Changing host WinForm properties from ViewModel bound to ElementHost - wpf

Question

Can anyone suggest approaches that will allow me to change the properties of a host WinForm from a WPF element in an ElementHost?
I have an MVVM application using Prism that's bound to an ElementHost. I would like to change the WinForm title, resize the WinForm and close the WinForm from within my ViewModel.
I understand receiving data from a WPF composite control described in this article but I can't see how that will work in a ViewModel.
App is the WinForm
ChartWizardViewModel is the ViewModel I want to change the properties of App from.
Everything else is the Prism architecture. Shell, Bootstrapper etc.
Public Class App
Public Sub New(ByVal modulesToLoad As List(Of String))
' This call is required by the designer.
InitializeComponent()
If Application.Current Is Nothing Then
Dim wpfAppAdapter As New WpfApplicationAdapter
End If
' Load the application modules
Dim formBootstrapper As New Bootstrapper(modulesToLoad)
formBootstrapper.Run()
' Get the current instance of shell and bind it to the ElementHost
Dim shellElement = formBootstrapper.Container.Resolve(Of Shell)()
ehMaster.Child = shellElement
End Sub
End Class
Public NotInheritable Class Bootstrapper
Inherits UnityBootstrapper
Private _modulesToLoad As List(Of String) ' The modules that we want to load
Public Sub New(ByVal modulesToLoad As List(Of String))
_modulesToLoad = modulesToLoad
End Sub
Protected Overrides Function CreateShell() As DependencyObject
Dim shell = Container.Resolve(Of Shell)()
Return shell
End Function
Protected Overrides Function GetModuleCatalog() As IModuleCatalog
Dim catalog As ModuleCatalog = New ConfigurationModuleCatalog()
For Each moduleToLoad As String In _modulesToLoad
Select Case StringHelper.CleanString(moduleToLoad)
Case "chartwizardmodule"
catalog.AddModule(GetType(ChartWizardModule))
End Select
Next
Return catalog
End Function
End Class
Public NotInheritable Class ChartWizardModule
Implements IModule
Private ReadOnly regionManager As IRegionManager
Public Sub Initialize() Implements IModule.Initialize
regionManager.RegisterViewWithRegion("MainRegion", GetType(MainWindow))
End Sub
Public Sub New(regionManager As IRegionManager)
Me.regionManager = regionManager
End Sub
End Class
Partial Public Class MainWindow
Private _objChartWizardViewModel As ChartWizardViewModel ' The chart wizard base view model that controls the rest of the views
Private Sub MainWindow_Loaded(ByVal sender As Object, ByVal e As System.Windows.RoutedEventArgs) Handles Me.Loaded
Dim objChartWizardViewModel As New ChartWizardViewModel()
_objChartWizardViewModel = objChartWizardViewModel
' Data Context for the Chart Wizard
Me.DataContext = _objChartWizardViewModel
End Sub
End Class
Public Class ChartWizardViewModel
Implements INotifyPropertyChanged
' I need to change the properties of the WinForm (App) from here
End Class

Answer 1

I solved this with an EventAggregator as discussed in this post
Using EventAggregator to communicate between WPF in ElementHost and host WinForm