I'm new in Xamarin, Xamarin.Forms and C# platform.
I'm starting the development of an app that should support Android and iOS devices. I'm using a PCL project for code sharing. Currently this project is using the profile111 because Visual Studio has selected it by default for me. But when I try to install some NuGet packages I'm getting a message saying the package is not compatible. Something like:
Could not install package 'DocsBrStandard 2.0.1'. You are trying to
install this package into a project that targets
'.NETPortable,Version=v4.5,Profile=Profile111', but the package does
not contain any assembly references or content files that are
compatible with that framework.
I believe this message is related with the profile I'm using, right?
So which profile should I use for my app that should support only iOS and Android devices? Is profile111 the more appropriate for this scenario?
At least, how can I identify if a package is compatible or not with my Xamarin.Forms app?
Thanks.
You need to target .NET Standard to be able to use the DocsBrStandard package. So you can't work with profile based PCL if you want to use that package.
Check out this article about targeting .NET Standard with Xamarin.Forms:
https://blog.xamarin.com/building-xamarin-forms-apps-net-standard/
Related
I recently started to develop android apps with Xamarin for Visual studio, but every time I want to install a Nuget package for C#.Net I get this error Message:
The package "System.Reflection.Extensions 4.0.0" couldn't be installed. You try to install the package into a project, which refers to MonoAndroid,Version=v7.1", the package doesn't contain assemblyreferences or contentfiles, which are compatible with this framework. Contact the Autor of the nuget package for more information.
Is there any way to modify the nugetpackage to match my needs or do I really have to contact the author of the package?
You can't install the Overwatch.Net package because it only targets .NET 4.5.2 and does not contain libraries for either PCL or Xamarin.Android.
Looking at the code for the library, there is no reason it could not be a PCL, so you have 2 options.
Ask the author of Overwatch.NET to make a PCL or NETStandard version of the library
Do the work yourself and convert it
So I am currently trying to install Win2D.win81 as a NuGet package via VS2015s package manager. My goal is to rewrite a simple graphing library I made to now work with a WPF control instead of winforms and benefit from the performance of Win2D vs GDI+.
To do that I made a new ClassLibrary project and added a userControl (WPF). Now I am trying to add Win2D via the package manger to the project but it keeps rejecting telling me the package doesn't target my target framework. Which wasn't that big of a deal if I haven't tried setting my project to target .Net 3.5 to 4.6.2 and any version in between and it always kept rejecting to install.
Excat error from PM:
Could not install package 'Win2D.win81 1.20.0'. You are trying to install this package into a project that targets '.NETFramework,Version=v4.6', but the package does not contain any assembly references or content files that are compatible with that framework.
Win2D.win81 targets Windows 8.1 Store and Windows Phone 8.1 apps, which is a separate .net framework from the full .net 4.6 framework that you are trying to use.
When trying to install the netmq vis nuget, I get the following error:
Could not install package 'AsyncIO 0.1.18'. You are trying to install this package
into a project that targets '.NETPortable,Version=v4.5,Profile=Profile111',
but the package does not contain any assembly references or content files that
are compatible with that framework. For more information, contact the package author.
The problem is that netmq depends on AsyncIO. when installing it, nuget find that the assembly is not compatible with .Net 4.5.
so nuget fail in installing AsyncIO, and then failed in installing netmq.
So I downloaded the AsyncIO Source from Github and build it locally with .Net 4.5.
After that and added the dll of AsyncIO built locally as a reference for my project.
Theoretically, NetMQ should be successfully installed with nuget. because I added the needed reference to AsyncIO.
But when trying to reinstall NetMQ, I get the same error:
Could not install package 'AsyncIO 0.1.18'. You are trying to install this package
into a project that targets '.NETPortable,Version=v4.5,Profile=Profile111',
but the package does not contain any assembly references or content files that
are compatible with that framework. For more information, contact the package author.
and nuget did not detect that I added 'AsyncIO 0.1.18' in my project.
How to let nuget detect that I added this reference in my project?
Have a look here:
.NET Portable profiles
Profile111 is a combination of:
.NET Framework 4.5
Windows 8.0
Windows Phone 8.1
or in other words:
portable-net45+netcore45+wpa81
So your project into which you are trying to append the NuGet targets Windows Phone 8.1 and other 2 platforms, I mention this one as the most restrictive.
Now let's have a look at the named NuGet package's source:
<ProjectGuid>{3830B7A3-0225-4FDA-B155-E085E183650C}</ProjectGuid>
<OutputType>Library</OutputType>
<TargetFrameworkVersion>v4.0</TargetFrameworkVersion>
<TargetFrameworkProfile>
</TargetFrameworkProfile>
What do we have here? We can see that the project is not a PCL. It is targeting full .NET 4.0 framework which is not available on Windows Phone 8.1. And your library does target Windows Phone 8.1. See the problem?
