unable to call JNI methods from framework services - android-ndk

I am trying to develop framework service and manager (xManager and xService ) and jni methods which actually the HAL layer. Here i am facing some issue and unable to call jni methods implemented in .cpp and those are calling from xService -- both are in framework related only but in vendor/xxx/utilities/.
How to link jni methods from .cpp to xservice.java.
xService.java -- is having jni methods function declaration and the implementation is xx.cpp in jni folder.
Could please help me here.

Related

Win8 app CLI library integration issue

I have a Win8 app that is purely native (c++) and I've already used a library that is written using managed code AFAIK. No issues there, I created objects and addressed them using C++/CX with ref counted pointers etc.
I need to add a new library, I referenced it as I did previously, but when I declare and object and try to address it I get:
error C3624: 'System::Object': use of this type requires a reference to assembly 'mscorlib'
Using #using <mscorlib.dll> is not a solution obviously, because WinRT does not support #using of a managed assembly.
When I look up the definition of the class I'm using in Object Browser I see that it's inherited from System::Object. The previous library had a class that was inherited from Platform::Object which is valid for C++/CX.
I already contacted the developers of current library I'm trying to use, but it takes a lot of time for them to respond.
Can I work around this issue? What are the possible courses of action?
UPD: Can I ask the developers to rebuild a library for C++/CX?
I do not believe this is going to work in the general case, unless the C# library is a PCL (portable class library). If it leverages anything that is not in the WinRT .NET client profile, it simply will not work.
If it is a PCL, what you can do is write a C# Windows Runtime Component that itself has a reference to this third-party library and wraps the necessary functionality. Then you reference that C# Windows Runtime Component from your C++/Cx application.

ReactiveUI: getting thread marshaling errors when using with Portable Class Libraries

Say you have:
Portable Class Library where you have most of your ViewModel code
You are using reactive-ui in that class library (and thus have nuget reactiveui-core in there)
What can be the source of thread marshalling errors (e.g. The application called an interface that was marshalled for a different thread. (Exception from HRESULT: 0x8001010E (RPC_E_WRONG_THREAD)))?
While you have included the nuget package reactiveui-core, perhaps, in your main application, you need to also include the "reactiveui" nuget package. This package can't be used in a PCL, but it must be included in your main application. Without it, the platform specific code that fills RxApp and other platform-specific items in the library will not work. Unfortunately, in reactiveui, this is a silent failure. And you can chase your tail for a few hours before figuring this out. :-)
This was discovered in the reactiveui v6 beta.

