WatchKit button action does not work on simulators running WatchOS 7

[caveda]

Controller actions associated with buttons on WatchOS v7 are never called and instead produce errors:

decode error: tag 0 doesn't exist in schema for class BKSHIDEventDigitizerAttributes
decode error: tag 11 doesn't exist in schema for class BKSHIDEventDigitizerPathAttributes
could not decode attributes:Error Domain=NSPOSIXErrorDomain Code=22 "Invalid argument" UserInfo={NSLocalizedDescription=decode error: mystery error (at end) decoding class BKSHIDEventDigitizerPathAttributes}

Same application run on Simulator WatchOS 6.2 works without error. The issue can be reproduced with existing projects as well as new ones targeting any WatchOS version.

Steps to Reproduce

1. Download Xamarin WatchOS sample WatchConnectivity.
2. Build and deploy the app on Simulator iPhone11 Pro iOS 14 paired with Simulator Watch Series 6 - 44mm - WatchOS 7. Actually it can be reproduced on any watch simulator running WatchOS v.7.
3. On the Watch app, tap on any of the buttons with fruits.
   

Same application run on Watch Simulator v.6.2.1 works without error.

Expected Behavior

The associated action is executed correctly and the message is received in the iOS app.

Actual Behavior

Actions declared on controller are never executed and the following errors appear in log/Console:

WatchConnectivityOnWatchExtension	decode error: tag 0 doesn't exist in schema for class BKSHIDEventDigitizerAttributes
WatchConnectivityOnWatchExtension	decode error: tag 0 doesn't exist in schema for class BKSHIDEventDigitizerPathAttributes
BKSHIDEventDigitizerPathAttributes could not decode attributes:Error Domain=NSPOSIXErrorDomain Code=22 "Invalid argument" UserInfo={NSLocalizedDescription=decode error: mystery error (at end) decoding class BKSHIDEventDigitizerPathAttributes}

Environment

=== Visual Studio Community 2019 for Mac ===

Version 8.7.8 (build 4)
Installation UUID: 17488cdb-a2f4-41c8-9862-3b81132a1111
	GTK+ 2.24.23 (Raleigh theme)
	Xamarin.Mac 6.18.0.23 (d16-6 / 088c73638)

	Package version: 612000093

=== Mono Framework MDK ===

Runtime:
	Mono 6.12.0.93 (2020-02/620cf538206) (64-bit)
	Package version: 612000093

=== Roslyn (Language Service) ===

3.7.0-6.20427.1+18ede13943b0bfae1b44ef078b2f3923159bcd32

=== NuGet ===

Version: 5.7.0.6702

=== .NET Core SDK ===

SDK: /usr/local/share/dotnet/sdk/3.1.402/Sdks
SDK Versions:
	3.1.402
	3.1.300
	3.1.100
	3.0.100
	2.1.701
	2.1.505
	2.1.504
	2.1.302
MSBuild SDKs: /Library/Frameworks/Mono.framework/Versions/6.12.0/lib/mono/msbuild/Current/bin/Sdks

=== .NET Core Runtime ===

Runtime: /usr/local/share/dotnet/dotnet
Runtime Versions:
	3.1.8
	3.1.4
	3.1.0
	3.0.0
	2.1.22
	2.1.18
	2.1.14
	2.1.13
	2.1.12
	2.1.9
	2.1.8
	2.1.2

=== Xamarin.Profiler ===

Version: 1.6.12.29
Location: /Applications/Xamarin Profiler.app/Contents/MacOS/Xamarin Profiler

=== Updater ===

Version: 11

=== Apple Developer Tools ===

Xcode 12.0 (17219)
Build 12A7209

=== Xamarin.Mac ===

Version: 6.20.2.2 (Visual Studio Community)
Hash: 817b6f72a
Branch: d16-7
Build date: 2020-07-18 18:44:59-0400

=== Xamarin.iOS ===

Version: 14.0.0.0 (Visual Studio Community)
Hash: 7ec3751a1
Branch: xcode12
Build date: 2020-09-16 11:33:15-0400

=== Xamarin Designer ===

Version: 16.7.0.495
Hash: 03d50a221
Branch: remotes/origin/d16-7-vsmac
Build date: 2020-08-28 13:12:52 UTC

=== Xamarin.Android ===

Version: 11.0.2.0 (Visual Studio Community)
Commit: xamarin-android/d16-7/025fde9
Android SDK: /Users/<user>/Library/Developer/Xamarin/android-sdk-macosx
	Supported Android versions:
		4.4 (API level 19)
		6.0 (API level 23)
		7.0 (API level 24)
		8.1 (API level 27)

SDK Tools Version: 26.1.1
SDK Platform Tools Version: 29.0.5
SDK Build Tools Version: 29.0.2

Build Information: 
Mono: 83105ba
Java.Interop: xamarin/java.interop/d16-7@1f3388a
ProGuard: Guardsquare/proguard/proguard6.2.2@ebe9000
SQLite: xamarin/sqlite/3.32.1@1a3276b
Xamarin.Android Tools: xamarin/xamarin-android-tools/d16-7@017078f

=== Microsoft OpenJDK for Mobile ===

Java SDK: /Users/<user>/Library/Developer/Xamarin/jdk/microsoft_dist_openjdk_8.0.25
1.8.0-25
Android Designer EPL code available here:
https://github.com/xamarin/AndroidDesigner.EPL

=== Android SDK Manager ===

Version: 16.7.0.13
Hash: 8380518
Branch: remotes/origin/d16-7~2
Build date: 2020-09-16 05:12:24 UTC

=== Android Device Manager ===

Version: 16.7.0.24
Hash: bb090a3
Branch: remotes/origin/d16-7
Build date: 2020-09-16 05:12:46 UTC

=== Build Information ===

Release ID: 807080004
Git revision: 9ea7bef96d65cdc3f4288014a799026ccb1993bc
Build date: 2020-09-16 17:22:54-04
Build branch: release-8.7
Xamarin extensions: 9ea7bef96d65cdc3f4288014a799026ccb1993bc

=== Operating System ===

Mac OS X 10.15.6
Darwin 19.6.0 Darwin Kernel Version 19.6.0
    Thu Jun 18 20:49:00 PDT 2020
    root:xnu-6153.141.1~1/RELEASE_X86_64 x86_64

Build Logs

Example Project (If Possible)

https://github.com/xamarin/ios-samples/tree/master/watchOS/WatchConnectivity

[jigneshbodarya]

Any updates?

[CR4567]

same issue here...
is the xamarin watchos community so small, that almost nobody recognizes this huge problem?

[appsure]

Look as if this may cover it: #10133

[motoko89]

This really puts me in a tough spot. Having companion watch app is a selling point for one of my apps and this plus other breaking issues in the past gives them bad impressions

[jigneshbodarya]

Any updates here?

Guys if you can't do it. please close support for watchOS, so we don't do buggy watch app with your broken support. you can work on other functions which remain from very long time.

[ThaerM]

Any update for this issues?

[Harshadcse]

Any update for these issues? We can't deliver our application without this feature. Please fix ASAP

[rolfbjarne]

Closing, since watchOS isn't supported in .NET, and Xamarin is not supported anymore.