I installed visual studio extension xamarin the Design is not displayed.
it puts me this: Assembly reference are missing
I have already regenerated the project to restore the cache nuget
someone has a another solution to propose to me?

I have developed a web application that uses a Web Core API to update the on premise SQL Server database.
I now need to develop a Xamarin app that can update this on premise database via Azure.
The decision has been made on the premise that SQL Server on the cloud is too expensive and is a security concern. Also it is easier to setup azure access rather than VPN access.
Now this video partly answers the question:
https://azure.microsoft.com/en-gb/resources/videos/connect-to-on-premises-sql-server-from-mobile-services-using-hybrid-connections/.
But I am wondering how to connect up with a Web Core API which operates on the on-premise SQL Server with Azure Mobile Services?

link of images here: pastebin(dot)com/LNe6c7Wp
Image 1

This is what is showing whenever I try to open Android Device Manager

Image 2,3,4

This is what is installed.

Image 5

This is what is showing when I run it. I dont have any codes as of the moment. Just created a new project.

I am so sorry. I am new to this. Please help me. Thank you.

Also if possible, I would like to run it on my phone. I always do that on Android Studio but I dont know how to do it here. I only know Xamarin Live but it doesnt work for me

I am unable to build and run ios apps in visual studio after updating Visual Studio last week. I get several errors i have not seen before when trying as per below.

Any idea how i can resolve this? I am using the latest xcode and visual studio for Mac on the build host.

Severity Code Description Project File Line Suppression State
Error CS0009 Metadata file 'C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\Common7\IDE\ReferenceAssemblies\Microsoft\Framework\Xamarin.iOS\v1.0\Facades\System.Xml.XDocument.dll' could not be opened -- PE image doesn't contain managed metadata. RiskSolved.Mobile.iOS C:\Users\James\Documents\GitHub\RiskSolved.Mobile\RiskSolved.Mobile\RiskSolved.Mobile.iOS\CSC 1 Active
Error CS0009 Metadata file 'C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\Common7\IDE\ReferenceAssemblies\Microsoft\Framework\Xamarin.iOS\v1.0\Facades\System.Xml.ReaderWriter.dll' could not be opened -- PE image doesn't contain managed metadata. RiskSolved.Mobile.iOS C:\Users\James\Documents\GitHub\RiskSolved.Mobile\RiskSolved.Mobile\RiskSolved.Mobile.iOS\CSC 1 Active
Error CS0009 Metadata file 'C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\Common7\IDE\ReferenceAssemblies\Microsoft\Framework\Xamarin.iOS\v1.0\Facades\System.Diagnostics.TraceSource.dll' could not be opened -- PE image doesn't contain managed metadata. RiskSolved.Mobile.iOS C:\Users\James\Documents\GitHub\RiskSolved.Mobile\RiskSolved.Mobile\RiskSolved.Mobile.iOS\CSC 1 Active
Error CS0009 Metadata file 'C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\Common7\IDE\ReferenceAssemblies\Microsoft\Framework\Xamarin.iOS\v1.0\Facades\System.Diagnostics.TraceEvent.dll' could not be opened -- PE image doesn't contain managed metadata. RiskSolved.Mobile.iOS C:\Users\James\Documents\GitHub\RiskSolved.Mobile\RiskSolved.Mobile\RiskSolved.Mobile.iOS\CSC 1 Active

I am unable to build and run ios apps in visual studio after updating Visual Studio last week. I get several errors i have not seen before when trying as per below.

Any idea how i can resolve this? I am using the latest xcode and visual studio for Mac on the build host.

