Uno: Creating solution with Uno default templates yields round about 20,000 errors

[SetTrend]

Current behavior

After having created a mint Uno App solution, and after having updated all Uno NuGet packages, Visual Studio 2019 (latest) shows 19,666 errors plus warnings and messages:

This is highly confusing and blocking me from developing using Uno.

See (just click):

Build log

1>------ Rebuild All started: Project: FrontEnd.Droid, Configuration: Debug Any CPU ------
2>------ Skipped Rebuild All: Project: FrontEnd.iOS, Configuration: Debug iPhone ------
2>Project not selected to build for this solution configuration 
3>------ Skipped Rebuild All: Project: FrontEnd.UWP, Configuration: Debug x86 ------
3>Project not selected to build for this solution configuration 
4>------ Rebuild All started: Project: FrontEnd.Wasm, Configuration: Debug Any CPU ------
5>------ Skipped Rebuild All: Project: FrontEnd.macOS, Configuration: Debug iPhoneSimulator ------
5>Project not selected to build for this solution configuration 
4>D:\Documents\Visual Studio-Projekte\Uno\MyUnoApp\FrontEnd\FrontEnd.Shared\App.xaml.cs(64,9,64,33): warning Uno0001: Windows.ApplicationModel.Activation.LaunchActivatedEventArgs.PreviousExecutionState is not implemented in Uno
4>D:\Documents\Visual Studio-Projekte\Uno\MyUnoApp\FrontEnd\FrontEnd.Shared\App.xaml.cs(73,8,73,28): warning Uno0001: Windows.ApplicationModel.Activation.LaunchActivatedEventArgs.PrelaunchActivated is not implemented in Uno
4>FrontEnd.Wasm -> D:\Documents\Visual Studio-Projekte\Uno\MyUnoApp\FrontEnd\FrontEnd.Wasm\bin\Debug\netstandard2.0\FrontEnd.Wasm.dll
1>D:\Documents\Visual Studio-Projekte\Uno\MyUnoApp\FrontEnd\FrontEnd.Shared\App.xaml.cs(64,9,64,33): warning Uno0001: Windows.ApplicationModel.Activation.LaunchActivatedEventArgs.PreviousExecutionState is not implemented in Uno
1>D:\Documents\Visual Studio-Projekte\Uno\MyUnoApp\FrontEnd\FrontEnd.Shared\App.xaml.cs(73,8,73,28): warning Uno0001: Windows.ApplicationModel.Activation.LaunchActivatedEventArgs.PrelaunchActivated is not implemented in Uno
1>  FrontEnd.Droid -> D:\Documents\Visual Studio-Projekte\Uno\MyUnoApp\FrontEnd\FrontEnd.Droid\bin\Debug\FrontEnd.Droid.dll
4>Done building project "FrontEnd.Wasm.csproj".
========== Rebuild All: 2 succeeded, 0 failed, 3 skipped ==========

Even though build runs without errors, I'm not able to find my own bugs in this pile of other errors.

Expected behavior

Everything should install clean and smoothly; i.e. without any warnings, messages or errors.

How to reproduce it (as minimally and precisely as possible)

Here's my sample repo.

(It's just the plain, empty Uno template with updated Uno NuGet package references.)

Workaround

n/a

Environment

Visual Studio 2019

See (just click):

Visual Studio 2019 details

Microsoft Visual Studio Enterprise 2019
Version 16.7.2
VisualStudio.16.Release/16.7.2+30413.136
Microsoft .NET Framework
Version 4.8.03752

Installed Version: Enterprise

Architecture Diagrams and Analysis Tools   00433-90101-11830-AA167
Microsoft Architecture Diagrams and Analysis Tools

Visual C++ 2019   00433-90101-11830-AA167
Microsoft Visual C++ 2019

ADL Tools Service Provider   1.0
This package contains services used by Data Lake tools

ASA Service Provider   1.0

ASP.NET and Web Tools 2019   16.7.532.28833
ASP.NET and Web Tools 2019

ASP.NET Core Razor Language Services   16.1.0.2035807+72d099b977d3a85e65fa3b0614ca8cfc803fef02
Provides languages services for ASP.NET Core Razor.

