For a configurable product I want to get all related products of the linked simple products. How is it possible to merge multiple collections?
At the moment I overwrite the related products on each iteration of the foreach loop.
$product = $this->_coreRegistry->registry('product');
/* @var $product \Magento\Catalog\Model\Product */
if ($product->getTypeId() === 'configurable') {
$simpleProducts = $product->getTypeInstance()->getUsedProducts($product);
}
$relatedProductCollection = false;
/* @var $simpleProduct \Magento\Catalog\Model\Product */
foreach ($simpleProducts as $simpleProduct) {
/** @var $relatedProductCollection \Magento\Catalog\Model\ResourceModel\Product\Link\Product\Collection */
$relatedProductCollection = $simpleProduct->getRelatedProductCollection()->addAttributeToSelect(
'required_options'
)->setPositionOrder()->addStoreFilter();
}