ThemeIndexerEvent example

'INSERT IGNORE INTO theme_child (child_id, parent_id) ( SELECT id as child_id, parent_theme_id as parent_id FROM theme WHERE parent_theme_id IS NOT NULL AND id IN (:ids) AND technical_name IS NULL ) ',
                ['ids' => Uuid::fromHexToBytesList($ids)],
                ['ids' => ArrayParameterType::STRING]
            );
        });

        $this->eventDispatcher->dispatch(new ThemeIndexerEvent($ids, $context, $message->getSkip()));
    }

    public function getTotal(): int
    {
        return $this->getIterator(null)->fetchCount();
    }

    public function getDecorated(): EntityIndexer
    {
        throw new DecorationPatternException(static::class);
    }