Severity Code Description Project File Line Suppression State
Error CS0009 Metadata file 'C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\Common7\IDE\ReferenceAssemblies\Microsoft\Framework\Xamarin.iOS\v1.0\Facades\System.Xml.XDocument.dll' could not be opened -- PE image doesn't contain managed metadata. RiskSolved.Mobile.iOS C:\Users\James\Documents\GitHub\RiskSolved.Mobile\RiskSolved.Mobile\RiskSolved.Mobile.iOS\CSC 1 Active
Error CS0009 Metadata file 'C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\Common7\IDE\ReferenceAssemblies\Microsoft\Framework\Xamarin.iOS\v1.0\Facades\System.Xml.ReaderWriter.dll' could not be opened -- PE image doesn't contain managed metadata. RiskSolved.Mobile.iOS C:\Users\James\Documents\GitHub\RiskSolved.Mobile\RiskSolved.Mobile\RiskSolved.Mobile.iOS\CSC 1 Active
Error CS0009 Metadata file 'C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\Common7\IDE\ReferenceAssemblies\Microsoft\Framework\Xamarin.iOS\v1.0\Facades\System.Diagnostics.TraceSource.dll' could not be opened -- PE image doesn't contain managed metadata. RiskSolved.Mobile.iOS C:\Users\James\Documents\GitHub\RiskSolved.Mobile\RiskSolved.Mobile\RiskSolved.Mobile.iOS\CSC 1 Active
Error CS0009 Metadata file 'C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\Common7\IDE\ReferenceAssemblies\Microsoft\Framework\Xamarin.iOS\v1.0\Facades\System.Diagnostics.TraceEvent.dll' could not be opened -- PE image doesn't contain managed metadata. RiskSolved.Mobile.iOS C:\Users\James\Documents\GitHub\RiskSolved.Mobile\RiskSolved.Mobile\RiskSolved.Mobile.iOS\CSC 1 Active

Anyone have any luck with Mac Mohave and Visual Studio for the Mac. I have a 1 year old mac mini that is virtually a boat anchor at this point. Starting up the ios simulator is taking 30 minutes or more.

Hello,

have just started with XamU classes, namely, XAM101 and XAM110 (the basics). Both are fine, but looks bit obsolete, eg. refering to PCL (now deprecated and replaced with .NET Standard) or often talk about Windows Phone (officialy dead for more than a year). These two classes are available for free, just wondering if it is worth paying for the XamU? Are there interesting up-to-date courses, working with VS2017 and .NET Standard?

thanks

Jiri

Hi every one,

I´m using the microcharts library in order to show a chart, but currently I´m getting the following error and I not able to show the chart. Iam using Xamarin Live application on my Android phone. The library that I am using is "microcharts-elegant-cross-platform-charts-for-any-app"

And the error is: Unable to cast object of type 'System.RuntimeType' to type 'Mono.Debugger.Soft.TypeMirror'. I getting the error in the line "var entries= new[]...."

public Chart LastRidesChart
{
get
{
var entries = new[] {
new Entry(212)
{
Label = "UWP",
ValueLabel = "212",
Color = SKColor.Parse("#2c3e50")
},
new Entry(248)
{
Label = "Android",
ValueLabel = "248",
Color = SKColor.Parse("#77d065")
},
new Entry(128)
{
Label = "iOS",
ValueLabel = "128",
Color = SKColor.Parse("#b455b6")
},
new Entry(514)
{
Label = "Shared",
ValueLabel = "514",
Color = SKColor.Parse("#3498db")
} };

            return new PointChart()
            {
                Entries = entries,

            };
        }
    }

Hi Every one,

I am facing problem to send video to server.

Hi, I'm having some trouble trying to figure out why build tools says that app.xaml path on Xamarin Forms is not supported, I can see in the error list window, file column specifically that it's duplicated somewhere, the path shown is repeated and also the warnings say something about preprocessor tokens being duplicated as well, I don't know where do I have to change those values or if there is any workaround for this issue.

