This example creates groups.
sheet.setRowCount(34);
sheet.setValue(0,0,"Western");
sheet.setValue(0,1,"Western");
sheet.setValue(0,2,"Western");
sheet.setValue(1,0,"A");
sheet.setValue(1,1,"B");
sheet.setValue(1,2,"C");
sheet.setValue(2,0,"A");
sheet.setValue(2,1,"B");
sheet.setValue(2,2,"C");
sheet.rowOutlines.group(0,2);
sheet.columnOutlines.group(0,1);
sheet.rowOutlines.expand(0,false);
sheet.columnOutlines.expand(0,false);
spread.invalidateLayout();
spread.repaint();
Object
GC.Spread.Sheets.Worksheet.rowOutlines