I am starting to develop a scientific software that I hope I will be able to run on multiple platforms. My plan is to use OpenTK for the rendering of the scientific models and plots. As of the moment I have a prototype that runs on Windows using OpenTK 1.1 libraries from http://www.opentk.com/ (a simpler version just with OpenTK and a more complicated one with OpenTK + WindwosForms). I am trying to port that prototype to Android.
It seems that the syntax using by the Xamarin.Android OpenTK library is nearly identical to the one that I am currently using for Windows (with the only difference that OpenGL -> OpenGL ES and GameWindow -> AndroidGameView) so the porting shouldn't be an issue. However, I was hoping that I could avoid a copy-paste method and get a more permanent solution having a shared OpenTK code between the Windows and the Android version.
I have read trough the Xamarin documentation about the shared vs PCL methods for cross-platform development. However, I still struggle to figure out how to set-up a Visual Studio solution with an Android and Windows project and a shared code that will include OpenTK. Is that even possible and can someone give me an example of how to do it? I did explore an example I found for rendering a rotating cube using OpenTK for a shared Android/iOS project (http://developer.xamarin.com/content/TexturedCubeES30/) but in my case I need to use a different OpenTK library for the Windows and for the Android project.
I also found this Do the Android and iOS versions of OpenTK have the same API? discussion. It is very similar to what I would like to do but in my case I am trying to setup a project for Windows and Android (for now).
Can I use only one OpenTK library (which one?) that is being called from both the Android and the Windows project and what will be the right way to set-up both projects so they share the same OpenTK code. This is the first time I am dealing with writing a cross-platform code so I am a bit lost.
Edit: I was able to get a prototype running using Shared Xamarin project and compiler flags as proposed below. Code was indeed not very pretty at places but I got over 70% code re-usability between the two platforms so it was worth the effort. This is how I used the compiler flags in case someone is looking for the same thing (credit to SKall from the Xamarin forums):
#if __ANDROID__
using OpenTK.Graphics.ES11;
#else
using OpenTK.Graphics.OpenGL;
#endif
I used the #if syntax similarly where there were small differences between the syntax of the routines.
It does not seem like OpenTK has its logic inside of a PCL in the first place, so your plans on putting it there are going to get hard to achieve.
However, if you split out your code, such that most of it is contained in classes, which are not highly dependent on the underlying platform, you will be able to create a Class Library Project for each platform and link your files between the platform specific projects. Inside of the classes it contains you will use #if definitions to choose whether to use AndroidGameView or GameWindow and the same goes for other platform specific types. It will make the code ugly, but this is the alternative to PCL.
You could try to see how much of the OpenTK code compiles inside of a PCL and inject the platform specific stuff at runtime, but it will require considerably more work from you. However, it will make the code a lot more cleaner to look at.
To ease the file linking, you could make one of those Shared Projects and chuck in all of the logic in there.
Some more info about code sharing here: http://developer.xamarin.com/guides/cross-platform/application_fundamentals/building_cross_platform_applications/sharing_code_options/
Dependency injection: https://en.wikipedia.org/wiki/Dependency_injection
Related
When creating a new app in Xamarin Forms I see these two options:
Configure your Forms App
Shared Code:
Use .NET Standard
Use Shared Library
Can someone explain the difference? I looked at the help and I am still confused. I'd appreciate if someone can give me any advice on this. Not sure if it helps but this app is self contained and no code in the app will need to be shared with any other application.
In terms of what you can achieve with both, it is the same. So, in the end, it's mostly a matter of taste.
The biggest difference is that a shared project is compiled into the app itself. It is nothing more than it says on the tin: it's a shared folder that you can use in all platform projects. Using platform-specific code is done through compiler directives.
With a .NET Standard project, you will get a physical binary. It is a project of its own. You can reuse it in other .NET Standard projects, although you already mentioned you won't be using it for that. Executing platform-specific code requires a bit different approach, using the DependencyService.
Seeing that they made a choice to replace the PCL with .NET Standard but keep the shared project points out that the shared project is here to stay for a while. I tend to like the .NET Standard library more. It feels cleaner and forces you to write cleaner code. Also, .NET Standard isn't going anywhere soon and if you decide that code should be reused down the road, you have the ability to.