Thanks

Testing the Xamarin Apps with free Testing framework

The app has been terminated.
Launch failed. The app 'ChowderApp.iOS' could not be launched on 'iPhone 6s Plus iOS 10.2'. Error: error MT0069: The app directory '/Users/ourweb1/Library/Caches/Xamarin/mtbs/builds/ChowderApp.iOS/a0ba67018c2b1c3f3eab418af7b01492/bin/iPhoneSimulator/Debug/net.ourweb.ChowderApp.app' does not exist.. Please check the logs for more details.
The app has been terminated.

can someone help me

Severity    Code    Description Project File    Line    Suppression State
Warning     The "Xamarin.Forms.Build.Tasks.GetTasksAbi" task could not be loaded from the assembly C:\Users\asiddique\.nuget\packages\xamarin.forms\3.1.0.697729\build\netstandard2.0\Xamarin.Forms.Build.Tasks.dll. Could not load file or assembly 'netstandard, Version=2.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51' or one of its dependencies. The system cannot find the file specified. Confirm that the <UsingTask> declaration is correct, that the assembly and all its dependencies are available, and that the task contains a public class that implements Microsoft.Build.Framework.ITask.  App1.iOS            
Error   CS0246  The type or namespace name 'System' could not be found (are you missing a using directive or an assembly reference?)    App1    c:\users\asiddique\source\repos\App1\App1\App1\MainPage.xaml.cs 1   Active
Error   CS0246  The type or namespace name 'System' could not be found (are you missing a using directive or an assembly reference?)    App1    c:\users\asiddique\source\repos\App1\App1\App1\MainPage.xaml.cs 2   Active
Error   CS0246  The type or namespace name 'System' could not be found (are you missing a using directive or an assembly reference?)    App1    c:\users\asiddique\source\repos\App1\App1\App1\MainPage.xaml.cs 3   Active
Error   CS0246  The type or namespace name 'System' could not be found (are you missing a using directive or an assembly reference?)    App1    c:\users\asiddique\source\repos\App1\App1\App1\MainPage.xaml.cs 4   Active
Error   CS0246  The type or namespace name 'System' could not be found (are you missing a using directive or an assembly reference?)    App1    c:\users\asiddique\source\repos\App1\App1\App1\MainPage.xaml.cs 5   Active
Error   CS0246  The type or namespace name 'Xamarin' could not be found (are you missing a using directive or an assembly reference?)   App1    c:\users\asiddique\source\repos\App1\App1\App1\MainPage.xaml.cs 6   Active
Error   CS0246  The type or namespace name 'ContentPage' could not be found (are you missing a using directive or an assembly reference?)   App1    c:\users\asiddique\source\repos\App1\App1\App1\MainPage.xaml.cs 10  Active
Error   CS0518  Predefined type 'System.Void' is not defined or imported    App1    c:\users\asiddique\source\repos\App1\App1\App1\MainPage.xaml.cs 12  Active
Error   CS0518  Predefined type 'System.Object' is not defined or imported  App1    c:\users\asiddique\source\repos\App1\App1\App1\MainPage.xaml.cs 14  Active
Error   CS0103  The name 'InitializeComponent' does not exist in the current context    App1    c:\users\asiddique\source\repos\App1\App1\App1\MainPage.xaml.cs 14  Active
Error       The "Xamarin.Forms.Build.Tasks.GetTasksAbi" task could not be loaded from the assembly C:\Users\asiddique\.nuget\packages\xamarin.forms\3.1.0.697729\build\netstandard2.0\Xamarin.Forms.Build.Tasks.dll. Could not load file or assembly 'netstandard, Version=2.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51' or one of its dependencies. The system cannot find the file specified. Confirm that the <UsingTask> declaration is correct, that the assembly and all its dependencies are available, and that the task contains a public class that implements Microsoft.Build.Framework.ITask.  App1.Android            
Warning IDE0006 Error encountered while loading the project. Some project features, such as full solution analysis for the failed project and projects that depend on it, have been disabled.   App1.Android        1   Active
Warning     The "Xamarin.Forms.Build.Tasks.XamlCTask" task could not be loaded from the assembly C:\Users\asiddique\.nuget\packages\xamarin.forms\3.1.0.697729\build\netstandard2.0\Xamarin.Forms.Build.Tasks.dll. Could not load file or assembly 'netstandard, Version=2.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51' or one of its dependencies. The system cannot find the file specified. Confirm that the <UsingTask> declaration is correct, that the assembly and all its dependencies are available, and that the task contains a public class that implements Microsoft.Build.Framework.ITask.    App1.UWP            
Warning IDE0006 Error encountered while loading the project. Some project features, such as full solution analysis for the failed project and projects that depend on it, have been disabled.   App1.UWP        1   Active
Warning     Cannot resolve Assembly or Windows Metadata file 'c:\users\asiddique\source\repos\App1\App1\App1\bin\Debug\netstandard2.0\App1.dll' App1.UWP    c:\users\asiddique\source\repos\App1\App1\App1.UWP\App1.UWP.csproj      
Warning IDE0006 Error encountered while loading the project. Some project features, such as full solution analysis for the failed project and projects that depend on it, have been disabled.   App1.iOS        1   Active
Error   MSB4062 The "Xamarin.Forms.Build.Tasks.XamlGTask" task could not be loaded from the assembly C:\Users\asiddique\.nuget\packages\xamarin.forms\3.1.0.697729\build\netstandard2.0\Xamarin.Forms.Build.Tasks.dll. Could not load file or assembly 'netstandard, Version=2.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51' or one of its dependencies. The system cannot find the file specified. Confirm that the <UsingTask> declaration is correct, that the assembly and all its dependencies are available, and that the task contains a public class that implements Microsoft.Build.Framework.ITask.    App1    C:\Users\asiddique\.nuget\packages\xamarin.forms\3.1.0.697729\build\netstandard2.0\Xamarin.Forms.targets    84  
Error   MSB4062 The "Xamarin.Forms.Build.Tasks.GetTasksAbi" task could not be loaded from the assembly C:\Users\asiddique\.nuget\packages\xamarin.forms\3.1.0.697729\build\netstandard2.0\Xamarin.Forms.Build.Tasks.dll. Could not load file or assembly 'netstandard, Version=2.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51' or one of its dependencies. The system cannot find the file specified. Confirm that the <UsingTask> declaration is correct, that the assembly and all its dependencies are available, and that the task contains a public class that implements Microsoft.Build.Framework.ITask.  App1    C:\Users\asiddique\.nuget\packages\xamarin.forms\3.1.0.697729\build\netstandard2.0\Xamarin.Forms.targets    36  

