Develop Reference

Xamarin Forms Android Store crashes when i download the app, debugs perfectly on phone from VS

This is my first commit on google play store. I am using Xamarin Forms and when i run my app localy on my android phone, i have no issues.
When I Archive and Distribute the App within VS using Archive Manager and download it on my phone, or any other android phone, the App crashes before going to the 1st screen.
Under Play Console I can see the following error on the Pre-Lunch report
Blockquote
FATAL EXCEPTION: main
Process: com.*****.*****, PID: 8647
android.runtime.JavaProxyThrowable: Xamarin.Forms.Xaml.XamlParseException: Position 30:125. No method OnMenuItemSelected2 found on type *****.Menus.MainPageV2
at Xamarin.Forms.Xaml.ApplyPropertiesVisitor.SetPropertyValue (System.Object xamlelement, Xamarin.Forms.Xaml.XmlName propertyName, System.Object value, System.Object rootElement, Xamarin.Forms.Xaml.INode node, Xamarin.Forms.Xaml.HydrationContext context, System.Xml.IXmlLineInfo lineInfo) [0x000ee] in :0
at Xamarin.Forms.Xaml.ApplyPropertiesVisitor.Visit (Xamarin.Forms.Xaml.ValueNode node, Xamarin.Forms.Xaml.INode parentNode) [0x00072] in :0
at Xamarin.Forms.Xaml.ValueNode.Accept (Xamarin.Forms.Xaml.IXamlNodeVisitor visitor, Xamarin.Forms.Xaml.INode parentNode) [0x00000] in :0
at Xamarin.Forms.Xaml.ElementNode.Accept (Xamarin.Forms.Xaml.IXamlNodeVisitor visitor, Xamarin.Forms.Xaml.INode parentNode) [0x00043] in :0
at Xamarin.Forms.Xaml.ElementNode.Accept (Xamarin.Forms.Xaml.IXamlNodeVisitor visitor, Xamarin.Forms.Xaml.INode parentNode) [0x00078] in :0
at Xamarin.Forms.Xaml.ElementNode.Accept (Xamarin.Forms.Xaml.IXamlNodeVisitor visitor, Xamarin.Forms.Xaml.INode parentNode) [0x00078] in :0
at Xamarin.Forms.Xaml.RootNode.Accept (Xamarin.Forms.Xaml.IXamlNodeVisitor visitor, Xamarin.Forms.Xaml.INode parentNode) [0x00043] in :0
at Xamarin.Forms.Xaml.XamlLoader.Visit (Xamarin.Forms.Xaml.RootNode rootnode, Xamarin.Forms.Xaml.HydrationContext visitorContext) [0x00083] in :0
at Xamarin.Forms.Xaml.XamlLoader.Load (System.Object view, System.String xaml) [0x0008f] in :0
at Xamarin.Forms.Xaml.XamlLoader.Load (System.Object view, System.Type callingType) [0x0002f] in :0
at Xamarin.Forms.Xaml.Extensions.LoadFromXaml[TXaml] (TXaml view, System.Type callingType) [0x00000] in :0
at ****.Menus.MainPageV2.InitializeComponent () [0x00000] in :0
at ****.Menus.MainPageV2..ctor () [0x00006] in :0
at ****.App..ctor () [0x0000c] in :0
at ****.Droid.MainActivity.OnCreate (Android.OS.Bundle bundle) [0x00022] in :0
at Android.App.Activity.n_OnCreate_Landroid_os_Bundle_ (System.IntPtr jnienv, System.IntPtr native__this, System.IntPtr native_savedInstanceState) [0x0000f] in :0
at (wrapper dynamic-method) System.Object:efb18139-d766-47ea-a9bd-57beaf3952f0 (intptr,intptr,intptr)
at md5684c7b5241d0a7c4d4ea0533a804cbec.MainActivity.n_onCreate(Native Method)
at md5684c7b5241d0a7c4d4ea0533a804cbec.MainActivity.onCreate(MainActivity.java:29)
at android.app.Activity.performCreate(Activity.java:6975)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1213)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2770)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2892)
at android.app.ActivityThread.-wrap11(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1593)
at android.os.Handler.dispatchMessage(Handler.java:105)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6541)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:767)
The thing is that my Menus.MainPageV2 includes OnMenuItemSelected2 which is run just fine when testing localy
The automated Google Test results on the on the Pre-Lunch report are failing for all testing devices with the same error.
Things I tried changing, re-Archiving and Distributing:
- Closed VS, cleaned bin, obj directories and Re-Built
- Upgraded to the latest Xamarin Forms Nuget
- Linking with None, Sdk and User Assemblies, Sdk Assemblies only
Anyone have any ideas on what else i might try to get this to work ?
Thank you for your time.

