FileFieldAssembler::prepareRow

protected function prepareRow(array $row): array
{
	$row['columns'] ??= [];

	foreach ($this->getColumnIds() as $columnId)
	{
		$value = $row['data'][$columnId] ?? null;
		if ($value !== null || is_array($value))
		{
			// edit
			$row['data']['~' . $columnId] ??= $this->getDataForEdit($value);

			// view
			$row['columns'][$columnId] ??= $this->getImageHtml($columnId, $value);
		}
	}

	return $row;
}