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TabControl.ContentTemplateSelector Property

Definition

Gets or sets a DataTemplateSelector that provides custom logic for choosing the template that is used to display the content of the control.

public:
 property System::Windows::Controls::DataTemplateSelector ^ ContentTemplateSelector { System::Windows::Controls::DataTemplateSelector ^ get(); void set(System::Windows::Controls::DataTemplateSelector ^ value); };
public System.Windows.Controls.DataTemplateSelector ContentTemplateSelector { get; set; }
member this.ContentTemplateSelector : System.Windows.Controls.DataTemplateSelector with get, set
Public Property ContentTemplateSelector As DataTemplateSelector

Property Value

A ContentTemplateSelector. The default is null.

Examples

The following example uses the ContentTemplateSelector property to display the content of a TabItem differently, depending on the hometown of the selected person.

<DataTemplate x:Key="DetailTemplate">
  <Border Width="300" Height="100" Margin="20"
          BorderBrush="Aqua" BorderThickness="1" Padding="8">
    <Grid>
      <Grid.RowDefinitions>
        <RowDefinition/>
        <RowDefinition/>
        <RowDefinition/>
      </Grid.RowDefinitions>
      <Grid.ColumnDefinitions>
        <ColumnDefinition Width="100"/>
        <ColumnDefinition/>
      </Grid.ColumnDefinitions>
      <TextBlock Grid.Row="0" Grid.Column="0" Text="First Name:"/>
      <TextBlock Grid.Row="0" Grid.Column="1" Text="{Binding Path=FirstName}"/>
      <TextBlock Grid.Row="1" Grid.Column="0" Text="Last Name:"/>
      <TextBlock Grid.Row="1" Grid.Column="1" Text="{Binding Path=LastName}"/>
      <TextBlock Grid.Row="2" Grid.Column="0" Text="Home Town:"/>
      <TextBox Grid.Row="2" Grid.Column="1" Text="{Binding Path=HomeTown}"/>
    </Grid>
  </Border>
</DataTemplate>

<DataTemplate x:Key="SeattleTemplate">
  <DataTemplate.Resources>
    <Style TargetType="TextBlock">
      <Setter Property="FontSize" Value="16"/>
    </Style>
  </DataTemplate.Resources>
  <Border Width="300" Height="100" Margin="20"
          BorderBrush="DarkSeaGreen" BorderThickness="3" Padding="15">
    <Grid>
      <Grid.RowDefinitions>
        <RowDefinition/>
        <RowDefinition/>
        <RowDefinition/>
      </Grid.RowDefinitions>
      <Grid.ColumnDefinitions>
        <ColumnDefinition Width="120"/>
        <ColumnDefinition/>
      </Grid.ColumnDefinitions>
      <TextBlock Grid.Row="0" Grid.Column="0" Text="Please welcome"/>
      <DockPanel Grid.Row="0" Grid.Column="1" >
        <TextBlock Text="{Binding Path=FirstName}"/>
        <TextBlock Text=" "/>
        <TextBlock Text="{Binding Path=LastName}"/>
      </DockPanel>
      <TextBlock Grid.Row="1" Grid.ColumnSpan="2" Text="from the Emerald City!"/>
    </Grid>
  </Border>
</DataTemplate>
<!--Bind to the collection MyFriends and use a DataTemplateSelector
to specify the appearance of the content.-->
<TabControl Name="tabCtrl1" Width="400" Height="200" 
         ItemsSource="{Binding Source={StaticResource MyFriends}}"
         ContentTemplateSelector="{StaticResource PersonSelector}"/>
using System;
using System.Collections.Generic;
using System.Text;
using System.Collections.ObjectModel;
using System.ComponentModel;

namespace TabControlContentTemplateSelector
{
    // Create a class that represents a person.  
    // This class contains a person's first name, last name, 
    // and hometown.
    public class Person : INotifyPropertyChanged
    {
        private string firstname;
        private string lastname;
        private string hometown;

        public event PropertyChangedEventHandler PropertyChanged;

        public Person()
        {
        }

        public Person(string first, string last, string town)
        {
            this.firstname = first;
            this.lastname = last;
            this.hometown = town;
        }

        public override string ToString()
        {
            return firstname.ToString();
        }

        public string FirstName
        {
            get { return firstname; }
            set
            {
                firstname = value;
                OnPropertyChanged("FirstName");
            }
        }

        public string LastName
        {
            get { return lastname; }
            set
            {
                lastname = value;
                OnPropertyChanged("LastName");
            }
        }

        public string HomeTown
        {
            get { return hometown; }
            set
            {
                hometown = value;
                OnPropertyChanged("HomeTown");
            }
        }

        protected void OnPropertyChanged(string info)
        {
            PropertyChangedEventHandler handler = PropertyChanged;
            if (handler != null)
            {
                handler(this, new PropertyChangedEventArgs(info));
            }
        }
    }
public class PersonTemplateSelector : DataTemplateSelector
{
    public override DataTemplate SelectTemplate(object item, DependencyObject container)
    {

