Unhandled Xamarin Android exceptions have bad stack trace when logging to Visual Studio App Center

Question

I'm implementing Visual Studio AppCenter for handling crashes, as it's replacing HockeyApp. I'm testing it out by throwing an exception manually in my code (NOT within a try/catch block):

throw new Exception ("New exception when redirecting to property details!");

I then have code that globally handles any uncaught exceptions in Application.cs and tries to log them to AppCenter with the Crashes.TrackError call:

AndroidEnvironment.UnhandledExceptionRaiser += LogException;

private void LogException (object sender, RaiseThrowableEventArgs e) {
            var exc = e.Exception;
            if (ShouldLogException (exc)) {
                // Log exception to AppCenter.
                var properties = AppCenterLoggingSink.GetProperties ();
                Crashes.TrackError (exc, properties);
                e.Handled = true;
            }
        }

When I do this, the stack trace that it logs to the console looks good:

[MonoDroid] System.Exception: New exception when redirecting to property details! [MonoDroid] at RPR.Mobile.Droid.Fragments.RecentActivityFragment.RedirectToPropertyDetails (RPR.Mobile.Shared.Entities.PropertyDetails.Property property) [0x00001] in /Users/justintoth/Documents/rpr-mobile/android-application/Fragments/RecentActivityFragment.cs:190 [MonoDroid] at RPR.Mobile.Droid.Fragments.RecentActivityFragment.b__15_0 (RPR.Mobile.Shared.Entities.PropertyDetails.Property property) [0x00000] in /Users/justintoth/Documents/rpr-mobile/android-application/Fragments/RecentActivityFragment.cs:170 [MonoDroid] at RPR.Mobile.Droid.Adapters.SearchResults.PropertyListRowPhotoAdapter.b__2_0 (System.Object o, System.EventArgs e) [0x00001] in /Users/justintoth/Documents/rpr-mobile/android-application/Adapters/SearchResults/PropertyListRowPhotoAdapter.cs:34 [MonoDroid] at Android.Views.View+IOnClickListenerImplementor.OnClick (Android.Views.View v) [0x00011] in <5f142c269d8a438c94480ac03744dec7>:0 [MonoDroid] at Android.Views.View+IOnClickListenerInvoker.n_OnClick_Landroid_view_View_ (System.IntPtr jnienv, System.IntPtr native__this, System.IntPtr native_v) [0x00011] in <5f142c269d8a438c94480ac03744dec7>:0 [MonoDroid] at (wrapper dynamic-method) System.Object.60(intptr,intptr,intptr)

However, as the app closes it logs the exception to the console with a bad stack trace:

[AppCenterCrashes] System.Exception: New exception when redirecting to property details! [AppCenterCrashes] at (wrapper dynamic-method) System.Object.60(intptr,intptr,intptr) [AppCenterCrashes] at (wrapper native-to-managed) System.Object.60(intptr,intptr,intptr)

When I look in AppCenter, it logs the exception ONLY with the bad stack trace. So that's a problem... The other problem is that it completely ignored my Crashes.TrackError call, the exception with the good stack trace and properties set doesn't get added to AppCenter.

What am I missing?

If you do it the general way, in a try catch, does it work normally? — Bruno Caceiro

Miiite Miiite · Accepted Answer · 2019-01-25T08:54:33

Visual Studio AppCenter automatically catches .NET exceptions for you.

The Android code your posted earlier is not necessary. Without it, if your SDK is initialized correctly, you will receive the stacktraces in the dashboard.

AndroidEnvironment.UnhandledExceptionRaiser += LogException;

private void LogException (object sender, RaiseThrowableEventArgs e) {
        var exc = e.Exception;
        if (ShouldLogException (exc)) {
            // Log exception to AppCenter.
            var properties = AppCenterLoggingSink.GetProperties ();
            Crashes.TrackError (exc, properties);
            e.Handled = true;
        }
    }

The code above is only for the Android platform. So basically you're getting the Android error, meaning that your app crashed, and you send that to appcenter. So the behavior seems logic to me.

Let AppCenter catch crashes on its own, and your should be fine for .NET exceptions.

Unhandled Xamarin Android exceptions have bad stack trace when logging to Visual Studio App Center

1 Answers