Program can't find control within NestedViewTemplate.

[David]

I have a NestedViewTemplate which is based on the demo. Unfortunately it cannot find the Panel within it. What's going on with it?

<telerik:RadGrid ID="RadGrid1" runat="server" AllowFilteringByColumn="True" AllowPaging="True"
    AllowSorting="True" AutoGenerateColumns="False" DataSourceID="SqlDataSource1"
    GridLines="None" OnItemCommand="RadGrid1_ItemCommand" OnUpdateCommand="RadGrid1_UpdateCommand1"
    OnItemCreated="RadGrid1_ItemCreated">
    <MasterTableView DataSourceID="SqlDataSource1" Name="Client" CommandItemDisplay="Top"
        DataKeyNames="account_id,contact_id1,user_id">
        <CommandItemSettings ExportToPdfText="Export to Pdf"></CommandItemSettings>
        <DetailTables>
            <telerik:GridTableView DataKeyNames="user_id" runat="server" CommandItemDisplay="Top"
                CommandItemSettings-AddNewRecordText="Add New Accommodation" Caption="Accommodation"
                DataSourceID="SqlDataSource4" Width="100%" AutoGenerateColumns="false" AllowAutomaticDeletes="True"
                AllowAutomaticInserts="True" Name="Accommodation">
                <NestedViewTemplate>
                    <asp:Panel runat="server" ID="InnerContainer" Visible="false">
                        <telerik:RadTabStrip runat="server" ID="AccommodationTabStrip" MultiPageID="MultiPage1"
                            SelectedIndex="1">
                            <Tabs>
                                <telerik:RadTab runat="server" Text="Alternative Contacts" PageViewID="PageView1">
                                </telerik:RadTab>
                                <telerik:RadTab runat="server" Text="Features/Facilities" PageViewID="PageView2"
                                    Selected="True">
                                </telerik:RadTab>
                                <telerik:RadTab runat="server" Text="Gallery" PageViewID="PageView3">
                                </telerik:RadTab>
                                <telerik:RadTab runat="server" PageViewID="PageView5" Text="Bookings">
                                </telerik:RadTab>
                                <telerik:RadTab runat="server" Text="Statistics" PageViewID="PageView4">
                                </telerik:RadTab>
                            </Tabs>
                        </telerik:RadTabStrip>
                        <telerik:RadMultiPage runat="server" ID="MultiPage1" SelectedIndex="0" RenderSelectedPageOnly="false"
                            Width="656px">
                            <telerik:RadPageView runat="server" ID="PageView1">
                                <asp:Label ID="Label1" runat="server" Text='<%# Eval("user_id") %>'></asp:Label>
                                <telerik:RadGrid runat="server" ID="AccommContactsGrid" DataSourceID="SqlDataSource6"
                                    ShowFooter="True" AllowSorting="True" EnableLinqExpressions="False" AllowAutomaticDeletes="True"
                                    AllowAutomaticInserts="True" AllowAutomaticUpdates="True" AllowFilteringByColumn="True"
                                    AllowPaging="True" AutoGenerateColumns="False" GridLines="None">
                                    <MasterTableView ShowHeader="true" DataKeyNames="accom_id" PageSize="7" CommandItemDisplay="Top">
                                        <CommandItemSettings ExportToPdfText="Export to Pdf" />
                                        <CommandItemTemplate>
                                            <div style="padding: 5px 5px;">
                                                <asp:LinkButton ID="btnInsertAccom" CommandName="InitInsert" OnClientClick="return ShowInsertForm();"
                                                    runat="server"><img style="border: 0px; vertical-align:middle;" src="Images/03.png" />Add New Client Account</asp:LinkButton>
                                                <asp:LinkButton ID="btnOptionsAccom" CommandName="Options" runat="server" OnClientClick="return ShowOptionsForm();"><img style="border: 0px; vertical-align:middle;" src="Images/09.png" />Options</asp:LinkButton>
                                                <asp:LinkButton ID="btnRefreshAccom" CommandName="RebindGrid" runat="server"><img style="border: 0px; vertical-align:middle;" src="Images/21.png" />Refresh Link Group List</asp:LinkButton>
                                            </div>
                                        </CommandItemTemplate>
                                        <Columns>

And so forth ...

Here's the codenehind.

protected void RadGrid1_ItemCreated(object sender, GridItemEventArgs e)
{
    if (e.Item is GridNestedViewItem)
    {
        Panel panel = (Panel)e.Item.FindControl("InnerContainer");
        if (panel != null)
        {
            panel.Visible = ((GridNestedViewItem)e.Item).ParentItem.Expanded;
        }
    }
}

The panel != null is there to obviously avoid failure but TBH it's pointless using the NestedViewTemplate if the codebehind isn't going to pick up the embedded control. It happens elsewhere in the code as well.

[Princy]

Hello David,

Here is the sample code to access panel inside the NestedViewTemplate.

C#:

protected void RadGrid1_ItemDataBound(object sender, Telerik.Web.UI.GridItemEventArgs e)
 {
    if (e.Item is GridNestedViewItem && e.Item.OwnerTableView.Name =="Accommodation")
    {
       GridNestedViewItem nestedItem = (GridNestedViewItem)e.Item;
       Panel panel = (Panel)nestedItem.FindControl("InnerContainer");
       panel.Visible = ((GridNestedViewItem)e.Item).ParentItem.Expanded;
   }
}

Thanks,
Princy.