public class ReadOnlyDependencyPropertyBindingBehavior :
    Behavior<DependencyObject>

Public Class ReadOnlyDependencyPropertyBindingBehavior
    Inherits Behavior(Of DependencyObject)

<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>

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

<dx:ThemedWindow x:Class="DXSample.MainWindow"
                 Title="{DXBinding '`GridControl has errors: ` + HasErrors'}">

    <dx:ThemedWindow.DataContext>
        <local:MainViewModel />
    </dx:ThemedWindow.DataContext>

    <DockPanel>
        <dxg:GridControl AutoGenerateColumns="AddNew"
                         ItemsSource="{Binding TaskList}">
            <dxg:GridControl.View>
                <dxg:TableView ErrorsWatchMode="Cells"
                               InvalidRowExceptionCommand="{Binding InvalidRowCommand}"
                               ValidateRowCommand="{Binding ValidateRowCommand}">
                    <dxmvvm:Interaction.Behaviors>
                        <dxmvvm:ReadOnlyDependencyPropertyBindingBehavior Property="HasErrors"
                                                                          Binding="{Binding HasErrors, UpdateSourceTrigger=PropertyChanged}" />
                    </dxmvvm:Interaction.Behaviors>
                </dxg:TableView>
            </dxg:GridControl.View>
        </dxg:GridControl>
    </DockPanel>

</dx:ThemedWindow>

public class MainViewModel : ViewModelBase {
    public bool HasErrors {
        get { return GetValue<bool>(); }
        set { SetValue(value); }
    }
    public ObservableCollection<Task> TaskList { get; }
    public MainViewModel() {
        TaskList = new ObservableCollection<Task> {
            new Task() {
                TaskName = "Complete Project A",
                StartDate = new DateTime(2009, 7, 17),
                EndDate = new DateTime(2009, 7, 10)
            },
            new Task() {
                TaskName = "Test Website",
                StartDate = new DateTime(2009, 7, 10),
                EndDate = new DateTime(2009, 7, 12)
            },
            new Task() {
                TaskName = string.Empty,
                StartDate = new DateTime(2009, 7, 4),
                EndDate = new DateTime(2009, 7, 6)
            }
        };
    }

    [Command]
    public void ValidateRow(RowValidationArgs args) {
        args.Result = GetValidationErrorInfo((Task)args.Item);
    }
    static ValidationErrorInfo GetValidationErrorInfo(Task task) {
        if (task.StartDate > task.EndDate)
            return new ValidationErrorInfo("Start Date must be less than End Date");
        if (string.IsNullOrEmpty(task.TaskName))
            return new ValidationErrorInfo("Enter a task name");
        return null;
    }

    [Command]
    public void InvalidRow(InvalidRowExceptionArgs args) {
        args.ExceptionMode = ExceptionMode.NoAction;
    }
}

Public Class MainViewModel
    Inherits ViewModelBase

    Public Property HasErrors As Boolean
        Get
            Return GetValue(Of Boolean)()
        End Get

        Set(ByVal value As Boolean)
            SetValue(value)
        End Set
    End Property

    Public ReadOnly Property TaskList As ObservableCollection(Of Task)

    Public Sub New()
        TaskList = New ObservableCollection(Of Task) From {New Task() With {.TaskName = "Complete Project A", .StartDate = New DateTime(2009, 7, 17), .EndDate = New DateTime(2009, 7, 10)}, New Task() With {.TaskName = "Test Website", .StartDate = New DateTime(2009, 7, 10), .EndDate = New DateTime(2009, 7, 12)}, New Task() With {.TaskName = String.Empty, .StartDate = New DateTime(2009, 7, 4), .EndDate = New DateTime(2009, 7, 6)}}
    End Sub

    <Command>
    Public Sub ValidateRow(ByVal args As RowValidationArgs)
        args.Result = GetValidationErrorInfo(CType(args.Item, Task))
    End Sub

    Private Shared Function GetValidationErrorInfo(ByVal task As Task) As ValidationErrorInfo
        If task.StartDate > task.EndDate Then Return New ValidationErrorInfo("Start Date must be less than End Date")
        If String.IsNullOrEmpty(task.TaskName) Then Return New ValidationErrorInfo("Enter a task name")
        Return Nothing
    End Function

    <Command>
    Public Sub InvalidRow(ByVal args As InvalidRowExceptionArgs)
        args.ExceptionMode = ExceptionMode.NoAction
    End Sub
End Class