ViewModelBase Class

The BindableBase descendant that implements the ISupportUIServices interface and allows you to access UI Services registered within a View.

Namespace: DevExpress.Mvvm

Assembly: DevExpress.WinUI.Mvvm.v23.2.dll

NuGet Package: DevExpress.WinUI

Declaration

C#

public abstract class ViewModelBase :
    BindableBase,
    ISupportUIServices

VB.NET

Public MustInherit Class ViewModelBase
    Inherits BindableBase
    Implements ISupportUIServices

Remarks

Run Demo: ViewModelBase Module in the WinUI MVVM Demo

The ViewModel class implements the ISupportUIServices interface and allows you to access UI Services defined in the view.

The following code sample gets an IMessageBoxService instance that is defined in the view:

XAML

<UserControl ...
    xmlns:dx="using:DevExpress.WinUI.Core"
    xmlns:ViewModel="using:WinUIApp.ViewModels"> 
    <UserControl.DataContext>
        <ViewModel:ViewModel/>
    </UserControl.DataContext>
    <dx:Interaction.Behaviors>
        <dx:MessageBoxService/>
    </dx:Interaction.Behaviors>

    <!-- Registers a service into a specified ViewModel: -->
    <dx:Interaction.Behaviors>
        <dx:MessageBoxService ServiceClient="{x:Bind ViewModel}"/>
    </dx:Interaction.Behaviors>
</UserControl>

C#

public class ViewModel : ViewModelBase {
    public IMessageBoxService MessageBoxService => GetUIService<IMessageBoxService>();
}

VB.NET

Public Class ViewModel
    Inherits ViewModelBase
    Public ReadOnly Property MessageBoxService As IMessageBoxService
        Get
            Return GetUIService(Of IMessageBoxService)()
        End Get
    End Property
End Class

In the code sample above, the UIServiceBase.ServiceClient property specifies the ViewModel where the service is registered.

Implements

ISupportUIServices

Inheritance

Object

BindableBase

ViewModelBase