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Content Template of Statically Defined Items and InsertAt

Dynamically adding Items to the PanelBar with the InsertAt() server-side method may cause the ContentTemplate of a statically defined Item (as shown below) to be lost after a subsequent postback.

ASPNET
<telerik:RadPanelBar RenderMode="Lightweight" ID="RadPanelBar1" runat="server" ExpandMode="SingleExpandedItem">
    <Items>
        <telerik:RadPanelItem Text="Item1">
            <ContentTemplate>
                <asp:Button runat="server" ID="Button1" Text="TemplateButton" OnClick="Button1_Click" />
            </ContentTemplate>
        </telerik:RadPanelItem>
    </Items>
</telerik:RadPanelBar> 

In order to avoid the issue with the ContentTemplate not instantiating properly, the insertion of the new PanelItem with InsertAt() must be performed in the PreInit event.

C#
protected void Page_PreInit(object sender, EventArgs e)
{
    RadPanelItem newItem = new RadPanelItem();
    newItem.Text = "New Item added in code-behind";

    RadPanelBar1.Items.Insert(0, newItem);
}
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