You say that if you compile the AsyncIO targeting .NET 4.5 than you can successfully append it into your project as a reference? That's not altogether true. I mean you can append a reference to it but you cannot use it. You will see that when you try to call something from that reference.
In order to use AsyncIO from you PCL will have to build AsyncIO as a PCL targeting the same or more restrictive set of platforms. Try creating a PCL project targeting Profile111 and try compiling the AsyncIO code with it (just link the original AsyncIO source files (*.cs) into this new AsyncIO_PCL project). If you are lucky enough and the code of AsyncIO is really compatible you will be able to use that library.
Here are your steps:
Create a new project (named AsyncIO_PCL) of type PCL class library.
Pick the Profile111 platform set i.e.
.NET Framework 4.5
Windows 8.0
Windows Phone 8.1
Link all the .cs files from the original AsyncIO project save one (AssemblyInfo.cs) into the new AsyncIO_PCL project.
Set the output assembly name to the same as in original AsyncIO project.
Try building the project.
Your ability to build the AsyncIO as a PCL with the required set of supported platforms depends on AsyncIO code i.e. which API is used inside and if that API is supported by all the three platforms you are targeting.
Try clicking right-button on the project -> Properties. In the "Application" menu check the "Target Framework". It should be set to .NET Framework 4.5
I have tried adding the Signalr Client library and the WebApi client package to my Xamarin Solution (on Visual Studio with Xamarin Support and also on Xamarin Studio) but I always get this error although I am able to install other PCLs (for example Microsoft.Net.Http):
Could not install package 'Microsoft.AspNet.WebApi.Client 5.2.3'. You are trying to install this package into a project that targets 'portable-net45+sl50+win+wpa81+wp80+MonoAndroid10+xamarinios10+MonoTouch10', but the package does not contain any assembly references or content files that are compatible with that framework. For more information, contact the package author.
and the following error when adding Signalr:
Adding Microsoft.AspNet.SignalR.Client...
Adding 'Microsoft.AspNet.SignalR.Client 2.2.0' to Corda.Client.
Could not install package 'Microsoft.AspNet.SignalR.Client 2.2.0'. You are trying to install this package into a project that targets 'portable-net45+sl50+win+wpa81+wp80+MonoAndroid10+xamarinios10+MonoTouch10', but the package does not contain any assembly references or content files that are compatible with that framework. For more information, contact the package author.
I have also tried changing the the target framework with not success.
This is the build setting for my project:
and this is my C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework.NETPortable\v4.5\Profile\Profile259\SupportedFrameworks folder:
I get the same errors on both Mac OSX and Windows 10. Any ideas?
Using Profile78 solved my problem. Full explaination here.
A simple workaround that worked with my Xamarin with VS:
Download the dll-files manually here: https://components.xamarin.com/gettingstarted/signalr/true
Import the following into your solution.
Microsoft.AspNet.SignalR.Client.dll
Newtonsoft.Json.dll
System.Net.Http.Extensions.dll
System.Net.Http.Primitives.dll
Done!
The problem is not with the dll-files, but with the (nuget) installer.
The problem is with the nuget package manager,specifically with the Windows Phone 8.1 project. I think it expects it to be a windows phone silverlight 8.1 project. There is a bug on installing signalr client on an universal 8.1 phone project in a xamarin project. It should be sorted out in the next xamarin release. Unselecting windows phone 8.1 in the portable config solves the issue,meaning you will have to take the windows phone 8.1 project out of the xamarin project and your need to create a universal windows 10 project.
Yes, As suggested by others this is the problem from nuget package manager, As per this link it should be fixed with the realease of Microsoft.signalr.client 2.2.1 version but for now if you still want to go with nuget, Add the below nuget source
https://www.myget.org/F/aspnetwebstacknightly/
to visual studio and install pre release version 2.2.1 pre-160523-b816 of the signalr client dll as suggested in below link
https://github.com/SignalR/SignalR/issues/3393
I'm trying to add MvvmCross-SecureStorage plugin of MvvmCross to PCL wich contains classes shared between Universal Widows app iOs apps and Android apps, but I'm getting this kind of error.
Could not install package 'Beezy.MvvmCross.Plugins.SecureStorage 1.0.0'. You are trying to install this package into a project that targets 'portable-net45+win+wpa81+MonoAndroid10+xamarinios10+MonoTouch10', but the package does not contain any assembly references or content files that are compatible with that framework. For more information, contact the package author.
Anybody successfully added this plugin to PCL?
Looking at https://github.com/ChristianRuiz/MvvmCross-SecureStorage it looks like this project doesn't yet support the new unified xamarinios10 target which is included in your list.
One route forwards would be to add unified support to that open source project and to send them a Pull Request.