I am compiling my App project in Visual Studio and it throws me the error: Xamarin.Forms.Xaml.XamlParseException: Position 9:10. Type infra: InstanceLocator not found in xmlns clr-namespace: SITApp3.Infrastructure; assembly = SITApp3
Does anyone know how I can solve it?
Thank your contributions

I marked a comment as approved answer mistakenly in one of my post. Can I **UNDO **that action?

if Yes **then **How?

Hello! Looking to connect with a Xamarini MVP/Evangelist for the US/Midwest. Looking to host some developer activities in Louisville, KY for both corporate and individual developers. Please reach out if you either work in this area or know someone in this area I can connect with. Thank you!

Hi,
Access to the path ProjectName\packages\Xamarin.Forms.3.1.0.583944\build\netstandard1.0\Xamarin.Forms.Build.Tasks.dll' is denied.
Access to the path ProjectName\packages\Xamarin.Forms.3.1.0.583944\build\netstandard2.0\Xamarin.Forms.Build.Tasks.dll' is denied.
While Uninstall/Update Xamarin forms am getting this error.
Any one of you aware of this?

I have a dao layer project which deals with sqlite.
When i try to run this project i get following error.

Could not load file or assembly 'Java.Interop' or one of its dependencies. Strong name signature could not be verified. The assembly may have been tampered with, or it was delay signed but not fully signed with the correct private key. (Exception from HRESULT: 0x80131045)