        // The content of each TabItem is a Person object.
        if (item is Person)
        {
            Person person = item as Person;

            Window win = Application.Current.MainWindow;

            // Select one of the DataTemplate objects, based on the 
            // person's home town.
            if (person.HomeTown == "Seattle")
            {
                return win.FindResource("SeattleTemplate") as DataTemplate;
            }
            else
            {
                return win.FindResource("DetailTemplate") as DataTemplate;
            }
        }

        return null;
    }
}
Imports System.ComponentModel

Public Class Person
    Implements INotifyPropertyChanged

    ' Events
    Public Event PropertyChanged As PropertyChangedEventHandler Implements INotifyPropertyChanged.PropertyChanged

    ' Methods
    Public Sub New()
    End Sub

    Public Sub New(ByVal first As String, ByVal last As String, ByVal town As String)
        Me._firstname = first
        Me._lastname = last
        Me._hometown = town
    End Sub

    Private Sub OnPropertyChanged(ByVal info As String)
        RaiseEvent PropertyChanged(Me, New PropertyChangedEventArgs(info))
    End Sub

    Public Overrides Function ToString() As String
        Return Me._firstname.ToString
    End Function


    ' Properties
    Public Property FirstName() As String
        Get
            Return Me._firstname
        End Get
        Set(ByVal value As String)
            Me._firstname = value
            Me.OnPropertyChanged("FirstName")
        End Set
    End Property

    Public Property HomeTown() As String
        Get
            Return Me._hometown
        End Get
        Set(ByVal value As String)
            Me._hometown = value
            Me.OnPropertyChanged("HomeTown")
        End Set
    End Property

    Public Property LastName() As String
        Get
            Return Me._lastname
        End Get
        Set(ByVal value As String)
            Me._lastname = value
            Me.OnPropertyChanged("LastName")
        End Set
    End Property


    ' Fields
    Private _firstname As String
    Private _hometown As String
    Private _lastname As String
End Class
Public Class PersonTemplateSelector
    Inherits DataTemplateSelector

    Public Overrides Function SelectTemplate(ByVal item As Object, _
                     ByVal container As DependencyObject) As DataTemplate

        ' The content of each TabItem is a Person object.
        If TypeOf item Is Person Then

            Dim person As Person = item

            Dim win As Window = Application.Current.MainWindow

            ' Select one of the DataTemplate objects, based on the 
            ' person's home town.
            If person.HomeTown = "Seattle" Then
                Return win.FindResource("SeattleTemplate")
            Else
                Return win.FindResource("DetailTemplate")

            End If
        End If

        Return Nothing
    End Function

End Class

Remarks

Typically, you create a DataTemplateSelector when you have more than one DataTemplate for the same type of objects and you want to supply your own logic to choose a DataTemplate to apply based on the properties of each data object. Note that if you have objects of different types, you can set the DataType property on the DataTemplate. If you do that, then there is no need to create a DataTemplateSelector. Furthermore, if you have objects of the same type but with different properties, you can also consider using a DataTrigger or a data converter. For more information, see Data Templating Overview.

To create a template selector, create a class that inherits from DataTemplateSelector and override the SelectTemplate method. After your class is defined, you can assign an instance of the class to the template selector property of your element.

If both the ContentTemplateSelector and the ContentTemplate properties are set, then this property is ignored.

XAML Attribute Usage

<object ContentTemplateSelector="{ResourceExtension DataTemplateSelectorClassKey}"/>  

XAML Property Element Usage

<object>  
  <object.ContentTemplateSelector>  
    <MyDataTemplateSelectorImplementation .../>  
  </object.ContentTemplateSelector>  
</object>  

XAML Values

ResourceExtension
One of the following: StaticResource, or DynamicResource. See XAML Resources.

DataTemplateSelectorClassKey
The key that identifies the selector implementation being requested. The key refers to a derived class that implements a practical SelectTemplate override. For information about how to map your custom class, see XAML Namespaces and Namespace Mapping for WPF XAML. You can also programmatically add an instance of your DataTemplateSelector class as a resource to a resource dictionary.

MyDataTemplateSelectorImplementation
A class derived from DataTemplateSelector and overrides SelectTemplate. For information about how to map your custom class, see XAML Namespaces and Namespace Mapping for WPF XAML.

Dependency Property Information

Identifier field ContentTemplateSelectorProperty
Metadata properties set to true None

Applies to