Pimcore\Model\Object\ClassDefinition\Data\Fieldcollections::setAllowedTypes PHP Method

    public function setAllowedTypes($allowedTypes)
    {
        if (is_string($allowedTypes)) {
            $allowedTypes = explode(",", $allowedTypes);
        }
        if (is_array($allowedTypes)) {
            for ($i = 0; $i < count($allowedTypes); $i++) {
                try {
                    Object\Fieldcollection\Definition::getByKey($allowedTypes[$i]);
                } catch (\Exception $e) {
                    Logger::warn("Removed unknown allowed type [ {$allowedTypes[$i]} ] from allowed types of field collection");
                    unset($allowedTypes[$i]);
                }
            }
        }
        $this->allowedTypes = (array) $allowedTypes;
        $this->allowedTypes = array_values($this->allowedTypes);
        // get rid of indexed array (.join() doesnt work in JS)
        return $this;
    }