<telerik:RadPanelBar ID="RadPanelBar1" runat="server"> 
        <Items> 
            <telerik:RadPanelItem runat="server" Text="Activities"> 
                <Items> 
                    <telerik:RadPanelItem runat="server" Value="templateHolder"> 
                        <ItemTemplate> 
                            <asp:CheckBox ID="CheckBox2" runat="server" /> 
                        </ItemTemplate> 
                    </telerik:RadPanelItem> 
                </Items> 
            </telerik:RadPanelItem> 
        </Items>  
 </telerik:RadPanelBar>

This is my  .ascx.cs file:

public override void DoLayout( )
  {
     //Get collection
     TrackableCollection<ProjectActivityBooking> acitivities = existingRegistration.ProjectParticipant.ProjectEntity.ProjectActivityBooking;
     //Here it is possible to get hold of the checkbox
     CheckBox cb = RadPanelBar1.FindItemByValue("templateHolder").FindControl("CheckBox2") as CheckBox;
     //Add datasource and bind
     this.RadPanelBar1.ItemDataBound += new RadPanelBarEventHandler(itemDatabound);
     this.RadPanelBar1.DataSource = acitivities;
     this.RadPanelBar1.DataBind();
  }

The code below let me add a new instatited CheckBox, but it is not added as subitem. Instead I´m getting a "static" RadPanelBar without the nice feature of being pushed and sliding out the subitems ie. activities

void itemDatabound(Object sender, RadPanelBarEventArgs e)
  {
     //Get panelItem
     RadPanelItem item = (RadPanelItem)e.Item;
     //Create Checkbox
     CheckBox chk = new CheckBox();
     //Get Activity
     ProjectActivityBooking activity =  item.DataItem as ProjectActivityBooking;
     //Set activity name
     chk.Text = activity.ProjectActivity.ActivityName;
     //Add control
     item.Controls.Add(chk);
   }

I think the way forward is something like below, but that will not get me my CheckBox.
void itemDatabound(Object sender, RadPanelBarEventArgs e)
{
   //This will throw an exception
   //CheckBox cb1 = RadPanelBar1.FindItemByValue("templateHolder").FindControl("CheckBox2") as CheckBox;
   //This will return null as it will now find the templateHolder RadPanel item
   //How will I then get hold of the CheckBox2 when the templateholder do not find/returns null
   //RadPanelItem item = e.Item.FindControl("templateHolder") as RadPanelItem;
}

Please let me know what I´ve done wrong?

Best Regards,

Thomas Andersson