ASP.NET Web Frameworks and Tools 2019   16.7.532.28833
For additional information, visit https://www.asp.net/

Azure App Service Tools v3.0.0   16.7.532.28833
Azure App Service Tools v3.0.0

Azure Data Lake Node   1.0
This package contains the Data Lake integration nodes for Server Explorer.

Azure Data Lake Tools for Visual Studio   2.4.6000.1
Microsoft Azure Data Lake Tools for Visual Studio

Azure Functions and Web Jobs Tools   16.7.532.28833
Azure Functions and Web Jobs Tools

Azure Stream Analytics Tools for Visual Studio   2.4.6000.1
Microsoft Azure Stream Analytics Tools for Visual Studio

C# Tools   3.7.0-6.20412.3+d3c3a44a4e7ad31cc75c59be0d3df4a19ff33878
C# components used in the IDE. Depending on your project type and settings, a different version of the compiler may be used.

Common Azure Tools   1.10
Provides common services for use by Azure Mobile Services and Microsoft Azure Tools.

Cookiecutter   16.7.20181.2
Provides tools for finding, instantiating and customizing templates in cookiecutter format.

Dotfuscator Community Edition   5.42.0.9514-e0e25f754
PreEmptive Protection - Dotfuscator CE

Extensibility Message Bus   1.2.6 (master@34d6af2)
Provides common messaging-based MEF services for loosely coupled Visual Studio extension components communication and integration.

Fabric.DiagnosticEvents   1.0
Fabric Diagnostic Events

GitHub.VisualStudio   2.11.104.25275
A Visual Studio Extension that brings the GitHub Flow into Visual Studio.

Microsoft Azure HDInsight Azure Node   2.4.6000.1
HDInsight Node under Azure Node

Microsoft Azure Hive Query Language Service   2.4.6000.1
Language service for Hive query

Microsoft Azure Service Fabric Tools for Visual Studio   16.0
Microsoft Azure Service Fabric Tools for Visual Studio

Microsoft Azure Stream Analytics Language Service   2.4.6000.1
Language service for Azure Stream Analytics

Microsoft Azure Stream Analytics Node   1.0
Azure Stream Analytics Node under Azure Node

Microsoft Azure Tools   2.9
Microsoft Azure Tools for Microsoft Visual Studio 2019 - v2.9.30701.1

Microsoft Continuous Delivery Tools for Visual Studio   0.4
Simplifying the configuration of Azure DevOps pipelines from within the Visual Studio IDE.

Microsoft JVM Debugger   1.0
Provides support for connecting the Visual Studio debugger to JDWP compatible Java Virtual Machines

Microsoft Library Manager   2.1.79+ge3567815aa.RR
Install client-side libraries easily to any web project

Microsoft MI-Based Debugger   1.0
Provides support for connecting Visual Studio to MI compatible debuggers

Microsoft Visual C++ Wizards   1.0
Microsoft Visual C++ Wizards

Microsoft Visual Studio Tools for Containers   1.1
Develop, run, validate your ASP.NET Core applications in the target environment. F5 your application directly into a container with debugging, or CTRL + F5 to edit & refresh your app without having to rebuild the container.

Microsoft Visual Studio VC Package   1.0
Microsoft Visual Studio VC Package

Mono Debugging for Visual Studio   16.7.5 (112c7bc)
Support for debugging Mono processes with Visual Studio.

Node.js Tools   1.5.20701.1 Commit Hash:b0da3724234b78593207434292d9f891440edea1
Adds support for developing and debugging Node.js apps in Visual Studio

NuGet Package Manager   5.7.0
NuGet Package Manager in Visual Studio. For more information about NuGet, visit https://docs.nuget.org/

Office Developer Tools for Visual Studio   16.0.30215.00
Microsoft Office Developer Tools for Visual Studio

ProjectServicesPackage Extension   1.0
ProjectServicesPackage Visual Studio Extension Detailed Info

Python   16.7.20181.2
Provides IntelliSense, projects, templates, debugging, interactive windows, and other support for Python developers.

Python - Conda support   16.7.20181.2
Conda support for Python projects.

Python - Django support   16.7.20181.2
Provides templates and integration for the Django web framework.

Python - IronPython support   16.7.20181.2
Provides templates and integration for IronPython-based projects.

