telerik:RadGrid ID="RadGrid1" runat="server" OnNeedDataSource="RadGrid1_NeedDataSource">

<MasterTableView AutoGenerateColumns="false">

<Columns>

<telerik:GridBoundColumn DataField="ID" visible="true"></telerik:GridBoundColumn>

<telerik:GridDropDownColumn HeaderText="Document type" UniqueName="DocType" DataField="DocVal"

ListTextField="SubmitForm" ListValueField="DocVal" DropDownControlType="DropDownList"

EnableEmptyListItem="true" EmptyListItemText="---Choose an option--">

</telerik:GridDropDownColumn>

<telerik:GridTemplateColumn HeaderText="File to upload" UniqueName="TemplateColumn1">

<ItemTemplate>

<asp:FileUpload ID="FileUpload1" runat="server" />

</ItemTemplate>

</telerik:GridTemplateColumn>

<telerik:GridTemplateColumn HeaderText="Will Fax Later" UniqueName="TemplateColumn2">

<ItemTemplate>

<asp:CheckBox ID="FaxLater" runat="server" />

</ItemTemplate>

</telerik:GridTemplateColumn>

<telerik:GridTemplateColumn HeaderText="Status" UniqueName="TemplateColumn3">

<ItemTemplate>

<asp:Label ID="Status" runat="server" Text=" "></asp:Label>

</ItemTemplate>

</telerik:GridTemplateColumn>

</Columns>

</MasterTableView>

</telerik:RadGrid>

Dim i As Integer

For i = 0 To FileCount - 1

arr.Add(FileCount)

Next

'Dim ddl As DropDownList

'ddl = RadGrid1.Items("TemplateColumn").FindControl("DDL1")

'ddl.DataSource = ds

'ddl.DataBind()

Dim table As DataTable = New DataTable()

table.Columns.Add(

"ID")

table.Columns.Add(

"SubmitForm")

table.Columns.Add(

"DocVal")

For i = 0 To arr.Count - 1

Dim row As DataRow = table.NewRow()

row(

"ID") = i

row(

"SubmitForm") = ds.Tables(0).Rows(i).Item(1)

row(

"DocVal") = ds.Tables(0).Rows(i).Item(0)

table.Rows.Add(row)

Next

True

ds is a dataset populated with two columns, DocVal and SubmitForm.
arr is an Array. 

I'm in kind of a bind here.  I've been beating my head on the wall with this all day.  Any help would be greatly appreciated.

I can't figure it out.  I have AllowFilteringByColumn set to true on the main grid, so I thought it was supposed to allow it for all underlying tables, but everytime I attempt filtering a details table, I get a blank screen.

Here's the code:
aspx:
<telerik:RadGrid ID="RadGrid1" runat="server" AllowFilteringByColumn="True"
        AllowPaging="True" AllowSorting="True" GridLines="None"
        ondetailtabledatabind="RadGrid1_DetailTableDataBind"
        onneeddatasource="RadGrid1_NeedDataSource" Skin="WebBlue">
       
        <MasterTableView AutoGenerateColumns="false" DataKeyNames="ProjNo">
            <DetailTables>
                <telerik:GridTableView runat="server" ShowFooter="True">
                    <RowIndicatorColumn>
                        <HeaderStyle Width="20px" />
                    </RowIndicatorColumn>
                    <ExpandCollapseColumn>
                        <HeaderStyle Width="20px" />
                    </ExpandCollapseColumn>
                </telerik:GridTableView>
            </DetailTables>
            <RowIndicatorColumn>
                <HeaderStyle Width="20px"></HeaderStyle>
            </RowIndicatorColumn>
            <ExpandCollapseColumn Visible="True">
                <HeaderStyle Width="20px"></HeaderStyle>
            </ExpandCollapseColumn>
            <Columns>
            <telerik:GridBoundColumn DataField="ProjNo" DataType="System.Int32"
            HeaderText="Project Number" ReadOnly="True" SortExpression="ProjNo"
            UniqueName="ProjNo">
        </telerik:GridBoundColumn>
        <telerik:GridBoundColumn DataField="ProjectName" HeaderText="Project Name"
            SortExpression="ProjectName" UniqueName="ProjectName">
        </telerik:GridBoundColumn>
        <telerik:GridBoundColumn DataField="DateCreated" DataType="System.DateTime"
            HeaderText="Date Created" SortExpression="DateCreated"
            UniqueName="DateCreated">
        </telerik:GridBoundColumn>
        <telerik:GridBoundColumn DataField="ProjectStatus" HeaderText="Project Status"
            SortExpression="ProjectStatus" UniqueName="ProjectStatus">
        </telerik:GridBoundColumn>
        <telerik:GridBoundColumn DataField="POCName" HeaderText="Point Of Contact"
            ReadOnly="True" SortExpression="POCName" UniqueName="POCName">
        </telerik:GridBoundColumn>
            </Columns>
        </MasterTableView>
        <ClientSettings>
            <Scrolling AllowScroll="True" UseStaticHeaders="True" />
        </ClientSettings>
        <FilterMenu EnableTheming="True" Skin="Vista">
            <CollapseAnimation Type="OutQuint" Duration="200">
            </CollapseAnimation>
        </FilterMenu>
       
    </telerik:RadGrid>

CODE BEHIND:

private string user = "jrpuser";
    protected void Page_Load(object sender, EventArgs e)
    {

    }
    protected void RadGrid1_NeedDataSource(object source, Telerik.Web.UI.GridNeedDataSourceEventArgs e)
    {
        GridData gd = new GridData();
        RadGrid1.DataSource = gd.GetProjects(user);
    }
    protected void RadGrid1_DetailTableDataBind(object source, Telerik.Web.UI.GridDetailTableDataBindEventArgs e)
    {
        GridData gd = new GridData();
        GridDataItem masterItem = (GridDataItem)e.DetailTableView.ParentItem;
        e.DetailTableView.DataSource = gd.GetProjectDetails(user, Convert.ToInt16(masterItem.GetDataKeyValue("ProjNo")));
    }

BUSINESS OBJECTS:

public DataTable GetProjects(string user)
        {
            SqlDataAdapter da = null;
            DataTable table = new DataTable();
            SqlConnection conn = null;
            SqlCommand cmd = null;
            string connection;
            piiConnection strcon = new piiConnection();
            try
            {
                connection = strcon.getConnection();
                conn = new SqlConnection(connection);
                cmd = new SqlCommand("spGetProjects", conn);
                cmd.CommandType = System.Data.CommandType.StoredProcedure;
                cmd.Parameters.Add(new SqlParameter("@User", user));
                da = new SqlDataAdapter(cmd);
                conn.Open();
                da.Fill(table);
            }
            finally
            {
                conn.Close();
            }
            return table;
        }
        public DataTable GetProjectDetails(string user, int id)
        {
            SqlDataAdapter da = null;
            DataTable table = new DataTable();
            SqlConnection conn = null;
            SqlCommand cmd = null;
            string connection;
            piiConnection strcon = new piiConnection();

            try
            {
                connection = strcon.getConnection();
                conn = new SqlConnection(connection);
                cmd = new SqlCommand("spGetProjectDetails", conn);
                cmd.CommandType = System.Data.CommandType.StoredProcedure;
                cmd.Parameters.Add(new SqlParameter("@User", user));
                cmd.Parameters.Add(new SqlParameter("@ProjNo", id));
                da = new SqlDataAdapter(cmd);
                conn.Open();
                da.Fill(table);
            }
            finally
            {
                conn.Close();
            }
            return table;
        }