Hi Rafal,
If your intension is to have the first column of data source to be appeared as the row header column, one way to achieve the desired behavior by hiding the default row header and by handling the QueryCellStyleInfo event make the first column as Header. See the code and sample:
this.gridGroupingControl1.TableModel.Properties.RowHeaders = false;
this.gridGroupingControl1.QueryCellStyleInfo += new Syncfusion.Windows.Forms.Grid.Grouping.GridTableCellStyleInfoEventHandler(gridGroupingControl1_QueryCellStyleInfo);
void gridGroupingControl1_QueryCellStyleInfo(object sender, Syncfusion.Windows.Forms.Grid.Grouping.GridTableCellStyleInfoEventArgs e)
{
if (e.TableCellIdentity.ColIndex == 1)
e.Style.CellType = "Header";
}
Sample:
http://files.syncfusion.com/support/Grid.Windows/F88735.zipPlease let me know if this helps.
Regards,
Jisha