Article information
Article relates to	TreeView ItemTemplateSelector
Created by	Boryana Miloshevska
Last modified	11.23.2009
Last modified by

All you need to do if you want to set ItemTemplateSelector is the following:
1.Create a class that derives from DataTemplateSelector and add the desired templates as public properties :
 public class LeagueDataTemplateSelector : DataTemplateSelector
    {
        public HierarchicalDataTemplate LeagueTemplate
        {
            get;
            set;
        }

        public HierarchicalDataTemplate DivisionTemplate
        {
            get;
            set;
        }
        public DataTemplate TeamTemplate
        {
            get;
            set;
        }

        public LeagueDataTemplateSelector()
        {
        }

        public override DataTemplate SelectTemplate(object item, DependencyObject container)
        {
            base.SelectTemplate(item, container);

            if (item is League)
            {
                return this.LeagueTemplate;
            }
            else if (item is Division)
            {
                return this.DivisionTemplate;
            }
            else if (item is Team)
            {
                return this.TeamTemplate;
            }
            return null;
        }
    }

2.In the XAML define the following resources:
 <UserControl.Resources>
        <ds:LeaguesDataSource x:Key="MyList" />

        <DataTemplate x:Key="Team">
            <StackPanel Orientation="Horizontal">
                <Image Source="{Binding Image}" Margin=" 0,0,6,0"/>
                <TextBlock Text="{Binding Name}" Foreground="Blue" FontWeight="Bold" FontSize="9" />
            </StackPanel>
        </DataTemplate>

        <core:HierarchicalDataTemplate x:Key="Division" ItemsSource="{Binding Teams}">
            <StackPanel Orientation="Horizontal">
                <Image Source="{Binding Image}" Margin=" 0,0,6,0" />
                <TextBlock Text="{Binding Name}" Foreground="Green"  FontWeight="Bold" FontSize="12" />
            </StackPanel>
        </core:HierarchicalDataTemplate>

        <core:HierarchicalDataTemplate x:Key="League" ItemsSource="{Binding Divisions}">
            <StackPanel Orientation="Horizontal">
                <Image Source="{Binding Image}" Margin=" 0,0,6,0" />
                <TextBlock Text="{Binding Name}" Foreground="Black" FontWeight="Bold" FontSize="15" />
            </StackPanel>
        </core:HierarchicalDataTemplate>
        <ds:LeagueDataTemplateSelector x:Key="myDataTemplateSelector" LeagueTemplate="{StaticResource League}" TeamTemplate="{StaticResource Team}" DivisionTemplate="{StaticResource Division}"/>
    </UserControl.Resources>

Note: The important thing here is not to forget to set all template properties:

<ds:LeagueDataTemplateSelector x:Key="myDataTemplateSelector" LeagueTemplate="{StaticResource League}" TeamTemplate="{StaticResource Team}" DivisionTemplate="{StaticResource Division}"/>

3.Now you are ready to apply the ItemTemplateSelector to the treeview:
<telerikNavigation:RadTreeView Width="290"
                ItemTemplateSelector="{StaticResource myDataTemplateSelector}"
                ItemsSource="{Binding Source={StaticResource MyList}}" />

That is all you need to do in order to set the ItemTemplateSelector of a RadTreeView.