Proper way to throw error in OnNavigatedTo?

[znakeeye]

In a WPF app, when navigation fails you can get hold of the error in the navigation callback. However, I want the app to crash when a certain critical error occurs. What is the proper way to accomplish this? Re-throwing the error merely prints it in the Output Window. I cannot see where it is being caught.

regionManager.RequestNavigate(regionName, targetView.Name, OnNavigationResult, parameters);

private void OnNavigationResult(NavigationResult result)
{
    if (result.Error != null)
    {
        throw result.Error; // Will just print to Output Window.
    }
}

Output Window

 ---> DryIoc.ContainerException: code: Error.UnableToResolveFromRegisteredServices;
message: Unable to resolve resolution root Foo.MyViewModel
  from container without scope
 with Rules with {TrackingDisposableTransients, UseDynamicRegistrationsAsFallbackOnly, FuncAndLazyWithoutRegistration, SelectLastRegisteredFactory} and without {ThrowOnRegisteringDisposableTransient, UseFastExpressionCompilerIfPlatformSupported}
 with FactorySelector=SelectLastRegisteredFactory
 with Made={FactoryMethod=ConstructorWithResolvableArguments}
  with normal and dynamic registrations:
  (DefaultDynamicKey(0), {FactoryID=251, ImplType=Foo.MyViewModel, Reuse=TransientReuse, HasCondition})
   at DryIoc.Throw.It(Int32 error, Object arg0, Object arg1, Object arg2, Object arg3) in /_/src/DryIoc/Container.cs:line 13773
   at DryIoc.Container.TryThrowUnableToResolve(Request request) in /_/src/DryIoc/Container.cs:line 1088
   at DryIoc.Container.DryIoc.IContainer.ResolveFactory(Request request) in /_/src/DryIoc/Container.cs:line 1070
   at DryIoc.Container.ResolveAndCache(Int32 serviceTypeHash, Type serviceType, IfUnresolved ifUnresolved) in /_/src/DryIoc/Container.cs:line 371
   at DryIoc.Container.DryIoc.IResolver.Resolve(Type serviceType, IfUnresolved ifUnresolved) in /_/src/DryIoc/Container.cs:line 360
   at Prism.DryIoc.DryIocContainerExtension.Resolve(Type type, ValueTuple`2[] parameters)
   --- End of inner exception stack trace ---
   at Foo.ViewManager.OnNavigationResult(NavigationResult result) in C:\Foo\ViewManager.cs:line 71
   at Prism.Regions.RegionNavigationService.NotifyNavigationFailed(NavigationContext navigationContext, Action`1 navigationCallback, Exception e)
   at Prism.Regions.RegionNavigationService.RequestNavigate(Uri target, Action`1 navigationCallback, NavigationParameters navigationParameters)
   at Prism.Regions.Region.RequestNavigate(Uri target, Action`1 navigationCallback, NavigationParameters navigationParameters)
   at Prism.Regions.RegionManager.RequestNavigate(String regionName, Uri target, Action`1 navigationCallback, NavigationParameters navigationParameters)

[brianlagunas]

It could be something specific about where you are calling it (Maybe in an async/void) or your debug settings in VS. It crashes for me.

[znakeeye]

Here's a sample demonstrating the silent exception. Maybe related to auto-wiring of the viewmodel?

PrismNoCrashDemo.zip

[brianlagunas]

Your sample is different from your code snippet above. Handling the navigation result and rethrowing works as expected

            regionManager.RequestNavigate("MainRegion", nameof(MainView), result =>
            {
                if (result.Error != null)
                {
                    throw result.Error;
                }
            });

[znakeeye]

Ok, getting closer. Maybe this is a generic WPF "problem" I'm seeing? When issuing the navigation from within a bound property setter, the exception is swallowed.

PrismExceptionFromSetterDemo.zip

[znakeeye]

I guess I must dispatch the operation when inside a bound property. This seems to work:

SynchronizationContext.Current.Post(d =>
{
    regionManager.RequestNavigate("MainRegion", "MainView", OnNavigationCallback);
}, null);