Call to a member function getRelatedProductCollection() on null

Question

I get this error when I go to any page where there aren't any related products displayed.

Error:

( ! ) Fatal error: Uncaught Error: Call to a member function getRelatedProductCollection() on null in C:\wamp64\www\magento2\app\code\Test\RelatedProducts\Block\Product.php on line 88

Method where line 88 is located:

public function getRelatedProducts()
{
    $relatedProducts = $this
        ->getProduct()
        ->getRelatedProductCollection()
        ->addAttributeToSelect(['price','name','image','status']);

    return $relatedProducts;
}

Constructor:

public function __construct(
    StoreManagerInterface $storeManager,
    Currency $currency,
    Context $context,
    Registry $registry,
    array $data = []
) {
    $this->_storeManager = $storeManager;
    $this->_currency = $currency;
    $this->_registry = $registry;
    parent::__construct($context, $data);
}

EDIT:

If I add if($this->getProduct() != null) to getRelatedProducts() then everything is fine.

/**
 * Return current product
 *
 * @return mixed
 */
public function getProduct()
{
    return $this->_registry->registry('product');
}

/**
 * Return collection of related products from the current product
 *
 * @return mixed
 */
public function getRelatedProducts()
{
    if($this->getProduct() != null){
        $relatedProducts = $this
            ->getProduct()
            ->getRelatedProductCollection()
            ->addAttributeToSelect(['price','name','image','status']);

        $relatedProducts->getSelect()->orderRand();

        return $relatedProducts->getItems();
    }
}

Answer 1

Seem that $this->getProduct() or getRelatedProductCollection()returns null value. You need to check this.

For example:

if($this->getProduct() != null)