Python - Profiling support   16.7.20181.2
Profiling support for Python projects.

Snapshot Debugging Extension   1.0
Snapshot Debugging Visual Studio Extension Detailed Info

SQL Server Data Tools   16.0.62008.03130
Microsoft SQL Server Data Tools

Test Adapter for Boost.Test   1.0
Enables Visual Studio's testing tools with unit tests written for Boost.Test.  The use terms and Third Party Notices are available in the extension installation directory.

Test Adapter for Google Test   1.0
Enables Visual Studio's testing tools with unit tests written for Google Test.  The use terms and Third Party Notices are available in the extension installation directory.

ToolWindowHostedEditor   1.0
Hosting json editor into a tool window

TypeScript Tools   16.0.20702.2001
TypeScript Tools for Microsoft Visual Studio

UnoPlatformPackage Extension   1.0
UnoPlatformPackage Visual Studio Extension Detailed Info

Visual Basic Tools   3.7.0-6.20412.3+d3c3a44a4e7ad31cc75c59be0d3df4a19ff33878
Visual Basic components used in the IDE. Depending on your project type and settings, a different version of the compiler may be used.

Visual C++ for Cross Platform Mobile Development (Android)   16.0.30309.115
Visual C++ for Cross Platform Mobile Development (Android)

Visual C++ for Cross Platform Mobile Development (iOS)   16.0.30309.115
Visual C++ for Cross Platform Mobile Development (iOS)

Visual C++ for Linux Development   1.0.9.30329
Visual C++ for Linux Development

Visual F# Tools 10.10.0.0 for F# 4.7   16.7.0-beta.20361.3+3ef6f0b514198c0bfa6c2c09fefe41a740b024d5
Microsoft Visual F# Tools 10.10.0.0 for F# 4.7

Visual Studio Code Debug Adapter Host Package   1.0
Interop layer for hosting Visual Studio Code debug adapters in Visual Studio

Visual Studio Container Tools Extensions (Preview)   1.0
View, manage, and diagnose containers within Visual Studio.

Visual Studio Tools for CMake   1.0
Visual Studio Tools for CMake

Visual Studio Tools for Containers   1.0
Visual Studio Tools for Containers

Visual Studio Tools for Kubernetes   1.0
Visual Studio Tools for Kubernetes

VisualStudio.DeviceLog   1.0
Information about my package

VisualStudio.Foo   1.0
Information about my package

VisualStudio.Mac   1.0
Mac Extension for Visual Studio

Workflow Manager Tools 1.0   1.0
This package contains the necessary Visual Studio integration components for Workflow Manager.

Xamarin   16.7.000.440 (d16-7@358f3c6)
Visual Studio extension to enable development for Xamarin.iOS and Xamarin.Android.

Xamarin Designer   16.7.0.495 (remotes/origin/d16-7@79c0c522c)
Visual Studio extension to enable Xamarin Designer tools in Visual Studio.

Xamarin Templates   16.7.85 (1bcbbdf)
Templates for building iOS, Android, and Windows apps with Xamarin and Xamarin.Forms.

Xamarin.Android SDK   11.0.2.0 (d16-7/025fde9)
Xamarin.Android Reference Assemblies and MSBuild support.
    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


Xamarin.iOS and Xamarin.Mac SDK   13.20.2.2 (817b6f72a)
Xamarin.iOS and Xamarin.Mac Reference Assemblies and MSBuild support.

Affected platform(s):

• [ ] iOS
• [X] Android
• [ ] WebAssembly
• [ ] WebAssembly renderers for Xamarin.Forms
• [ ] macOS
• [ ] Skia
  
  
  
  • [ ] WPF
  
  
  • [ ] GTK (Linux)
  
  
• [ ] Windows
• [ ] Build tasks
• [ ] Solution Templates

IDE:

• [ ] Visual Studio 2017 (version: )
• [X] Visual Studio 2019 (version: see above)
• [ ] Visual Studio for Mac (version: )
• [ ] Rider Windows (version: )
• [ ] Rider macOS (version: )
• [ ] Visual Studio Code (version: )

[ajpinedam]

Hi @SetTrend .

I have been trying to reproduce the error you mentioned here but I haven't been able to do it.

