Magento – Create ‘Catalog Input Type for Store Owner’

Ultimately, I relied on my instinct rather than on poorly written tutorials.

Instantiate new models for each option and each option's values. This is the key.

$product = $o->getEvent()->getProduct();
$optionModel = Mage::getModel('catalog/product_option')
    ->setTitle('My title')
    ->setProductId($product->getId())
    ->setStoreId($product->getStoreId())
    ->setId($myOptionId)
    ->setType('radio')
    ->setPrice(null)
    ->setPriceType(null)
    ->setSku($myOptionSku)
    ->setIsRequire(true);

$myValues = getModel('my_module/custom_model')->getCollection();

foreach ($myValues as $myValue) {
    $valueModel = Mage::getModel('catalog/product_option_value')
        ->setTitle($myValue->getDescription())
        ->setProduct($product)
        ->setOption($optionModel)
        ->setId($myValue->getId())
        ->setPrice($myValue->getMultiplier())
        ->setPriceType('fixed')
        ->setSku($myValue->getDescription());
    $optionModel->addValue($valueModel);
}
$product->setHasOptions(1);
$product->addOption($optionModel);

In Fun/Tablegrid/Model/Catalog/ResourceModel/Attribute.php, try:

protected function _beforeSave(\Magento\Framework\Model\AbstractModel $object){
    if ($object->getFrontendInput() === 'tableinput'){
        $object->setBackendType('text');
        /* Use setData() and specify full class name below */
        $object->setData('frontend_input_renderer', 'Endertech\Numeric\Block\Adminhtml\Attribute\Numeric');
    }
    return parent::_beforeSave($object);
}