Xamarin IOS Error Native linking failed when Build - xamarin

I run Project from visual studio 2022 on windows, when run on simulator run well but when build on iphone I found errors
I try to update all nugget but not working ,Linker behavior :Link Framework sdks only ,supported architecture:Armv7+Arm64 ,Deployment traget:9.0

According to the error message you provided, there are two reasons.
For Native linking failed, undefined Objective-C class: You can add the [Protocol] attribute to the api that binds the Objective-C protocol for annotation, you can refer to the official Xamarin.iOS documentation.
For Native linking failed, undefined symbol: A third-party binding requires a framework, but the binding does not specify this in its [LinkWith] attribute, you should modify the binding's [LinkWith] attribute, you can refer to the official Xamarin.iOS documentation for details.

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Using custom .dll file produces Unable to resolve reference 'Windows.Foundation.UniversalApiContract' and other errors

I'm currently developing a Unity app for the Hololens 2. Here I want to send data to the Hololens through Bluetooth. To do this I have made a small Bluetooth library and compiled this into a .dll file. I then tried to import this .dll file into my assets, but multiple errors occur:
Unable to resolve reference 'Windows.Foundation.UniversalApiContract'. Is the assembly missing or incompatible with the current platform?
Reference validation can be disabled in the Plugin Inspector.
Unable to resolve reference 'Windows.Foundation.FoundationContract'. Is the assembly missing or incompatible with the current platform?
Reference validation can be disabled in the Plugin Inspector.
Unable to resolve reference 'System.Runtime.WindowsRuntime'. Is the assembly missing or incompatible with the current platform?
Reference validation can be disabled in the Plugin Inspector.
I have updated the SDK version and have targeted the newest all around, but the error persists.
This happens because the WinRT API is only available when building to Universal Windows Platform, and it’s not available in Unity Editor. When using the API from Windows Runtime, it’s advisable to conditionally include any WinRT-leveraged code with preprocessor directive ENABLE_WINMD_SUPPORT define.
For more information about how to make use of WinRT APIs in your Unity project for HoloLens please refer to here: WinRT APIs with Unity for HoloLens

WebUI Deprecated mail even after the following the steps mentioned in Xamarin forum

Recently we have been receiving the UIWebView deprecated warnings from Appstore, for which xamarin forms has directed the developers to do the below four things
Update Xamarin.Forms to 4.5 or higher – Pre-release versions of Xamarin.Forms 4.5 can be used.
Use Xamarin.iOS 13.10.0.17 or higher – Check your Xamarin.iOS version in Visual Studio. This version of Xamarin.iOS is included with Visual Studio for Mac 8.4.1 and Visual Studio 16.4.3.
Remove references to UIWebView – Your code should not have any references to UIWebView or any classes that make use of UIWebView.
And add the additional mtouch argument ‘--optimize=experimental-xforms-product-type’
But even after doing all those things we are still getting the warning mail form apple.
We are using a third part package which is using the older Xamarin.Forms component Whether this may be the cause of the warning mail?
I'm afraid it's the Xamarin.Forms version
I saw someone faced the issue here but he consumed some third-party libraries:
https://forums.xamarin.com/discussion/comment/404242
It works after removing the Calabash.
Moreover, we need to change the linker behavior to make the linker remove the UIWebView part. Please refer to this blog for more information:
https://devblogs.microsoft.com/xamarin/uiwebview-deprecation-xamarin-forms/

Getting an error while using Microsoft.AppCenter with Xamarin.iOS

I am trying to use Microsoft.AppCenter nuget to a Xamarin app. Xamarin.Android is building fine. But I am getting an error while trying to build the Xamarin.iOS app.
MTOUCH: Error MT5210: Native linking failed, undefined symbol: _kMSLongTypedPropertyType. Please verify that all the necessary frameworks have been referenced and native libraries are properly linked in.
I have tried the solution mentioned in the below link
https://learn.microsoft.com/en-us/xamarin/ios/troubleshooting/mtouch-errors#MT5210
But I am still getting the error while I am trying to build Xamarin.iOS app. I am using the below configurations:
Visual Studio Community 2019 for Mac
Version 8.4.4 (build 91)
Xamarin.iOS
Version: 13.10.0.17 (Visual Studio Community)
The issue got fixed after installing Microsoft.AppCenter.Analytics and Microsoft.AppCenter.Crashes. As #Junior Jiang - MSFT mentioned, if code uses microsoft app center to get the analytics and crashes, we need to install these two nugets along with Microsoft.AppCenter. Thanks.

Why does adding the Moq NuGet package generate a MT0109 warning

I've started working on a vanilla Xamarin.Forms project, and I get the below warning when trying to build the iOS project, straight after adding Moq to the Forms project.
MTOUCH : warning MT0109: The assembly 'System.Diagnostics.TraceSource.dll' was loaded from a different path than the provided path (provided path: /Users/{me}/.nuget/packages/system.diagnostics.tracesource/4.3.0/runtimes/win/lib/netstandard1.3/System.Diagnostics.TraceSource.dll, actual path: /Library/Frameworks/Xamarin.iOS.framework/Versions/12.8.0.0/lib/mono/Xamarin.iOS/Facades/System.Diagnostics.TraceSource.dll).
There are no warnings reported when adding the NuGet package itself, only when building the iOS project. In fact, there were two warnings when building but I managed to fix one.
I've tried with various versions of Moq (4.7.x, 4.8.x, 4.9.x, 4.10.x). Same issue.
I've Googled extensively but it hasn't been much help. I came across the following threads which provided some insight but didn't actually help solve the issue:
How do I get rid of these compiler warnings about wrong paths
https://developercommunity.visualstudio.com/content/problem/121551/xamarin-ios-build-assembly-path-mismatch.html
https://github.com/dotnet/standard/issues/481
Questions: How can I resolve this warning? Is this an issue with Moq that needs a bug repro submitted?
My environment:
VS for Mac 2019 V8.0.4 (build 0)
Xamarin.Forms project uses
Xamarin.Forms 3.6.0.x, Xamarin.Essentials 1.0.1, Moq (causing the
warning), and the target framework is .NET Standard 2.0.

Failed to resolve assembly "Xamarin.Forms.Platform.iOS" error after adding Xamarin Forms Labs

I added Xamarin Forms Labs 1.2.O from NuGet to the iOS project. The same project also references Xamarin Forms dll, v1.3.0.6292.
After adding the Xamarin labs reference and updating AppDelegate to inherit from XFormsApplicationDelegate, I keep getting this compile time error:
MTOUCHTASK: error MT2002: Failed to resolve assembly: 'Xamarin.Forms.Platform.iOS, Version=1.2.3.0 ...
How do I resolve this issue?
When using Xamarin.Forms 1.3 you needed to update to the latest pre-release of Xamarin.Labs which is Xamarin.Forms.Labs 1.2.1-pre2.
Try updating to that to see if it works.

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