To start I created a File -> New project but also cloned the repository you provided. In both cases, I build the solution with 0 errors.

Build log

1>------ Rebuild All started: Project: FrontEnd.Droid, Configuration: Debug Any CPU ------
2>------ Skipped Rebuild All: Project: FrontEnd.iOS, Configuration: Debug iPhone ------
2>Project not selected to build for this solution configuration 
3>------ Skipped Rebuild All: Project: FrontEnd.UWP, Configuration: Debug x86 ------
3>Project not selected to build for this solution configuration 
4>------ Rebuild All started: Project: FrontEnd.Wasm, Configuration: Debug Any CPU ------
5>------ Skipped Rebuild All: Project: FrontEnd.macOS, Configuration: Debug iPhoneSimulator ------
5>Project not selected to build for this solution configuration 
4>C:\develop\uno\misc\Uno-Issue\FrontEnd\FrontEnd.Shared\App.xaml.cs(64,9,64,33): warning Uno0001: Windows.ApplicationModel.Activation.LaunchActivatedEventArgs.PreviousExecutionState is not implemented in Uno
4>C:\develop\uno\misc\Uno-Issue\FrontEnd\FrontEnd.Shared\App.xaml.cs(73,8,73,28): warning Uno0001: Windows.ApplicationModel.Activation.LaunchActivatedEventArgs.PrelaunchActivated is not implemented in Uno
4>FrontEnd.Wasm -> C:\develop\uno\misc\Uno-Issue\FrontEnd\FrontEnd.Wasm\bin\Debug\netstandard2.0\FrontEnd.Wasm.dll
1>C:\develop\uno\misc\Uno-Issue\FrontEnd\FrontEnd.Shared\App.xaml.cs(64,9,64,33): warning Uno0001: Windows.ApplicationModel.Activation.LaunchActivatedEventArgs.PreviousExecutionState is not implemented in Uno
1>C:\develop\uno\misc\Uno-Issue\FrontEnd\FrontEnd.Shared\App.xaml.cs(73,8,73,28): warning Uno0001: Windows.ApplicationModel.Activation.LaunchActivatedEventArgs.PrelaunchActivated is not implemented in Uno
1>  FrontEnd.Droid -> C:\develop\uno\misc\Uno-Issue\FrontEnd\FrontEnd.Droid\bin\Debug\FrontEnd.Droid.dll
4>Copying C:\Users\Andres Pineda\AppData\Local\Temp\mono-wasm-dd3c370ef1b\dbg-proxy\netcoreapp3.0\Microsoft.CodeAnalysis.CSharp.dll -> \\?\C:\develop\uno\misc\Uno-Issue\FrontEnd\FrontEnd.Wasm\obj\Debug\netstandard2.0\wasm-debugger\mono-wasm-dd3c370ef1b\Microsoft.CodeAnalysis.CSharp.dll
4>Copying C:\Users\Andres Pineda\AppData\Local\Temp\mono-wasm-dd3c370ef1b\dbg-proxy\netcoreapp3.0\Microsoft.CodeAnalysis.dll -> \\?\C:\develop\uno\misc\Uno-Issue\FrontEnd\FrontEnd.Wasm\obj\Debug\netstandard2.0\wasm-debugger\mono-wasm-dd3c370ef1b\Microsoft.CodeAnalysis.dll
4>Copying C:\Users\Andres Pineda\AppData\Local\Temp\mono-wasm-dd3c370ef1b\dbg-proxy\netcoreapp3.0\Microsoft.Extensions.Configuration.Abstractions.dll -> \\?\C:\develop\uno\misc\Uno-Issue\FrontEnd\FrontEnd.Wasm\obj\Debug\netstandard2.0\wasm-debugger\mono-wasm-dd3c370ef1b\Microsoft.Extensions.Configuration.Abstractions.dll
4>Copying C:\Users\Andres Pineda\AppData\Local\Temp\mono-wasm-dd3c370ef1b\dbg-proxy\netcoreapp3.0\Microsoft.Extensions.Configuration.Binder.dll -> \\?\C:\develop\uno\misc\Uno-Issue\FrontEnd\FrontEnd.Wasm\obj\Debug\netstandard2.0\wasm-debugger\mono-wasm-dd3c370ef1b\Microsoft.Extensions.Configuration.Binder.dll
