(MAUI) It's hard to know if an event made an app crash

[lucas-zimerman]

https://sentry.lkp.app.br/share/issue/6a79ea41e23348e9ad9680c4887ca800/

System.InvalidOperationException: PlatformView cannot be null here
  ?, in UIImageView ViewHandler<IImage, UIImageView>.get_PlatformView()
  ?, in UIImageView ImageHandler.Microsoft.Maui.Handlers.IImageHandler.get_PlatformView()
  ?, in void ImageImageSourcePartSetter.SetImageSource(UIImage platformImage)
  ?, in async Task<IImageSourceServiceResult<UIImage>> ImageSourcePartExtensions.UpdateSourceAsync(IImageSourcePart image, UIView destinationContext, IImageSourceServiceProvider services, Action<UIImage> setImage, float imageScale, CancellationToken cancellationToken)
  ?, in async Task ImageSourcePartLoader.UpdateImageSourceAsync()
  ?, in async Task ImageHandler.MapSourceAsync(IImageHandler handler, IImage image)
  ?, in async void TaskExtensions.FireAndForget(Task task, Action<Exception> errorCallback)

This issue is marked as unhandled, but the trace shows user used the app after the unhandled exception (all those stacktraces came from the Maui Assembly)

With that said, it's hard to know when an app actually crashed due to an event, that is helpful information to prioritize issues.

[jamescrosswell]

@lucas-zimerman on iOS we can't use the UnhandledException callback so we use the RuntimeMarshalManagedException callback instead (see #3909).

One of the downsides of this is that the arguments to RuntimeMarshalManagedException don't indicate whether the exception is terminal or not.

We're hoping the root cause gets addressed in .NET 10:

• See if we can replace with UnhandledException handler #4180

[lucas-zimerman]

would it be possible to mark the issues as unhandled, and after a period of time (lets say 5 seconds) if the code is still functional then mark it again as handled?

[jamescrosswell]

would it be possible to mark the issues as unhandled, and after a period of time (lets say 5 seconds) if the code is still functional then mark it again as handled?

I don't think so no. In the case that the event does lead to an app crash, we want to try to capture the event as soon as possible. Since we don't know whether the exception is terminal or not, there's no way to work out whether we should send the event immediately or hold it in purgatory.