Why getParentsIdsByChild($productId); is returning empty for Child product?

Question

I'm trying to get parent products id for child products but i'm getting empty result.

<?php


namespace CustomColumn\Addproductcolumn\Ui\Component\Listing\Column;
use Magento\Framework\View\Element\UiComponentFactory;
use Magento\Framework\View\Element\UiComponent\ContextInterface;
use Magento\Ui\Component\Listing\Columns\Column;

class ParentProductId extends Column
{
    protected $configurable;
    public function __construct(
        ContextInterface $context,
        UiComponentFactory $uiComponentFactory,
        \Magento\ConfigurableProduct\Model\ResourceModel\Product\Type\Configurable $configurable,
        array $components = [],
        array $data = []
    ) {
        parent::__construct($context, $uiComponentFactory, $components, $data);
        $this->_configurable = $configurable;
    }

    public function prepareDataSource(array $dataSource)
    {

        if (isset($dataSource['data']['items'])) {
            foreach ($dataSource['data']['items'] as &$items) {

            if($items['type_id'] == 'simple'){

                $productId = $items['entity_id'];
                $getParent = $this->_configurable->getParentIdsByChild($productId);

                if($getParent){
                    $items['parentid_col'] = $getParent[0];
                }else{
                    $items['parentid_col'] = "nothing found";
                }
            }
        }
    }
        return $dataSource;
    }
}
?>

Answer 1

You should try

For Configurable Product

\Magento\ConfigurableProduct\Model\Product\Type\Configurable $configurable;

$this->_configurable->getParentIdsByChild($productId);

For Bundle Product

\Magento\Bundle\Model\ResourceModel\Selection $bundleSelection;

$this->bundleSelection->getParentIdsByChild($productId);

Also please make sure that you are getting correct simple product ID which is assigned to Configurable product.