Mediaplugin: NullReferenceException - FormsAppCompatActivity.InternalSetPage

[alwydl]

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Bug Information

Version Number of Plugin: 2.6.2 and 3.1.1
Device Tested On: Zenfone 2
Simulator Tested On: none
Version of VS: 2015 Comunnity 3
Version of Xamarin: 4.8.188
Versions of other things you are using:

Steps to reproduce the Behavior

Version previous to SDK 25 in android was working fine. After updated the SDK and Plugin version, it stopped working.
Using FormsAppCompatActivity in Android

Expected Behavior

Not block the app and allow to use camera

Actual Behavior

LoadApplication(new App) is giving the following exception:

System.NullReferenceException: Object reference not set to an instance of an object.
at Xamarin.Forms.Platform.Android.FormsAppCompatActivity.InternalSetPage (Xamarin.Forms.Page page) [0x0005e] in D:\agent_work\1\s\Xamarin.Forms.Platform.Android\AppCompat\FormsAppCompatActivity.cs:315
at Xamarin.Forms.Platform.Android.FormsAppCompatActivity.SetMainPage () [0x00000] in D:\agent_work\1\s\Xamarin.Forms.Platform.Android\AppCompat\FormsAppCompatActivity.cs:343
at Xamarin.Forms.Platform.Android.FormsAppCompatActivity.LoadApplication (Xamarin.Forms.Application application) [0x0025c] in D:\agent_work\1\s\Xamarin.Forms.Platform.Android\AppCompat\FormsAppCompatActivity.cs:139
at Shappa.Droid.MainActivity+d__0.MoveNext () [0x001b9] in C:\Andre\Shappa\Shappa\Shappa\Shappa.Droid\MainActivity.cs:62

Code snippet

https://gist.github.com/alwydl/e440f3e3745947ec4ad88597606a1a2f

Screenshots

If I take out the initialization process added for this new version (override permission, assemblyInfo and manifest) it enters the App class, but the camera does not work.

[MichaelGiger]

I have the same issue!
Plugin Version 3.1.2

[jamesmontemagno]

What version of Xamarin.Forms? Probably a regression on their part.

[MichaelGiger]

Xamarin.Forms v2.5.0.122203

[MichaelGiger]

It works with Visual Studio v15.4.2!
It's not working on my local development computer. I have installed Visual Studio v15.5.3

[alwydl]

It was the latest Version of forms here too. But Ive made a rollback and kept it downgraded for now. My VS is 2015, 14.0.25431.01 update 3 (but I dont think it is this)

[jamesmontemagno]

Should be reported against Xamarin.Forms or Xamarin.Android repos as it has nothing to do with the plugin that I can tell.

[PaulVrugt]

this happened to me too. Cleaning the solution, closing visual studio, deleting all obj and bin folder, restarting studio, rebuilding and trying again helped.

[Soarc]

Same here. Delete bin/obj, clean rebuild helped me too.
Hope someday xamarin will be idempotent to rebuilds. :(

[developMediaSoft]

Hope you don't mind me updating this thread here, it's what the search engine turns up with for this error:
I found this error to be caused by the Resources/values/styles.xml file in my Xamarin.Android project - in particular, I've resolved it by removing the "android:" prefix from the name of each item node.

[wireless-r]

I came here from Google as well. For me it was solved by unchecking "Enable ProGuard" in Android options.

[MonkeyBrush]

See this Bug in Xamarin. I had to downgrade from Xamarin.Android.Support.* versions 27.0.2 to 26.1.0.1.
https://bugzilla.xamarin.com/show_bug.cgi?id=36287

[PaulVrugt]

@developMediaSoft

This seems to have fixed the issue for me too. I had an "android:textAllCaps" and "android:windowNoTitle" item in styles.xml, removing the "android:" from them seems to resolve the issue

[nbsoftware]

Same a @wireless-r , just unchecking "Enable Proguard" (not touching anything else) on release build did work around the issue.

[bruzkovsky]

This is an issue with X.F and it is tracked here: https://github.com/xamarin/Xamarin.Forms/issues/2148