protected function calculateWidth(array $items, string $marker): array
	{
		$count = 0;

		foreach($items as $item)
		{
			if(!is_array($item))
			{
				$count++;
			}
		}

		$number = strlen($count);

		$marker = strlen(sprintf($this->formatter === null ? $marker : $this->formatter->stripTags($marker), '')) + $number;

		return ['number' => $number, 'marker' => $marker];
	}