4>Copying C:\Users\Andres Pineda\AppData\Local\Temp\mono-wasm-dd3c370ef1b\dbg-proxy\netcoreapp3.0\Microsoft.Extensions.Configuration.dll -> \\?\C:\develop\uno\misc\Uno-Issue\FrontEnd\FrontEnd.Wasm\obj\Debug\netstandard2.0\wasm-debugger\mono-wasm-dd3c370ef1b\Microsoft.Extensions.Configuration.dll
4>Copying C:\Users\Andres Pineda\AppData\Local\Temp\mono-wasm-dd3c370ef1b\dbg-proxy\netcoreapp3.0\Microsoft.Extensions.DependencyInjection.Abstractions.dll -> \\?\C:\develop\uno\misc\Uno-Issue\FrontEnd\FrontEnd.Wasm\obj\Debug\netstandard2.0\wasm-debugger\mono-wasm-dd3c370ef1b\Microsoft.Extensions.DependencyInjection.Abstractions.dll
4>Copying C:\Users\Andres Pineda\AppData\Local\Temp\mono-wasm-dd3c370ef1b\dbg-proxy\netcoreapp3.0\Microsoft.Extensions.DependencyInjection.dll -> \\?\C:\develop\uno\misc\Uno-Issue\FrontEnd\FrontEnd.Wasm\obj\Debug\netstandard2.0\wasm-debugger\mono-wasm-dd3c370ef1b\Microsoft.Extensions.DependencyInjection.dll
4>Copying C:\Users\Andres Pineda\AppData\Local\Temp\mono-wasm-dd3c370ef1b\dbg-proxy\netcoreapp3.0\Microsoft.Extensions.Logging.Abstractions.dll -> \\?\C:\develop\uno\misc\Uno-Issue\FrontEnd\FrontEnd.Wasm\obj\Debug\netstandard2.0\wasm-debugger\mono-wasm-dd3c370ef1b\Microsoft.Extensions.Logging.Abstractions.dll
4>Copying C:\Users\Andres Pineda\AppData\Local\Temp\mono-wasm-dd3c370ef1b\dbg-proxy\netcoreapp3.0\Microsoft.Extensions.Logging.dll -> \\?\C:\develop\uno\misc\Uno-Issue\FrontEnd\FrontEnd.Wasm\obj\Debug\netstandard2.0\wasm-debugger\mono-wasm-dd3c370ef1b\Microsoft.Extensions.Logging.dll
4>Copying C:\Users\Andres Pineda\AppData\Local\Temp\mono-wasm-dd3c370ef1b\dbg-proxy\netcoreapp3.0\Microsoft.Extensions.Options.dll -> \\?\C:\develop\uno\misc\Uno-Issue\FrontEnd\FrontEnd.Wasm\obj\Debug\netstandard2.0\wasm-debugger\mono-wasm-dd3c370ef1b\Microsoft.Extensions.Options.dll
4>Copying C:\Users\Andres Pineda\AppData\Local\Temp\mono-wasm-dd3c370ef1b\dbg-proxy\netcoreapp3.0\Microsoft.Extensions.Primitives.dll -> \\?\C:\develop\uno\misc\Uno-Issue\FrontEnd\FrontEnd.Wasm\obj\Debug\netstandard2.0\wasm-debugger\mono-wasm-dd3c370ef1b\Microsoft.Extensions.Primitives.dll
4>Copying C:\Users\Andres Pineda\AppData\Local\Temp\mono-wasm-dd3c370ef1b\dbg-proxy\netcoreapp3.0\Mono.Cecil.dll -> \\?\C:\develop\uno\misc\Uno-Issue\FrontEnd\FrontEnd.Wasm\obj\Debug\netstandard2.0\wasm-debugger\mono-wasm-dd3c370ef1b\Mono.Cecil.dll
4>Copying C:\Users\Andres Pineda\AppData\Local\Temp\mono-wasm-dd3c370ef1b\dbg-proxy\netcoreapp3.0\Mono.Cecil.Mdb.dll -> \\?\C:\develop\uno\misc\Uno-Issue\FrontEnd\FrontEnd.Wasm\obj\Debug\netstandard2.0\wasm-debugger\mono-wasm-dd3c370ef1b\Mono.Cecil.Mdb.dll
4>Copying C:\Users\Andres Pineda\AppData\Local\Temp\mono-wasm-dd3c370ef1b\dbg-proxy\netcoreapp3.0\Mono.Cecil.Pdb.dll -> \\?\C:\develop\uno\misc\Uno-Issue\FrontEnd\FrontEnd.Wasm\obj\Debug\netstandard2.0\wasm-debugger\mono-wasm-dd3c370ef1b\Mono.Cecil.Pdb.dll
4>Copying C:\Users\Andres Pineda\AppData\Local\Temp\mono-wasm-dd3c370ef1b\dbg-proxy\netcoreapp3.0\Mono.Cecil.Rocks.dll -> \\?\C:\develop\uno\misc\Uno-Issue\FrontEnd\FrontEnd.Wasm\obj\Debug\netstandard2.0\wasm-debugger\mono-wasm-dd3c370ef1b\Mono.Cecil.Rocks.dll
