public function addChild(SwatObject $child)
    {
        if ($child instanceof SwatDetailsViewField) {
            $this->appendField($child);
        } else {
            $class_name = get_class($child);

            throw new SwatInvalidClassException(
                "Unable to add '{$class_name}' object to SwatDetailsView. " .
                    'Only SwatDetailsViewField objects may be nested within ' .
                    'SwatDetailsView objects.',
                0,
                $child
            );
        }
    }