Xamarin forms app crashing on startup regardless of Debug/Release

I have had this weird problem with my Xamarin Forms app. It seems to crash on startup. I have tried changing the Android Linker settings but regardless of the settings it still seems to crash. It used to work on Debug mode but not working anymore. I have tried deleting the bin and obj files. I have tried deleting and updating the NuGet packages. Any help would be appreciated. I have checked in the "Main Activity" method for any missing constructors but there doesn't seem to be any missing.
Here is the stack trace below:
[ERROR] FATAL UNHANDLED EXCEPTION: System.NotSupportedException: Could not activate JNI Handle 0xbfe1bd38 (key_handle 0xfcb6ecf) of Java type 'md5a4d2fdb8e3028a798e3d0ab6628e2c4b/MainActivity' as managed type 'TeaTotal.Droid.MainActivity'. ---> System.TypeInitializationException: The type initializer for 'TeaTotal.Droid.MainActivity' threw an exception. ---> System.MissingMethodException: Default constructor not found for type Microsoft.WindowsAzure.MobileServices.CurrentPlatform
at System.RuntimeType.CreateInstanceMono (System.Boolean nonPublic) [0x00085] in /Users/builder/data/lanes/4468/f913a78a/source/mono/mcs/class/corlib/ReferenceSources/RuntimeType.cs:171
at System.RuntimeType.CreateInstanceSlow (System.Boolean publicOnly, System.Boolean skipCheckThis, System.Boolean fillCache, System.Threading.StackCrawlMark& stackMark) [0x0001a] in /Users/builder/data/lanes/4468/f913a78a/source/mono/mcs/class/corlib/ReferenceSources/RuntimeType.cs:153
at System.RuntimeType.CreateInstanceDefaultCtor (System.Boolean publicOnly, System.Boolean skipCheckThis, System.Boolean fillCache, System.Threading.StackCrawlMark& stackMark) [0x0002a] in /Users/builder/data/lanes/4468/f913a78a/source/mono/mcs/class/referencesource/mscorlib/system/rttype.cs:5638
at System.Activator.CreateInstance (System.Type type, System.Boolean nonPublic) [0x00040] in /Users/builder/data/lanes/4468/f913a78a/source/mono/mcs/class/referencesource/mscorlib/system/activator.cs:201
at System.Activator.CreateInstance (System.Type type) [0x00000] in /Users/builder/data/lanes/4468/f913a78a/source/mono/mcs/class/referencesource/mscorlib/system/activator.cs:134
at Microsoft.WindowsAzure.MobileServices.Platform.get_Instance () [0x00054] in <77043900ca604149b85ba57dba9fe35b>:0
at Microsoft.WindowsAzure.MobileServices.MobileServiceClient.GetApplicationInstallationId () [0x00004] in <77043900ca604149b85ba57dba9fe35b>:0
at Microsoft.WindowsAzure.MobileServices.MobileServiceClient..ctor (System.Uri applicationUri, System.String applicationKey, System.Net.Http.HttpMessageHandler[] handlers) [0x00028] in <77043900ca604149b85ba57dba9fe35b>:0
at Microsoft.WindowsAzure.MobileServices.MobileServiceClient..ctor (System.Uri applicationUri, System.String applicationKey) [0x00000] in <77043900ca604149b85ba57dba9fe35b>:0
at Microsoft.WindowsAzure.MobileServices.MobileServiceClient..ctor (System.Uri applicationUri) [0x00000] in <77043900ca604149b85ba57dba9fe35b>:0
at Microsoft.WindowsAzure.MobileServices.MobileServiceClient..ctor (System.String applicationUrl) [0x00007] in <77043900ca604149b85ba57dba9fe35b>:0
at TeaTotal.Droid.MainActivity..cctor () [0x00000] in C:\TT\Droid\MainActivity.cs:31

UITest failed with : "SetUp : System.InvalidOperationException"