4>Copying C:\Users\Andres Pineda\AppData\Local\Temp\mono-wasm-dd3c370ef1b\dbg-proxy\netcoreapp3.0\Mono.WebAssembly.DebuggerProxy.dll -> \\?\C:\develop\uno\misc\Uno-Issue\FrontEnd\FrontEnd.Wasm\obj\Debug\netstandard2.0\wasm-debugger\mono-wasm-dd3c370ef1b\Mono.WebAssembly.DebuggerProxy.dll
4>Copying C:\Users\Andres Pineda\AppData\Local\Temp\mono-wasm-dd3c370ef1b\dbg-proxy\netcoreapp3.0\Mono.WebAssembly.DebuggerProxy.pdb -> \\?\C:\develop\uno\misc\Uno-Issue\FrontEnd\FrontEnd.Wasm\obj\Debug\netstandard2.0\wasm-debugger\mono-wasm-dd3c370ef1b\Mono.WebAssembly.DebuggerProxy.pdb
4>Copying C:\Users\Andres Pineda\AppData\Local\Temp\mono-wasm-dd3c370ef1b\dbg-proxy\netcoreapp3.0\Newtonsoft.Json.dll -> \\?\C:\develop\uno\misc\Uno-Issue\FrontEnd\FrontEnd.Wasm\obj\Debug\netstandard2.0\wasm-debugger\mono-wasm-dd3c370ef1b\Newtonsoft.Json.dll
4>Copying C:\Users\Andres Pineda\AppData\Local\Temp\mono-wasm-dd3c370ef1b\dbg-proxy\netcoreapp3.0\ProxyDriver -> \\?\C:\develop\uno\misc\Uno-Issue\FrontEnd\FrontEnd.Wasm\obj\Debug\netstandard2.0\wasm-debugger\mono-wasm-dd3c370ef1b\ProxyDriver
4>Copying C:\Users\Andres Pineda\AppData\Local\Temp\mono-wasm-dd3c370ef1b\dbg-proxy\netcoreapp3.0\ProxyDriver.deps.json -> \\?\C:\develop\uno\misc\Uno-Issue\FrontEnd\FrontEnd.Wasm\obj\Debug\netstandard2.0\wasm-debugger\mono-wasm-dd3c370ef1b\ProxyDriver.deps.json
4>Copying C:\Users\Andres Pineda\AppData\Local\Temp\mono-wasm-dd3c370ef1b\dbg-proxy\netcoreapp3.0\ProxyDriver.dll -> \\?\C:\develop\uno\misc\Uno-Issue\FrontEnd\FrontEnd.Wasm\obj\Debug\netstandard2.0\wasm-debugger\mono-wasm-dd3c370ef1b\ProxyDriver.dll
4>Copying C:\Users\Andres Pineda\AppData\Local\Temp\mono-wasm-dd3c370ef1b\dbg-proxy\netcoreapp3.0\ProxyDriver.pdb -> \\?\C:\develop\uno\misc\Uno-Issue\FrontEnd\FrontEnd.Wasm\obj\Debug\netstandard2.0\wasm-debugger\mono-wasm-dd3c370ef1b\ProxyDriver.pdb
4>Copying C:\Users\Andres Pineda\AppData\Local\Temp\mono-wasm-dd3c370ef1b\dbg-proxy\netcoreapp3.0\ProxyDriver.runtimeconfig.dev.json -> \\?\C:\develop\uno\misc\Uno-Issue\FrontEnd\FrontEnd.Wasm\obj\Debug\netstandard2.0\wasm-debugger\mono-wasm-dd3c370ef1b\ProxyDriver.runtimeconfig.dev.json
4>Copying C:\Users\Andres Pineda\AppData\Local\Temp\mono-wasm-dd3c370ef1b\dbg-proxy\netcoreapp3.0\ProxyDriver.runtimeconfig.json -> \\?\C:\develop\uno\misc\Uno-Issue\FrontEnd\FrontEnd.Wasm\obj\Debug\netstandard2.0\wasm-debugger\mono-wasm-dd3c370ef1b\ProxyDriver.runtimeconfig.json
4>Copying C:\Users\Andres Pineda\AppData\Local\Temp\mono-wasm-dd3c370ef1b\dbg-proxy\netcoreapp3.0\System.ComponentModel.Annotations.dll -> \\?\C:\develop\uno\misc\Uno-Issue\FrontEnd\FrontEnd.Wasm\obj\Debug\netstandard2.0\wasm-debugger\mono-wasm-dd3c370ef1b\System.ComponentModel.Annotations.dll
4>Copying C:\Users\Andres Pineda\AppData\Local\Temp\mono-wasm-dd3c370ef1b\dbg-proxy\netcoreapp3.0\System.Runtime.CompilerServices.Unsafe.dll -> \\?\C:\develop\uno\misc\Uno-Issue\FrontEnd\FrontEnd.Wasm\obj\Debug\netstandard2.0\wasm-debugger\mono-wasm-dd3c370ef1b\System.Runtime.CompilerServices.Unsafe.dll
4>Done building project "FrontEnd.Wasm.csproj".
========== Rebuild All: 2 succeeded, 0 failed, 3 skipped ==========