Following is full stack trace

[FileLoadException: Could not load file or assembly 'Java.Interop, Version=0.1.0.0, Culture=neutral, PublicKeyToken=84e04ff9cfb79065' or one of its dependencies. Strong name signature could not be verified. The assembly may have been tampered with, or it was delay signed but not fully signed with the correct private key. (Exception from HRESULT: 0x80131045)]
System.Reflection.RuntimeAssembly._nLoad(AssemblyName fileName, String codeBase, Evidence assemblySecurity, RuntimeAssembly locationHint, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean throwOnFileNotFound, Boolean forIntrospection, Boolean suppressSecurityChecks) +0
System.Reflection.RuntimeAssembly.InternalLoadAssemblyName(AssemblyName assemblyRef, Evidence assemblySecurity, RuntimeAssembly reqAssembly, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean throwOnFileNotFound, Boolean forIntrospection, Boolean suppressSecurityChecks) +457
System.Reflection.RuntimeAssembly.InternalLoad(String assemblyString, Evidence assemblySecurity, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean forIntrospection) +110
System.Reflection.RuntimeAssembly.InternalLoad(String assemblyString, Evidence assemblySecurity, StackCrawlMark& stackMark, Boolean forIntrospection) +22
System.Reflection.Assembly.Load(String assemblyString) +34
System.Web.Configuration.CompilationSection.LoadAssemblyHelper(String assemblyName, Boolean starDirective)

I am using visual studio 2015, Xamarin.android 7.4.2.21, jdk1.8.0_144, 64 bit window 10.

I didn't get this error.
I believe the monoAndroid framework should take care of this.

I have created a custom renderer(UWP) for ListView which enables drag and drop functionality for listview . But after rearranging the listview the change is not reflected back in the itemsource.

Just in case this saves others some time...

On UWP, during development, to assist with debugging after the app has been closed and then re-started from a notification, I originally included the following code to fire up the debugger:

                        if (!System.Diagnostics.Debugger.IsAttached)
                        {
                            System.Diagnostics.Debugger.Launch();
                        }

That dynamically hooked up the debugger as expected. However, subsequently, the following exceptions were reported in the VS Output window:

Exception thrown at 0x00007FF9287250D8 (KernelBase.dll) in MyApp.UWP.exe: WinRT originate error - 0x80070057 : 'FormsCommandBarStyle.xaml is not a valid absolute URI.'.
Exception thrown at 0x00007FF9287250D8 (KernelBase.dll) in MyApp.UWP.exe: WinRT originate error - 0x80070057 : 'PageControlStyle.xaml is not a valid absolute URI.'.
Exception thrown at 0x00007FF9287250D8 (KernelBase.dll) in MyApp.UWP.exe: WinRT originate error - 0x80070057 : 'FormsProgressBarStyle.xaml is not a valid absolute URI.'.
Exception thrown at 0x00007FF9287250D8 (KernelBase.dll) in MyApp.UWP.exe: WinRT originate error - 0x80070057 : 'FormsTextBoxStyle.xaml is not a valid absolute URI.'.
Exception thrown at 0x00007FF9287250D8 (KernelBase.dll) in MyApp.UWP.exe: WinRT originate error - 0x80070057 : 'AutoSuggestStyle.xaml is not a valid absolute URI.'.
Exception thrown at 0x00007FF9287250D8 (KernelBase.dll) in MyApp.UWP.exe: WinRT originate error - 0x80070057 : 'MasterDetailControlStyle.xaml is not a valid absolute URI.'.
Exception thrown at 0x00007FF9287250D8 (KernelBase.dll) in MyApp.UWP.exe: WinRT originate error - 0x80070057 : 'TabbedPageStyle.xaml is not a valid absolute URI.'.
Exception thrown at 0x00007FF9287250D8 (KernelBase.dll) in MyApp.UWP.exe: WinRT originate error - 0x80070057 : 'SliderStyle.xaml is not a valid absolute URI.'.

After some investigation, I discovered that if XAML is being used the app needs to be debugged in a container, which presumably VS starts automatically when launching an app the usual way from the VS IDE (e.g. using F5). To get the same result when debugging notifications, services etc., don't use the code shown at the top of this post. Instead open the Properties page for the UWP project, select the Debug pane, and then check the option "Do not launch, but debug my code when it starts". Like magic, debugging of notifications, services etc. works effortlessly.

For ref., see https://docs.microsoft.com/en-us/visualstudio/debugger/start-a-debugging-session-for-a-store-app-in-visual-studio-vb-csharp-cpp-and-xaml?view=vs-2017