PHPExcel how to insert empty row?

Question

PHP

How to insert a blank line after the last line in a sheet?

$num_rows = $xls->getActiveSheet()->getHighestRow();
 //there need to insert a blank new row 
 $sheet->fromArray($header,null, "A".($num_rows + 1));

Tried to insert just empty data, but they are ignored.
Tell me please. Thanks in advance!

Answer 1

it seems, at the excel level, blank lines are ignored.