I want you to try a couple of things on your side:

• First, try selecting [Build Only] from the dropdown at the Error Pad. This is to validate that the errors you are seeing are actually build-errors or not.

• What happens if you select another target that is not Android?

• Let's try cleaning the Solution and do a Rebuild.

• Manually deleting the obj, bin, and the .vs directories. The .vs is a hidden directory in the root solution directory.
  

• One thing that works for me when I am dealing with inexplicable errors like this one is doing a git clean. On the command line or Terminal run a git clean -dfx. This will delete the obj and bin directories plus it will also delete de .vs directory. Note: if you have work in progress you might want to stage it + commit first.

Hope any of this could help you, but if you are still running into issues just update this so we can check on it.

[SetTrend]

Thank you, @ajpinedam, for taking the time.

I followed your steps, but to no avail.

To give a better impression of what's happening I created a screencast of me creating a Uno Platform app solution in Visual Studio 2019:

Does my "offline Live Share" shed some light on the issue?

Perhaps you want to perform a Live Share session?

[SetTrend]

Probably my Visual Studio 2019 settings may give some more details on this issue:

Exported-2020-08-28.zip

Just import my Visual Studio 2019 settings (Visual Studio 2019: Tools > Import and Export Settings ... > Import selected environment settings > Yes, save my current settings > Browse > select my file > Finish)

The _"Yes, save my current settings"_ option saves your settings to disk for backup. After analyzing this issue you can simply import your settings back again and everything is just like before.

[francoistanguay]

It looks like your Active Configuration doesn't rebuild all projects (3 skipped). Can you make sure to either remove projects you can't build from the solution or change configuration to rebuild them all (or rebuild all heads manually, one at the time)?

[SetTrend]

Hi @francoistanguay, I rebuilt all the projects in the solution, both by Configuration Manager and manually, but to no avail.

For the sake for comprehensiveness and reproducibility I created a screencast of the build session, in case this may shed some light on the issue:

[jeromelaban]

Thanks for the update. Could you provide the full list of the errors in a text file? It looks like specific issue with the android project. Does the count go down if you unload the android project ?

In many cases, though, the tasks view is not useable as it does not respect the same build settings as the actual build process, and it's better to rely on the output window.

