Help On using RadPanelBar with DataTemple and Hiarchial DataTemplate

[Nivid]

I am using Hiearchial DataTemplates with normal DataTemplate that i saw in one of the forums in here. But i have a problem when the items are displayed properly but it is not expanded when clicked on the items. here is the code that i am using to Display two items at present.
The Link that i saw  this way to display can be found here

XAML:

 

 

 

 

 

<Window.Resources>
        <DataTemplate x:Key="PanelBarItemTemplate">
            <StackPanel Orientation="Vertical">
                <TextBlock Text="{Binding PropertyName}"/>
                <TextBlock Text="{Binding PropertyValue}"/>
                <TextBlock Text="{Binding Comments}"/>
            </StackPanel>
        </DataTemplate>

        <HierarchicalDataTemplate x:Key="PanelBarHeaderTemplate"
                           ItemsSource="{Binding Items,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}"
                           ItemTemplate="{StaticResource PanelBarItemTemplate}">
            <TextBlock Text="{Binding Title}" />
        </HierarchicalDataTemplate>

    </Window.Resources>

    <Grid>
        <DockPanel>
            <DockPanel DockPanel.Dock="Right" Width="350">
                <Label />
            </DockPanel>
            <DockPanel DockPanel.Dock="Right" VerticalAlignment="Bottom">
                <telerik:RadPanelBar ItemsSource="{Binding AccordionItems,UpdateSourceTrigger=PropertyChanged,Mode=TwoWay}"
                    ItemTemplate="{StaticResource PanelBarHeaderTemplate}" telerik:StyleManager.Theme="Windows7"/>
            </DockPanel>
        </DockPanel>
    </Grid>

C# ViewModel

public class MainViewModel:ViewModelBase
   {
       public MainViewModel()
       {
           _accordionItems = new List<AccoordionHelper>();
           AccordionItems = new List<AccoordionHelper>();
           _accordionItems.Add(new AccoordionHelper("OffFinalBill", new AccordionItemsHelper(){ Comments="hello", PropertyName="Off Final 1: ", PropertyValue= "12121" }));
           _accordionItems.Add(new AccoordionHelper("PartFinal", new AccordionItemsHelper() { Comments = "hello", PropertyName = "Off Final 1: ", PropertyValue = "12121" }));
           AccordionItems = _accordionItems;
       }
       private List<AccoordionHelper> _accordionItems = new List<AccoordionHelper>();
       public List<AccoordionHelper> AccordionItems
       {
           get
           {
               if (_accordionItems == null)
               {
                   _accordionItems = new List<AccoordionHelper>();
               }
               return _accordionItems;
           }
           set
           {
               _accordionItems = value;
               this.RaisePropertyChanged("AccordionItems");
           }
       }


   }
   public class AccoordionHelper:ViewModelBase
   {
       private string _title;
       public string Title
       {
           get
           {
               return _title;
           }
           set
           {
               _title = value;
               this.RaisePropertyChanged("Title");
           }
       }
       private AccordionItemsHelper _items;
       public AccordionItemsHelper Items
       {
           get
           {
               if (_items == null)
               {
                   _items = new AccordionItemsHelper();
               }
               return _items;
           }
           set
           {
               _items = value;
               this.RaisePropertyChanged("Items");
           }
       }
       public AccoordionHelper( string title, AccordionItemsHelper items)
       {
           Items=items;
           Title = title;
       }
   }
   public class AccordionItemsHelper
   {
       public string PropertyName { get; set; }
       public string PropertyValue { get; set; }
       public string Comments { get; set; }
   }

[Petar Mladenov]

Hello,

 The RadPanelBar inherits from RadTreeView and they are both HierarChical controls. They are ItemControls - they are consisted of Items and their containers : RadPanelBarItems (or RadTreeViewItems) have Items property too. So when you bind your first level's ItemsSource collection:

<HierarchicalDataTemplate x:Key="PanelBarHeaderTemplate"
                   ItemsSource="{Binding Items,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}"
                   ItemTemplate="{StaticResource PanelBarItemTemplate}">
    <TextBlock Text="{Binding Title}" />
</HierarchicalDataTemplate>

the RadPanelBar expects collection of objects but you provide a single object:

public class AccoordionHelper:ViewModelBase
   {
       private string _title;
       public string Title
       {
           get
           {
               return _title;
           }
           set
           {
               _title = value;
               this.RaisePropertyChanged("Title");
           }
       }
       private AccordionItemsHelper _items;
       public AccordionItemsHelper Items
       {
           get

 Making this Items property a List of AccordionItemsHelper s will solve your scenario as it is done in the attached project. Feel free to ask if you need further assistance.

Greetings,
Petar Mladenov
the Telerik team