MvvmCross registering interfaces using IoC in Xamarin iOS7 and XCode 5

I'm having an issue activating the IMvxMessenger using IoC. (Mac, Xamarin Studio, iOS7, Mono 3.2)
I have downloaded NPlus1DaysOfMvvmCross and loaded the N37 Maps project.
Compiled the project and it works fine.
I then added the Cirrious.MvvmCross.Plugins.Messenger.dll to the project and the following code to the app.cs Initialize just below the service IoC call.
CreatableTypes (typeof(IMvxMessenger).Assembly).AsInterfaces ().RegisterAsSingleton ();
I receive and error when compiling that says:
Failed to resolve parameter for parameter id of type Guid when creating Cirrious.MvvmCross.Plugins.Messenger.MvxSubscriptionToken
IMvxMessenger is a plugin and does not need to be registered for IoC in the way you are doing it. Plugins get registered by creating a bootstrap class for each of the plugins you want to use in your project like so:
public class MessengerPluginBootstrap
: MvxPluginBootstrapAction<Cirrious.MvvmCross.Plugins.Messenger.PluginLoader>
{
}
Some plugins with platform dependent parts, such as the Visibility Plugin, need to be registered in a different manner on iOS, because it is silly:
public class VisibilityPluginBootstrap
: MvxLoaderPluginBootstrapAction<Cirrious.MvvmCross.Plugins.Visibility.PluginLoader, Cirrious.MvvmCross.Plugins.Visibility.Touch.Plugin>
{
}
This way you should be able to use the types inside of the Plugin using IoC.
This doesn't sound like it's anything to do with ios7
The line of code
CreatableTypes(typeof(IMvxMessenger).Assembly)
.AsInterfaces()
.RegisterAsSingleton ();
will:
take all the creatable types in the assembly (ie any non-abstract types with a public constructor)
will then find their interfaces
will then create a new instance and register that as the singleton implementation for the interfaces.
For the Messenger plugin, that includes trying to new and register an MvxSubscriptionToken as an IDisposable singleton - although this fails as the public constructor for MvxSubscriptionToken requires a Guid (and you haven't told MvvmCross how to supply that - so the construction fails)
If you did want to just register specific types in an Assembly, then normally you'd add a EndingWith("PostFix") clause - like the default Mvx nuget templates do with Services as the postfix.
If you did want to just register a single specific class from an Assembly, then you'd often just do that as:
Mvx.RegisterSingleton<IThing>(new Thing());
However, for plugins - which are just a convention-based set of rules placed on top of IoC - what you normally want to do is to call EnsureLoaded() on the plugin manager for the PluginLoader for that plugin.
The easiest way to do that is to include a Bootstrap file in the UI project - see the examples in N=8 - https://github.com/slodge/NPlus1DaysOfMvvmCross/tree/master/N-09-Location%20And%20Message/Location.Touch/Bootstrap - your application's Setup will use Reflection to find that Type and will then call EnsureLoaded on the plugin for you.
For more on IoC in MvvmCross, see https://github.com/slodge/MvvmCross/wiki/Service-Location-and-Inversion-of-Control
For more on plugins, see https://github.com/slodge/MvvmCross/wiki/MvvmCross-plugins
Make sure the plugin is installed in the Core project AND the Android project.

BaseTypeAttribute not found in a binding project

I'm trying to create Xamarin bindings for a Obj-C library. I'm following the provided guide from http://docs.xamarin.com/guides/ios/advanced_topics/binding_objective-c_libraries
Everything goes well, OBjective Sharpie creates the interfaces and no error is reported. It is only when I try to compile the solution that the [BaseType] (BaseTypeAttribute class) is not found.
Does anybody knows what I'm missing?
Where is the BaseTypeAttribute class defined?
Thank,
Ignacio
API definition files are compiled using the btouch tool, not a C# compiler. The btouch tool compiles your API definition against itself, where the type is defined.
The project was not compiling as I added the output of Sharpie to a new file.
You either use the provided ApiDefinition file or you have to set the Build Action to ObjCBindingApiDefinition

Using Protobuf-Net In Xamarin.iOS without full AOT

Is there any alternative to achieving serialising and deserialising of objects in Xamarin.iOS (Monotouch) using protobuf-net other than this method:
http://www.frictionpointstudios.com/blog/2011/3/31/using-protobuf-net-serialization-in-unity-iphone.html
Reading around some people claim they have managed it (without giving evidence), but my understanding is that [iOS JIT==NO] so does not quite make sense.
If the only possible solution is to fully AOT all relevant classes what might a suitable pre/post-build event command line be to perform this AOT for any relevant assemblies automatically?
I've heard a good number of people have success via that route, but I too can't give documented evidence.
That method is a bit out of date - I've simplified a few steps; there is a standalone pre-compile tool that should work:
create a project/assembly for the DTOs that you want to serialize that references the appropriate version of protobuf-net; presumably CoreOnly/ios, ideally with that dll set to copy into the output directory (it just makes life easier)
run
precompile "SomePath/YourDto.dll" -t:MySerializer -o:MySerializer.dll
(maybe with a mono before that to get mono to host the exe)
this should resolve the framework and compile a MySerializer.dll that you can reference, which involves zero JIT (MySerializer.dll will reference your dto dll and the version of protobuf-net that your dto dll referenced)
now reference your dto dll, the serializer dll, and the protobuf-net dll, and it should all work just by using new MySerializer().Serialize(...)
when you compile your solution, the projects should all AOT nicely
I'll be happy to offer guidance, but currently I am mac-less, so I can't check right now. If you get any problems let me know. If it can't resolve the framework, you can add -f:{path to the framework assemblies} to give it a clue.
I got protobuf-net 2 working on Xamarin-iOS by using the netstandard1.0 dll. You can get this dll by extracting the nuget package. No changes were needed.

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