ObservableProperty failed in release mode

[rodolfo-sousa]

Describe the bug

I start to have a problem with the last version of CommunityToolkit.Mvvm 8.4.0 (I tried 8.3.2 too), where it fails to change an Observable Property when using RelativeSource AncestorType on Release mode.

So, I have a user control that appears every time the MessageShow changed to True in ViewModel. After click on a button inside of the control, the same property is changed to False.
Every time I need to show the control a do the same.

It stop to work after I update Toolkit and SDKs.

Here is a sample, works in Debug but fails in Release mode:

        <controls:CPopUps   BindingContext="{Binding Source={RelativeSource AncestorType={x:Type viewmodels:DebugViewModel}}}"
                                                      
                            MessageShow="{Binding PopUpMessageShow, Source={RelativeSource AncestorType={x:Type viewmodels:DebugViewModel}}, Mode=OneWay}" />

I tried to disable AOT and Trimmed but no luck.

So I found this approach and it worked:

        <controls:CPopUps   BindingContext="{Binding Source={RelativeSource AncestorType={x:Type viewmodels:DebugViewModel}}}"
                                                      
                            MessageShow="{Binding PopUpMessageShow, Mode=OneWay}" />

Don't know if a BUG or bad usage, but was working in the past...

Regression

SDK 9.0.202

Steps to reproduce

1. Create a user control with Binding properties;
2. Put it on a View;
3. Change the property from ViewModel;
4. Change the property in User Control;
5. Property is not changed on ViewModel;

Expected behavior

Observable Property should be updated on ViewModel after it's changed in the user control.

Screenshots

No response

IDE and version

VS 2022

IDE version

17.14.9

Nuget packages

• CommunityToolkit.Common
• CommunityToolkit.Diagnostics
• CommunityToolkit.HighPerformance
• CommunityToolkit.Mvvm (aka MVVM Toolkit)

Nuget package version(s)

8.4.0

Additional context

No response

Help us help you

No, just wanted to report this