I can't use UITest anymore with my xamarin project since the last update of xamarin on the stable channel with Xcode 8.2.
Everytime, when I launch the test, I have an error : "SetUp : System.InvalidOperationException : Sequence contains no matching element". My test series doesn't change from a long time and works well before...
So I don't know how to correct this problem now...
The stack trace :
at System.Linq.Enumerable.First[TSource] (System.Collections.Generic.IEnumerable1[T] source, System.Func2[T,TResult] predicate) [0x00065] in /private/tmp/source-mono-4.6.0/bockbuild-mono-4.6.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/System.Core/System/Linq/Enumerable.cs:965
at Xamarin.UITest.iOS.Instruments.GetAutomationTemplatePath () [0x00031] in :0
at Xamarin.UITest.iOS.Instruments.StartInstrumentsInternal (System.String targetApplication, Xamarin.UITest.iOS.iOSRunType runType, System.String deviceId, System.String runLoopPath, Xamarin.UITest.Configuration.AppDataMode appDataMode, System.Predicate`1[T] dropLine) [0x00006] in :0
at Xamarin.UITest.iOS.Instruments.StartInstruments (System.String targetApplication, Xamarin.UITest.iOS.iOSRunType runType, System.String deviceId, Xamarin.UITest.Configuration.AppDataMode appDataMode) [0x00012] in :0
at Xamarin.UITest.iOS.iOSAppLauncher.RunAppInEmulatorInternal (System.String application, Xamarin.UITest.iOS.Instruments instruments, Xamarin.UITest.Shared.Http.HttpClient httpClient, System.Uri deviceUri, Xamarin.UITest.Shared.Artifacts.ArtifactFolder artifactFolder, Xamarin.UITest.Configuration.AppDataMode appDataMode, System.String deviceIdentifier) [0x00095] in :0
at Xamarin.UITest.iOS.iOSAppLauncher.RunAppInEmulator (Xamarin.UITest.Shared.iOS.AppBundle appBundle, Xamarin.UITest.iOS.Instruments instruments, Xamarin.UITest.Shared.Http.HttpClient httpClient, System.Uri deviceUri, Xamarin.UITest.Shared.Artifacts.ArtifactFolder artifactFolder, Xamarin.UITest.Configuration.AppDataMode appDataMode, System.String deviceIdentifier) [0x00099] in :0
at Xamarin.UITest.iOS.iOSAppLauncher.LaunchApp (Xamarin.UITest.Configuration.IiOSAppConfiguration appConfiguration, Xamarin.UITest.Shared.Http.HttpClient httpClient, Xamarin.UITest.TestCloud.TestCloudiOSAppConfiguration testCloudAppConfiguration, Xamarin.UITest.Shared.Http.HttpClient testCloudWsClient) [0x000e4] in :0
at Xamarin.UITest.iOS.iOSApp..ctor (Xamarin.UITest.Configuration.IiOSAppConfiguration appConfiguration) [0x002db] in :0
at Xamarin.UITest.Configuration.iOSAppConfigurator.StartApp (Xamarin.UITest.Configuration.AppDataMode appDataMode) [0x00017] in :0
at Ac.Test.TestV35.BeforeEachTest () [0x00012] in /Users/ShaprAdmin/Documents/ac/Ac.Test/TestV35.cs:17
at (wrapper managed-to-native) System.Reflection.MonoMethod:InternalInvoke (System.Reflection.MonoMethod,object,object[],System.Exception&)
at System.Reflection.MonoMethod.Invoke (System.Object obj, System.Reflection.BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) [0x00038] in /private/tmp/source-mono-4.6.0/bockbuild-mono-4.6.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/corlib/System.Reflection/MonoMethod.cs:305
Thank you!

try to grab the newest Xcode and
then beside proper NUnit version (2.6.x and proper NUnitTestAdapter 2.1.0)
try do upgrade/downgrade the Xamarin.UITest package to version 2.5.
For me it was not working (with same error) for 2.7 for 2.5 it's ok.
Regards,

Xamarin.IOS MvvmCross App throws NullReference Exception in ViewDidLoad method in iOS9

