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Binding to Object

To bind the RadTreeView to a collection use its ItemsSource property and define HierarchicalDataTemplate that are needed to display the data from the collection. If you want the changes to the collection to be automatically reflected to the RadTreeView items, the collection should inherit from ObservableCollection, or to implement the INotifyPropertyChanged interface.

The following tutorial will guide you how to bind a RadTreeView to a collection of business objects.

The final result should look like the snapshot below:

  • First, you need to include the following assemblies in your XAML declaration:

    • Telerik.Windows.Controls
    • Telerik.Windows.Controls.Navigation
  • Create a new class named Team. The class has a single string property.

        public class Team
        {
            public Team( string name )
            {
                this.Name = name;
            }
            public string Name
            {
                get;
                set;
            }
        }
    
        Public Class Team
            Public Sub New(ByVal name As String)
                Me.Name = name
            End Sub
    
        Private _Name As String
            Public Property Name() As String
                Get
                    Return _Name
                End Get
                Set(ByVal value As String)
                    _Name = value
                End Set
            End Property
        End Class
    
  • Create a new class named Division. The class has a single string property - Name and a collection with teams.

        public class Division
        {
            public Division( string name )
            {
                this.Name = name;
                this.Teams = new ObservableCollection<Team>();
            }
            public string Name
            {
                get;
                set;
            }
            public ObservableCollection<Team> Teams
            {
                get;
                set;
            }
        }
    
        Public Class Division
            Public Sub New(ByVal name As String)
                Me.Name = name
                Me.Teams = New ObservableCollection(Of Team)()
            End Sub
    
        Private _Name As String
            Public Property Name() As String
                Get
                    Return _Name
                End Get
                Set(ByVal value As String)
                    _Name = value
                End Set
            End Property
    
        Private _Teams As ObservableCollection(Of Team)
            Public Property Teams() As ObservableCollection(Of Team)
                Get
                    Return _Teams
                End Get
                Set(ByVal value As ObservableCollection(Of Team))
                    _Teams = value
                End Set
            End Property
        End Class
    
  • Create a new class named League. The class has a single string property and a collection with divisions objects. Practically, a collection of League objects will be the data source for the treeview.

        public class League
        {
            public League( string name )
            {
                this.Name = name;
                this.Divisions = new ObservableCollection<Division>();
            }
            public string Name
            {
                get;
                set;
            }
            public ObservableCollection<Division> Divisions
            {
                get;
                set;
            }
        }
    
        Public Class League
            Public Sub New(ByVal name As String)
                Me.Name = name
                Me.Divisions = New ObservableCollection(Of Division)()
            End Sub
    
        Private _Name As String
            Public Property Name() As String
                Get
                    Return _Name
                End Get
                Set(ByVal value As String)
                    _Name = value
                End Set
            End Property
    
        Private _Divisions As ObservableCollection(Of Division)
            Public Property Divisions() As ObservableCollection(Of Division)
                Get
                    Return _Divisions
                End Get
                Set(ByVal value As ObservableCollection(Of Division))
                    _Divisions = value
                End Set
            End Property
        End Class
    
  • Create a new class named RadTreeViewSampleData. This will be the data source (the model) for the RadTreeView. The class has a reference to an ObservableCollection of League objects and a single method which initializes the data.

        public class RadTreeViewSampleData
        {
            public RadTreeViewSampleData()
            {
                this.InitializeLeaguesDataSource();
            }
            public ObservableCollection<League> LeaguesDataSource
            {
                get;
                set;
            }
            private void InitializeLeaguesDataSource()
            {
                this.LeaguesDataSource = new ObservableCollection<League>();
                League l;
                Division d;
                this.LeaguesDataSource.Add( l = new League( "League A" ) );
                l.Divisions.Add( ( d = new Division( "Division A" ) ) );
                d.Teams.Add( new Team( "Team I" ) );
                d.Teams.Add( new Team( "Team II" ) );
                d.Teams.Add( new Team( "Team III" ) );
                d.Teams.Add( new Team( "Team IV" ) );
                d.Teams.Add( new Team( "Team V" ) );
                l.Divisions.Add( ( d = new Division( "Division B" ) ) );
                d.Teams.Add( new Team( "Team Blue" ) );
                d.Teams.Add( new Team( "Team Red" ) );
                d.Teams.Add( new Team( "Team Yellow" ) );
                d.Teams.Add( new Team( "Team Green" ) );
                d.Teams.Add( new Team( "Team Orange" ) );
                l.Divisions.Add( ( d = new Division( "Division C" ) ) );
                d.Teams.Add( new Team( "Team East" ) );
                d.Teams.Add( new Team( "Team West" ) );
                d.Teams.Add( new Team( "Team North" ) );
                d.Teams.Add( new Team( "Team South" ) );
                this.LeaguesDataSource.Add( l = new League( "League B" ) );
                l.Divisions.Add( ( d = new Division( "Division A" ) ) );
                d.Teams.Add( new Team( "Team 1" ) );
                d.Teams.Add( new Team( "Team 2" ) );
                d.Teams.Add( new Team( "Team 3" ) );
                d.Teams.Add( new Team( "Team 4" ) );
                d.Teams.Add( new Team( "Team 5" ) );
                l.Divisions.Add( ( d = new Division( "Division B" ) ) );
                d.Teams.Add( new Team( "Team Diamond" ) );
                d.Teams.Add( new Team( "Team Heart" ) );
                d.Teams.Add( new Team( "Team Club" ) );
                d.Teams.Add( new Team( "Team Spade" ) );
                l.Divisions.Add( ( d = new Division( "Division C" ) ) );
                d.Teams.Add( new Team( "Team Alpha" ) );
                d.Teams.Add( new Team( "Team Beta" ) );
                d.Teams.Add( new Team( "Team Gamma" ) );
                d.Teams.Add( new Team( "Team Delta" ) );
                d.Teams.Add( new Team( "Team Epsilon" ) );
            }
        }
    
