     * @param Wishlist                  $wishlist
     * @param array                     $data
     */
    public function __construct(
        Context $context,
        Session $customerSession,
        Wishlist $wishlist,
        array $data = []
    ) {
        parent::__construct($context, $data);

        $this->_customerSession = $customerSession;
        $this->_wishlist = $wishlist;
    }

    public function getWishlistCollection()
    {

        $customerSession = $this->_customerSession->create();
        $isLoggedIn = $customerSession->isLoggedIn();
        if ($isLoggedIn) {
            $customer_id = $customerSession->getCustomerId();
            $wishlist_collection = $this->_wishlist->loadByCustomerId($customer_id, true)->getItemCollection();
        }
    }

}

I don't exactly know why this works and Session doesn't tho.