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

Question

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.

Answer 1

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!

Answer 2

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.