Add Additional Header Row To Grid

[Jimmy Hill]

I'm using Jason Maronge's code found here: http://www.telerik.com/community/forums/aspnet-ajax/grid/adding-multiple-header-rows-at-runtime-in-radgrid.aspx to add an additional header row to my grid. Here's my code:

void rgItemSummary_PreRender(object sender, EventArgs e)
    {
        //get the current header
        GridItem[] header = rgItemSummary.MasterTableView.GetItems(GridItemType.Header);

        //get the current THead element
        GridTHead head = ((GridTHead)header[0].Parent.Controls[0].Parent);

        //Get the GridHeaderItem from the THead
        GridHeaderItem currentHeaderItem = (GridHeaderItem)head.Controls[0];

        //Clear all GridHeaderItems
        head.Controls.Clear();

        //create a new GridHeaderItem which will be the new row
        GridHeaderItem newHeaderItem = new GridHeaderItem(rgItemSummary.MasterTableView, 0, 0);

        //Active column header
        GridTableHeaderCell itemInfoCell = new GridTableHeaderCell()
        {
            Text = "Item Info",
            ColumnSpan = 3,
            HorizontalAlign = HorizontalAlign.Center
        };

        //Period Data Header
        GridTableHeaderCell periodCell = new GridTableHeaderCell()
        {
            Text = "Period Data",
            ColumnSpan = 3,
            HorizontalAlign = HorizontalAlign.Center
        };

        //Current Available Header
        GridTableHeaderCell currentAvailableCell = new GridTableHeaderCell()
        {
            Text = "Current Available",
            ColumnSpan = 3,
            HorizontalAlign = HorizontalAlign.Center
        };

        newHeaderItem.Cells.Add(itemInfoCell);
        newHeaderItem.Cells.Add(periodCell);
        newHeaderItem.Cells.Add(currentAvailableCell);

        //Add back the GridHeaderItems in the order you want them to appear
        head.Controls.Add(newHeaderItem);
        head.Controls.Add(currentHeaderItem);
    }

 
Here's the problem: Only the "Current Available" cell is showing up. Any ideas what I'm doing wrong here?

EDIT: Assuming that the grid was only accepting the last cell that I added, I commented out newHeaderItem.Cells.Add(currentAvailableCell);. Oddly enough, that removed the Current Available but the other cells still were not added. When I step through the code, I can see that after newHeaderItem.Cells.Add(currentAvailableCell); is executed, the newHeaderItem object contains three controls. Why is only one being rendered?

[Pavlina]

Hi Jimmy Hill,

The only supported approach for having multiple header rows is currently using RadGrid's GridTemplateColumn (you can note the demo shows a 2-row header above the template column).

Kind regards,
Pavlina
the Telerik team