code: private function writeDimension(XMLWriter $objWriter, PhpspreadsheetWorksheet $pSheet)
      {
          // dimension
          $objWriter->startElement('dimension');
          $objWriter->writeAttribute('ref', $pSheet->calculateWorksheetDimension());
          $objWriter->endElement();
      }
docs: Write Dimension.
  
  @param XMLWriter $objWriter XML Writer
  @param PhpspreadsheetWorksheet $pSheet Worksheet