        Public Class RadTreeViewSampleData
            Public Sub New()
                Me.InitializeLeaguesDataSource()
            End Sub
    
        Private _LeaguesDataSource As ObservableCollection(Of League)
            Public Property LeaguesDataSource() As ObservableCollection(Of League)
                Get
                    Return _LeaguesDataSource
                End Get
                Set(ByVal value As ObservableCollection(Of League))
                    _LeaguesDataSource = value
                End Set
            End Property
    
            Private Sub InitializeLeaguesDataSource()
                Me.LeaguesDataSource = New ObservableCollection(Of League)()
                Dim l As League
                Dim d As Division
    
                Me.LeaguesDataSource.Add(InlineAssignHelper(l, New League("League A")))
                l.Divisions.Add((InlineAssignHelper(d, New Division("Division A"))))
                d.Teams.Add(New Team("Team I"))
                d.Teams.Add(New Team("Team II"))
                d.Teams.Add(New Team("Team III"))
                d.Teams.Add(New Team("Team IV"))
                d.Teams.Add(New Team("Team V"))
                l.Divisions.Add((InlineAssignHelper(d, New Division("Division B"))))
                d.Teams.Add(New Team("Team Blue"))
                d.Teams.Add(New Team("Team Red"))
                d.Teams.Add(New Team("Team Yellow"))
                d.Teams.Add(New Team("Team Green"))
                d.Teams.Add(New Team("Team Orange"))
                l.Divisions.Add((InlineAssignHelper(d, New Division("Division C"))))
                d.Teams.Add(New Team("Team East"))
                d.Teams.Add(New Team("Team West"))
                d.Teams.Add(New Team("Team North"))
                d.Teams.Add(New Team("Team South"))
                Me.LeaguesDataSource.Add(InlineAssignHelper(l, New League("League B")))
                l.Divisions.Add((InlineAssignHelper(d, New Division("Division A"))))
                d.Teams.Add(New Team("Team 1"))
                d.Teams.Add(New Team("Team 2"))
                d.Teams.Add(New Team("Team 3"))
                d.Teams.Add(New Team("Team 4"))
                d.Teams.Add(New Team("Team 5"))
                l.Divisions.Add((InlineAssignHelper(d, New Division("Division B"))))
                d.Teams.Add(New Team("Team Diamond"))
                d.Teams.Add(New Team("Team Heart"))
                d.Teams.Add(New Team("Team Club"))
                d.Teams.Add(New Team("Team Spade"))
                l.Divisions.Add((InlineAssignHelper(d, New Division("Division C"))))
                d.Teams.Add(New Team("Team Alpha"))
                d.Teams.Add(New Team("Team Beta"))
                d.Teams.Add(New Team("Team Gamma"))
                d.Teams.Add(New Team("Team Delta"))
                d.Teams.Add(New Team("Team Epsilon"))
            End Sub
            Private Shared Function InlineAssignHelper(Of T)(ByRef target As T, ByVal value As T) As T
                target = value
                Return value
            End Function
        End Class
    
  • The next step is to declare the RadTreeViewSampleData as a resource in your application.

        <UserControl.Resources>
            <sampleData:RadTreeViewSampleData x:Key="DataSource"/>
        </UserControl.Resources>
    

    The sampleData alias points to the assembly where your data source is located.

  • Since the data is hierarchical, you need to declare a HierarchicalDataTemplate. If you want to learn about the hierarchical data template, read the topic about Hierarchical Data Templates.

        <UserControl.Resources>
            <sampleData:RadTreeViewSampleData x:Key="DataSource"/>
    
            <DataTemplate x:Key="Team">
                <TextBlock Text="{Binding Name}" />
            </DataTemplate>    
            <telerik:HierarchicalDataTemplate x:Key="Division" ItemTemplate="{StaticResource Team}"
                   ItemsSource="{Binding Teams}">
                <TextBlock Text="{Binding Name}" />
            </telerik:HierarchicalDataTemplate>
            <telerik:HierarchicalDataTemplate x:Key="League" ItemTemplate="{StaticResource Division}"
                   ItemsSource="{Binding Divisions}">
                <TextBlock Text="{Binding Name}" />
            </telerik:HierarchicalDataTemplate>
        </UserControl.Resources>
    
  • Finally, here is the treeview declaration. For ItemsSource is used the DataSource resource. For ItemTemplate is set the created in the previous step hierarchical data template.

        <telerik:RadTreeView
               ItemsSource="{Binding Source={StaticResource DataSource}, Path=LeaguesDataSource}"
               ItemTemplate="{StaticResource League}" />
    
  • If you run the demo, the final result should look like the snapshot below.

See Also