Error CS0246: The type or namespace name 'MauiUIApplicationDelegate' could not be found (are you missing a using directive or an assembly reference?)

Question

Hi i am all of sudden getting this error message in my MAUI project after upgrading Visual Studio Mac.... How to fix it? Error CS0246: The type or namespace name 'MauiUIApplicationDelegate' could not be found (are you missing a using directive or an assembly reference?)

Visual Studio Mac 17.6.9 build 415 Runtime .NET 7.0.3 (64-bit) .NET SDK (Arm64) SDK: /usr/local/share/dotnet/sdk/8.0.100-rc.2.23502.2/Sdks SDK Versions: 8.0.100-rc.2.23502.2 Apple Developer Tools Xcode: 15.1 22502 Build: 15C65 Xamarin.iOS Version: 16.4.0.23 Visual Studio Community Hash: 9defd91b3 Branch: xcode14.3 Build date: 2023-10-23 16:15:00-0400 Xamarin Designer Version: 17.6.3.9 Hash: 2648399ae8 Branch: remotes/origin/d17-6 Build date: 2024-02-07 03:23:12 UTC Xamarin.Android Version: 13.2.2.0 (Visual Studio Community)

Answer 1

As visual studio for Mac is retired, support stops at .net 7. Using .net 8 sdk is unsupported, and you may run into issues.

Answer 2

Hi folks for anyone that comes across this error, i found this was due to a bug in 8.0.200. a new version has been been released so if you use that one or an earlier one hopefully the error goes away.

Answer 3

I had the same problem in my case, I had not uninstalled the workloads from version 8.0.100 and this was generating a conflict.