I am working on an existing Xamarin iOS application with a PCL and uses MvvmCross for IoC and Databinding. Built on MvvmCross 3.1.1
The App looks like a TabControl App but it is buttons on the MainViewCotnroller giving the Tab feel to it. Views are declared in the Storyboard and in the MainViewController,
PrepareForSegue(UIStoryboardSegue segue, NSObject sender) method
is overridden to load the selected "Tab" View based on the Segue selected - like below
if (segue.Identifier == "FirstSegue")
{
var dest = segue.DestinationViewController as FirstView;
dest.Request = new MvxViewModelRequest<FirstViewModel>(null, null, new MvxRequestedBy());
foreach (UIView v in src.placeHolderView.Subviews)
{
v.RemoveFromSuperview();
}
dest.View.Frame = new CGRect(0f, 0f, w, h);
src.placeHolderView.Add(dest.View);
}
The App runs fine on iPhones with iOS 7.1 till 8.4.
Just before iOS 9 was released I did a test installation for the App on iPhone 6 with iOS 9.1 beta and the App crashed on loading. I retrieved the device logs (below) and analysed that the problem is in the guts of the MvvmCross ViewDidLoad method. I updated the latest SDKs (XCode 7, Xamarin.IOS 9.0) and followed instructions provided by Xamarin and compiled the App again using the latest SDKs same error. Updated the Nuget package reference for MvvmCross to 3.5.1 and still the same issue
The issues is there is a null reference at Line 44 in the 3.5 MvvMCross Source Code in GitHub
Note: This piece of code has not changed since 3.1 at least and 3.5.1 is the latest in the nuget for MvvmCross
Stack Trace below (App Names, Project Names changed for security reasons):
2015-09-21 11:06:26.991 MyApp[1210:60b] Unhandled managed exception:
Object reference not set to an instance of an object (System.NullReferenceException)
at Cirrious.CrossCore.Mvx.Resolve[IMvxViewModelLoader] () [0x00006] in <filename unknown>:0
at Cirrious.MvvmCross.Touch.Views.MvxViewControllerExtensionMethods.LoadViewModel (IMvxTouchView touchView) [0x00057] in <filename unknown>:0
at Cirrious.MvvmCross.Views.MvxViewExtensionMethods.OnViewCreate (IMvxView view, System.Func`1 viewModelLoader) [0x00012] in <filename unknown>:0
at Cirrious.MvvmCross.Touch.Views.MvxViewControllerExtensionMethods.OnViewCreate (IMvxTouchView touchView) [0x00001] in <filename unknown>:0
at Cirrious.MvvmCross.Touch.Views.MvxViewControllerAdapter.HandleViewDidLoadCalled (System.Object sender, System.EventArgs e) [0x00007] in <filename unknown>:0
at (wrapper delegate-invoke) <Module>:invoke_void_object_EventArgs (object,System.EventArgs)
at Cirrious.CrossCore.Core.MvxDelegateExtensionMethods.Raise (System.EventH
andler eventHandler, System.Object sender) [0x00004] in <filename unknown>:0
at Cirrious.CrossCore.Touch.Views.MvxEventSourceTableViewController.ViewDidLoad () [0x00006] in <filename unknown>:0
at MyProject.Touch.MostPurchasedView.ViewDidLoad () [0x00048] in d:\Working\Repo\MyApp\<MyProjectName>\MyProject.Touch\Views\OneOfTheView.cs:31
at (wrapper managed-to-native) ObjCRuntime.Messaging:IntPtr_objc_msgSendSuper (intptr,intptr)
at UIKit.UIViewController.get_View () [0x00030] in /Users/builder/data/lanes/2077/d230615b/source/maccore/src/build/ios/native/UIKit/UIViewController.g.cs:2632
at MyProject.Touch.HomeViewController.PrepareForSegue (UIKit.UIStoryboardSegue segue, Foundation.NSObject sender) [0x0016a] in d:\Working\Repo\MyApp\MyProject.Mobile\MyProject.Touch\HomeViewController.cs:335
at (wrapper managed-to-native) UIKit.UIApplication:UIApplicationMain (int,string[],intptr,intptr)
