i have combobox that have value category1 and category2...the category1 have items like pencil,food,magazine,newspaper... when i choose category1, i want to retrieve the items in tdbmemo.then the same items in tdbmemo i want to display in checklistbox...i dont know how to do...i use clcat.items.add to display the item but the items is not display

procedure TfrmSysConfig.FillInCheckListClCat;  
var  
  sTable  : string;  
  sqlCat  : TIBOQuery;  
  iIndex :integer;  
  lstCat : TStringList;  
begin  
  if tblMain.FieldByName('POS_ReceiptCatBreakDown').AsString <> '' then begin  
     sqlCat := TIBOQuery.Create(nil);  
     sqlCat.IB_Connection := dmMain.db;  
     lstCat := TStringList.Create;  
     try  
       sqlCat.SQL.Text := 'SELECT code FROM ' + cboCategory.Value;  
       sqlCat.Open;  
       while not sqlCat.Eof do begin  
         clCat.Items.Add( sqlCat.FieldByName( 'Code' ).AsString );  
         sqlCat.Next;  
       end;  
     finally  
       lstCat.Free;  
       sqlCat.Free;  
     end;  
  end;  
end;