[SetTrend]

Thanks, @jeromelaban,

yes, you're right, all the errors are coming from the Android project. When I unload the project, no errors are listed.

Please find the error list in the following attachment:

Uno Errors.zip

In attached ZIP file I also copied the data into an MS Excel file for easier sorting, filtering and other data aggregation.

Which "tasks view" are you referring to?

Am I the only one getting all these errors? You all have zero errors and warnings? So, you cannot reproduce this situation on your machines?

[jeromelaban]

Thanks for the logs. This issue is caused by the Xamarin.Android resource generator, which for some reason is incorrectly considering two files, or two definitions of the same file.

I'm wondering if this could be caused by the fact that there's space in your project's path. Could you try with a path without a space ?

Also, could you try removing this line:
https://github.com/unoplatform/uno/blob/1881ee67e732c12875c6d3662fe135282fb6adbb/src/SolutionTemplate/UnoSolutionTemplate/Droid/UnoQuickStart.Droid.csproj#L16
from your android csproj file ?

About the tasks view, this is the window that show all the errors, which aggregates both intellisense and actual build messages.

[SetTrend]

I tried both, but no change, I'm afraid.

I could clone my VM and we can have a Life Share session, if you like, so you can see and check for yourself. I believe it would be more efficient if you checked things yourself, rather than asking me to play _I spy with my little eye_.

What do you think?

I may be available as of approx. 11 p.m. CEST if that'd be a time that'd be comfortable for you?

[jeromelaban]

Thanks for the update, this is caused by a Xamarin.Android issue for the Resource.Designer.cs.

A workaround can be added as follows, at the end of the android csproj file:

<Project ...>
     ...
    <Target Name="Issue3897Workaround" 
        Condition=" '$(ManagedDesignTimeBuild)' == 'True' "
        AfterTargets="_RemoveLegacyDesigner">
        <!-- https://github.com/unoplatform/uno/issues/3897 -->
        <ItemGroup>
            <Compile Remove="$(_AndroidResourceDesignerFile)"/>
        </ItemGroup>
    </Target>
</Project>

We'll update the Uno templates to include this workaround.

[SetTrend]

Thanks so much for dealing with this issue! 👍👍👍

The plethora of errors are gone now.

However, there are still 2 errors and 7 warnings left in the template:

(Two of the warnings are in conjunction with me not having a Mac connected but about to build an iOS front-end. I take these two warnings as correctly raised.)

Would you want to keep this situation within this issue or would you want me to raise another issue on the remaining template errors?

[jeromelaban]

Those two errors are this time expected (tied to a VS issue), and if you unload/reload the project after the build has been successful, the errors will disappear.

[SetTrend]

@jeromelaban:

On my machine, whatever I do, the errors won't disappear.

Neither ...

• restarting Visual Studio 2019
• rebuilding the Solution within Visual Studio 2019
• unloading and reloading the the projects in the solution

... seems to get rid of the errors

I can see there are InitializeComponent() function definitions available in the MacOS project (the one that's causing the errors):

I'm not familiar with the VS build system. Do you believe the VS issue you mentioned in your previous post will solve this issue? Or is this probably Uno related, though?

… and what about the warnings? How to get rid of these? Why are there binding issues in a blank template?

[jeromelaban]

Thanks. You'll notice that the project that exhibits these errors is the macOS project. For these errors do disappear, all project shave to be rebuilt.

For the warnings, many are related to the way Xamarin interacts with more recent builds of VS, and may be related to Xamarin specifically, which will be again resolved by .NET 5.

Your best bet here is still to use the output window and the result of the build, not the "errors window".

[SetTrend]

Thank you for your extensive help.

After restarting Windows and starting Visual Studio 2019 again, now the errors are gone.

As you can see from the screencast I posted along with my previous message, I actually built the MacOS project:

Maybe the restart requirement has got to do with #3915. Anyway, the errors are gone now 😌

During my development cycle, I'm actually making heavy use of the messages in the Tasks window. Some VS Solution policies of my clients even require an empty Tasks list for production (e.g. "Treat warnings as errors" for Release builds).

[jeromelaban]

Thanks for the update. I agree that warnings should not be there, though the ones that are there are not compiler warnings but msbuild warnings, which generally don't fail in that "warnings as errors" category.