at
UIKit.UIApplication.Main (System.String[] args, IntPtr principal, IntPtr delegate) [0x00005] in /Users/builder/data/lanes/2077/d230615b/source/maccore/src/UIKit/UIApplication.cs:74
at UIKit.UIApplication.Main (System.String[] args, System.String principalClassName, System.String delegateClassName) [0x0001c] in /Users/builder/data/lanes/2077/d230615b/source/maccore/src/UIKit/UIApplication.cs:57
at MyProject.Touch.Application.Main (System.String[] args) [0x00001] in d:\Working\Repo\MyApp\MyProject.Mobile\MyProject.Touch\Main.cs:16
2015-09-21 11:06:26.994 MyApp[1210:60b] critical: Stacktrace:
Native stacktrace:
.....
I tried the above with just calling the below in the View.cs:
public override void ViewDidLoad()
{
try
{
base.ViewDidLoad();
}
catch (Exception ex)
{
// throw a toast msg in the UI
}
}
I disabled all the base.ViewDidLoad() in all the View.cs files in the ViewDidLoad override methods to take it to the next level and the same problem but inside the constructor of MvxSimpleTableViewSource class
Device Log below:
Object reference not set to an instance of an object (System.NullReferenceException)
at Cirrious.CrossCore.Mvx.TryResolve[IMvxTouchSystem] (IMvxTouchSystem& service) [0x00006] in <filename unknown>:0
at Cirrious.CrossCore.Touch.Platform.MvxIosMajorVersionChecker.ReadIsIosVersionOrHigher (Int32 target, Boolean defaultValue) [0x00000] in <filename unknown>:0
at Cirrious.CrossCore.Touch.Platform.MvxIosMajorVersionChecker..ctor (Int32 major, Boolean defaultValue) [0x00006] in <filename unknown>:0
at Cirrious.MvvmCross.Binding.Touch.Views.MvxSimpleTableViewSource..ctor (UIKit.UITableView tableView, System.String nibName, System.String cellIdentifier, Foundation.NSBundle bundle) [0x00000] in <filename unknown>:0
at MyProject.Touch.MostPurchasedView.ViewDidLoad () [0x00059] in d:\Working\Repo\MyApp\MyProject.Mobile\MyProject.Touch\Views\OneOfTheView.cs:42
at (wrapper managed-to-native) ObjCRuntime.Messaging:IntPtr_objc_msgSendSuper (intptr,intptr)
at UIKit.UIViewController.get_View () [0x00030] in /Users/builder/data/lanes/2077/d230615b/source/maccore/src/build/ios/native/UIKit/UIViewController.g.cs:2632
at MyProject.Touch.HomeViewController.PrepareForSegue (UIKit.UIStoryboardSegue segue, Foundation.NSObject sender) [0x0016a] in d:\Working\Repo\MyApp\MyProject.Mobile\MyProject.Touch\HomeViewController.cs:343
at (wrapper managed-to-native) UIKit.UIApplication:UIApplicationMain (int,string[],intptr,intptr)
at UIKit.UIApplication.Main (System.String[] args, IntPtr principal, IntPtr delegate) [0x00005] in /Users/builder/data/lanes/2077/d230615b/source/maccore/src/UIKit/UIApplication.cs:74
at UIKit.UIApplication.Main (System.String[] args, System.String principalClassName, System.String delegateClassName) [0x0001c] in /Users/builder/data/lanes/2077/d230615b/source/maccore/src/UIKit/UIApplication.cs:57
at MyProject.Touch.Application.Main (System.String[] args) [0x00001] in d:\Working\Repo\MyApp\MyProject.Mobile\MyProject.Touch\Main.cs:16
In short :
Only in iOS 9.1, MvvmCross 3.1.1 AND MvvmCross 3.5.1 has a NullReference Issue in line 44 of the MvxViewControllerExtensionMethods class which gets called during ViewDidLoad but works well with iOS 8.4 and below
I am just getting familiar with MvvmCross framework and unsure whether it is an issue with MvvmCross and iOS 9.
Has anyone come across this issue? Any help on this would be appreciated.
Note: The MvvmCross samples work fine with iOS9. So I believe it has to be something with the Tab implementation.

