Magento 2.3 - Load product by id

Question

I try to load a product by it's ID into my block template. Currently I am using this code which works fine:

$objectManager = \Magento\Framework\App\ObjectManager::getInstance();
$_product = $objectManager->get('Magento\Catalog\Model\Product')->load($item->getProductId());

But I heard that this is not clean. How can I improve this?

I tried it like this:

Block:

<?php

namespace Anshu\Bestsellerwidget\Block\Product\Widget;

use \Magento\Catalog\Model\ProductRepository;

class BestsellerWidget extends \Magento\Framework\View\Element\Template implements \Magento\Widget\Block\BlockInterface
{
    protected $_productRepository;

    public function __construct(
        \Magento\Catalog\Block\Product\Context $context,
        ...
        ProductRepository $productRepository,
        array $data = []
    ) {
        ...
        $this->_productRepository = $productRepository;
        parent::__construct($context, $data);
    }

    public function getProductById($id)
    {
        return $this->_productRepository->getById($id);
    }

    ...
}

Template:

$_product = $block->getProductById($item->getProductId());

But I get Type Error occurred when creating object: Anshu\Bestsellerwidget\Block\Product\Widget\BestsellerWidget

UPDATE

I found this in Magento/var/log/system.log:

Type Error occurred when creating object: Anshu\Bestsellerwidget\Block\Product\Widget\BestsellerWidget, Argument 5 passed to Anshu\Bestsellerwidget\Block\Product\Widget\BestsellerWidget::__construct() must be an instance of Magento\Catalog\Model\ProductRepository, array given, called in /srv/www/vhosts/hausfux_m2/vendor/magento/framework/ObjectManager/Factory/AbstractFactory.php on line 116 [] []

NOTE: Argument 5 is the line ProductRepository $productRepository, in the constructor

Answer 1

I had to delete the folder generated/code, then I executed sudo -u projectuser php bin/magento setup:upgrade. Now it works.

It can be enough to just execute the command without having to delete the folder first.

There was nothing wrong with the code, only with magento.

Answer 2

The issue is because the arguments you are passing with the parent::__construct methods are wrong.

The parent function requires \Magento\Framework\View\Element\Template\Context while you are passing \Magento\Catalog\Block\Product\Context as your context object.

Change the class with \Magento\Framework\View\Element\Template\Context and it should resolve your issue.