ReadOnlyDependencyPropertyBindingBehavior Class

Allows you to bind read-only dependency and attached properties to a ViewModel’s properties.

Assembly: DevExpress.Xpf.Core.v21.1.dll

Declaration

C#
VB.NET

public class ReadOnlyDependencyPropertyBindingBehavior :
    Behavior<DependencyObject>

Public Class ReadOnlyDependencyPropertyBindingBehavior
    Inherits Behavior(Of DependencyObject)

Remarks

The following properties are required to use ReadOnlyDependencyPropertyBindingBehavior:

Property	Description
Binding	Gets or sets a binding that should be applied to the specified property. This is a dependency property.
Property or DependencyProperty	Gets or sets the bound property. This is a dependency property.

The following table lists additional customization properties:

Property	Description
Command	Gets or sets the command that the ReadOnlyDependencyPropertyBindingBehavior should execute when the bound property’s value is changed (specified in the Property or DependencyProperty). This is a dependency property.
IsEnabled	Gets or sets whether a bound ViewModel’s property should be updated. This is a dependency property.

Follow the steps below to bind a read-only dependency property to a ViewModel’s property:

Attach the behavior to a target control and choose one of the following options:

Set the Property to a target property’s name:

XAML

 <TreeView>
     <dxmvvm:Interaction.Behaviors>
         <dxmvvm:ReadOnlyDependencyPropertyBindingBehavior Property="SelectedItem" />
     </dxmvvm:Interaction.Behaviors>
 </TreeView>

Use the DependencyProperty to specify a target dependency/attached property:

XAML

 <TreeView>
    <dxmvvm:Interaction.Behaviors>
        <dxmvvm:ReadOnlyDependencyPropertyBindingBehavior DependencyProperty="{x:Static TreeView.SelectedItemProperty}" />
    </dxmvvm:Interaction.Behaviors>
 </TreeView>

Use the behavior’s Binding property to specify a binding to the target ViewModel’s property.

XAML

<TreeView>
    <dxmvvm:Interaction.Behaviors>
        <dxmvvm:ReadOnlyDependencyPropertyBindingBehavior Binding="{Binding SelectedMenuItem, Mode=OneWayToSource}"
                                                          DependencyProperty="{x:Static TreeView.SelectedItemProperty}" />
    </dxmvvm:Interaction.Behaviors>
</TreeView>

The following code sample binds the TreeView.SelectedItem read-only property to the ViewModel’s SelectedMenuItem property:

MainView.xaml

<UserControl x:Class="DXSample.Views.MainView"
<!-- ... -->
             xmlns:dxmvvm="http://schemas.devexpress.com/winfx/2008/xaml/mvvm"
             <!-- ... -->
             xmlns:ViewModels="clr-namespace:DXSample.ViewModels"
             <!-- ... -->
    <UserControl.DataContext>
        <ViewModels:MainViewModel />
    </UserControl.DataContext>

    <DockPanel>
        <TreeView Name="view" ItemsSource="{Binding Menu}">
            <TreeView.Resources>
                <HierarchicalDataTemplate DataType="{x:Type ViewModels:MenuItemViewModel}" ItemsSource="{Binding Items}">
                    <TextBlock Text="{Binding Title}" />
                </HierarchicalDataTemplate>
            </TreeView.Resources>
            <dxmvvm:Interaction.Behaviors>
                <dxmvvm:ReadOnlyDependencyPropertyBindingBehavior Binding="{Binding SelectedMenuItem, Mode=OneWayToSource}"
                                                                  DependencyProperty="{x:Static TreeView.SelectedItemProperty}" />
            </dxmvvm:Interaction.Behaviors>
        </TreeView>
    </DockPanel>

</UserControl>

MainViewModel.cs
MainViewModel.vb

using System.Collections.ObjectModel;
using System.Windows;
using DevExpress.Mvvm;
using DevExpress.Mvvm.DataAnnotations;
// ...
    public class MainViewModel : ViewModelBase {
        public MenuItemViewModel SelectedMenuItem {
            get { return GetProperty(() => SelectedMenuItem); }
            set { SetProperty(() => SelectedMenuItem, value); }
        }

        [Command]
        public void Open() {
        // ...
        }
        // ...
    }

Imports System.Collections.ObjectModel
Imports System.Windows
Imports DevExpress.Mvvm
Imports DevExpress.Mvvm.DataAnnotations
' ...
    Public Class MainViewModel
        Inherits ViewModelBase

        Public Property SelectedMenuItem As MenuItemViewModel
            Get
                Return GetProperty(Function() Me.SelectedMenuItem)
            End Get

            Set(ByVal value As MenuItemViewModel)
                SetProperty(Function() SelectedMenuItem, value)
            End Set
        End Property

        <Command>
        Public Sub Open()
        ' ...
        End Sub
        ' ...
    End Class

View Example