One thing is that MvvmCross 3.1.1 not is build for iOS unified code. This will prevent you from submitting your app. MvvmCross 4.0 is currently in beta, but i would recommend using it, because it has many fixes.
If the code crashes on line 44 while trying to resolve IMvxViewModelLoader, it probably means that you are missing some package where the IMvxViewModelLoader is.

App crashes in release mode and not in debug mode - Xamarin Forms

I am building a cross platform app and i want to release it to testers, but it doesn't work when i am deploying it in release mode. As far as exceptions go i do not get any. As stated in the question it works in debug mode. The app just goes to splashscreen and crashes. I ran the original app through test fairy and got this exception:
java.lang.RuntimeException: java.lang.reflect.InvocationTargetException
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1099)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.reflect.InvocationTargetException
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1283)
... 2 more
Caused by: md52ce486a14f4bcd95899665e9d932190b.JavaProxyThrowable: System.IO.FileNotFoundException: Could not load file or assembly '<Censored: Name of forms class library>.dll' or one of its dependencies. The system cannot find the file specified.
File name: '<Censored: Name of forms class library>.dll'
at System.AppDomain.Load (System.Reflection.AssemblyName assemblyRef, System.Security.Policy.Evidence assemblySecurity) [0x00000] in :0
at System.AppDomain.Load (System.Reflection.AssemblyName assemblyRef) [0x00000] in :0
at (wrapper remoting-invoke-with-check) System.AppDomain:Load (System.Reflection.AssemblyName)
at System.Reflection.Assembly.Load (System.Reflection.AssemblyName assemblyRef) [0x00000] in :0
at Xamarin.Forms.Xaml.XamlParser.GetElementType (Xamarin.Forms.Xaml.XmlType xmlType, IXmlLineInfo xmlInfo, System.Reflection.Assembly currentAssembly, Xamarin.Forms.Xaml.XamlParseException& exception) [0x00000] in :0
at (wrapper delegate-invoke) :invoke_Type_XmlType_IXmlLineInfo_Assembly_XamlParseException& (Xamarin.Forms.Xaml.XmlType,System.Xml.IXmlLineInfo,System.Reflection.Assembly,Xamarin.Forms.Xaml.XamlParseException&)
at Xamarin.Forms.Xaml.XamlTypeResolver.Resolve (System.String qualifiedTypeName, IServiceProvider serviceProvider, Xamarin.Forms.Xaml.XamlParseException& exception) [0x00000] in :0
at Xamarin.Forms.Xaml.XamlTypeResolver.TryResolve (System.String qualifiedTypeName, System.Type& type) [0x00000] in :0
at Xamarin.Forms.Xaml.ExpandMarkupsVisitor+MarkupExpansionParser.Parse (System.String match, System.String& remaining, IServiceProvider serviceProvider) [0x00000] in :0
at Xamarin.Forms.Xaml.ExpandMarkupsVisitor.ParseExpression (System.String& expression, IXmlNamespaceResolver nsResolver, IXmlLineInfo xmlLineInfo, INode node, INode parentNode) [0x00000] in :0
at Xamarin.Forms.Xaml.ExpandMarkupsVisitor.Visit (Xamarin.Forms.Xaml.MarkupNode markupnode, INode parentNode) [0x00000] in :0
at Xamarin.Forms.Xaml.MarkupNode.Accept (IXamlNodeVisitor visitor, INode parentNode) [0x00000] in :0
at Xamarin.Forms.Xaml.ElementNode.Accept (IXamlNodeVisitor visitor, INode parentNode) [0x00000] in :0
at Xamarin.Forms.Xaml.ElementNode.Accept (IXamlNodeVisitor visitor, INode parentNode) [0x00000] in :0
at Xamarin.Forms.Xaml.RootNode.Accept (IXamlNodeVisitor visitor, INode parentNode) [0x00000] in :0
at Xamarin.Forms.Xaml.XamlLoader.Load (Xamarin.Forms.BindableObject view, System.String xaml) [0x00000] in :0
at Xamarin.Forms.Xaml.XamlLoader.Load (Xamarin.Forms.BindableObject view, System.Type callingType) [0x00000] in :0
at Xamarin.Forms.Xaml.Extensions.LoadFromXaml[LoginPage] (<Censored>.Login.LoginPage view, System.Type callingType) [0x00000] in :0
at <Censored>.Login.LoginPage.InitializeComponent () [0x00000] in :0
at <Censored>.Login.LoginPage..ctor () [0x00000] in :0
at <Censored>.App.b__0 () [0x00000] in :0
at <Censored>.ViewFactory.Resolve[LoginViewModel] (<Censored>.Login.LoginViewModel viewModel) [0x00000] in :0
at <Censored>.App..ctor () [0x00000] in :0
at md5b406f03a919343acc4f3b337a44e1248.MainActivity.n_onCreate(Native Method)
at md5b406f03a919343acc4f3b337a44e1248.MainActivity.onCreate(MainActivity.java:28)
at android.app.Activity.performCreate(Activity.java:5458)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1093)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2376)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2470)
at android.app.ActivityThread.access$900(ActivityThread.java:174)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1307)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:146)
at android.app.ActivityThread.main(ActivityThread.java:5593)
... 5 more
I cannot show you the source code, but i have reproduced the error in a new test solution.
Here is a link to the repository with the test project. It is just a project using MVVM with Xamarin Forms.

Fixed it by manually deleting all obj folders and all bin folders in the entire solution.
Edit: Came back again and now this fix does not work!

If your solution works in Debug mode, but not in Release mode, it might be an issue with the Linker.
Right Click on your specific project (not Solution) -> Android Options -> Linker -> Choose "None" in Linking. This will include all dlls in the Release Library.