Utility/DynamicFields.php
public function valid()
    {
        $isValid = true;

        foreach ($this->entities as $entity) {
            $isValid = $entity->valid();
            if (!$isValid) {
                break;
            }
        }

        return $isValid;
    }
public function valid()
    {
        $isValid = true;

        foreach ($this->entities as $entity) {
            $isValid = $entity->valid();
            if (!$isValid) {
                break;
            }
        }

        return $isValid;
    }
Check valid entity.

@return bool