Getting Exception While Subscribing TextBox LosingFocus Event UWP XAMl - xaml

Question

I am Dynamically creating a TextBox Control and I have Subscribed the TextBox LosingFocus Event and Its working fine on Local Machine but it is giving exception on Virtual Machine.
Getting the Following Error:
Unable to cast object of type 'Windows.UI.Xaml.Controls.TextBox' to
type 'Windows.UI.Xaml.IUIElement5
and The Stacktrace is:
at System.StubHelpers.StubHelpers.GetCOMIPFromRCW_WinRT(Object objSrc, IntPtr pCPCMD,
IntPtr& ppTarget) at
Windows.UI.Xaml.UIElement.add_LosingFocus(TypedEventHandler`2 value) at
System.Runtime.InteropServices.WindowsRuntime.WindowsRuntimeMarshal.NativeOrStaticEventRegistrationImpl.AddEventHandler[T](Func`2
addMethod, Action`1 removeMethod, T handler)
at
System.Runtime.InteropServices.WindowsRuntime.WindowsRuntimeMarshal.AddEventHandler[T](Func`2
addMethod, Action`1 removeMethod, T handler)
_XamlTypeInfo.XamlUserType.ActivateInstance()
Please Help me To Solve That Issue.
Thanks.

Answer 1

The LosingEvent has been introduced in the Windows API contract V4 (Windows build 15063+).
It is not available on the Windows build you are using in your VM (14393).
You can see the minimal OS/API contract version in the LosingEvent documentation
Additional features and requirements
Device family : Windows 10 Creators Update (introduced v10.0.15063.0)
API contract : Windows.Foundation.UniversalApiContract (introduced v4)
Since you're minimal target is Windows build 10240 (API contract V1), you need to perform a runtime check before registering to this event.
if (ApiInformation.IsApiContractPresent("Windows.Foundation.UniversalApiContract"), 4, 0)
{
// This device supports all APIs in UniversalApiContract version 4.0
}
This is the only way to validate if the API is available. You will have a detailed explanation about how to target multiple Windows version here
If the event is absolutly mandatory for what you want to do, you will need to upgrade the minimum target platform to 15063. By doing this, your application will no longer be able to run on older OS builds.