A good overview, together with pros and cons can be found in the Microsoft Docs: https://learn.microsoft.com/en-us/xamarin/cross-platform/app-fundamentals/code-sharing
Just wanted to understand there are couple of code sharing strategies exist to achieve code reusable capability in Xamarin.
Which one should i use ?
Shared Project way OR Portable Class Library way ?
if you can explain with scenarios , it would be very helpful for me.
Thanks much.
Here is the Xamarin explanation.
The question is possibly duplicated but you ask specifically for scenarios.
If you ever wrote c cross platform projects, shared projects resemble the old-school way allowing you to use #if __IOS__ statements to run device platform code in your shared/common code files. A separate assembly is created for each target (say iOS or Android). They give advantages and disadvantages of each.
PCL generates one single assembly for the common code. PCL has some limited number .net features as shown here in this table. However, most of the important .net goodies are there as you can see.
Xamarin says that shared code method is easier but PCL is easier to compile a module and share or sell that with others.
When I make projects, I check what external plugins/components/ etc I want to use and make a decision based from. For example, you may want to use sqlite and there are different options for using shared and PCL projects.
What is the exact difference between xamarin shared project and portable class library?
When to use shared library and when to use portable class library?
Is this possible to write native functionality in shared projects like showing alert,accessing camera and use it for both android and iOS?
Can anyone please explain me.
In shared projects each code file will be compiled for each destination (Android, iOS, Windows Phone etc). You are able to include platform specific code by using #if compiler directives.
When you want to access the camera you need to write the access code inside an #if block for all destinated platforms. This can mess up your code but it can be easier to find the different implementations.
Learn more: http://developer.xamarin.com/guides/cross-platform/application_fundamentals/shared_projects/
Protable Class Libraries (PCL) are compiled against a general .NET subset which is compatible to all platforms you want. So you can access System.Net.Http but you cannot access any platform specific code. If you want to access the camera inside the PCL code then you need to access it by a generalized interface via dependency injection. There are some pretty good frameworks helping you to archieve this goal. One of the most famous is MVVMCross (https://github.com/MvvmCross/MvvmCross/wiki). Learn more about PCL: http://developer.xamarin.com/guides/cross-platform/application_fundamentals/building_cross_platform_applications/sharing_code_options/#Portable_Class_Libraries
I personally perefer PCLs because the code is much easier to read without any compiler directives. Using MVVMCross you are able to use plenty of plugins via NuGet. So you don't need to write your own classes for camera access, showing alerts etc.
I'm building some code with these portable class libraries at present.
I'm looking to target full .Net, WinRT Metro, Windows Phone, ... and then MonoTouch and MonoDroid. My experiments today show this can work - http://slodge.blogspot.co.uk/2012/04/experiments-with-portable-class.html
However, I have hit a fairly significant problem - MonoTouch and MonoDroid currently support these libraries in that you can consume PCLs as binary assemblies, but they don't allow linking between project files
e.g. I can reference MyLib.dll from a MonoDroid project, but I can't reference MyLib.csproj.
This is a problem as it means automated (resharper) refactoring doesn't work - and I seem to rely on this for most of my work!
I've seen that Microsoft publish targetting packs that allow you to extend class libraries, but I've not worked out where these install to or what they modify.
Here's the current Microsoft list: http://msdn.microsoft.com/en-us/hh487282.aspx
Does anyone have any knowledge about what these packs contain or how someone might make their own pack? If they're not too overly complex, then I would like to have a go at producing one for MonoTouch and/or MonoDroid.
This has come up a few times recently, so I wrote a blog post that should do what you want:
http://jpobst.blogspot.com/2012/04/mono-for-android-portable-libraries-in.html
Please let me know if have any issues!
I have an existing project created using C/C++ under a development environment.
Currently we want to facelift the existing form using a Window Forms application but the problem is the existing project is using Common Runtime Library = No /CLR and Runtime Library = /MTd.
But the a Windows Forms application is using Common Runtime Library = /CLR and Runtime Library = /MDd.
Please advise if it possible to use a Windows Forms application to create a form in the existing project?
Is there any tutorial regarding this?
The comment from MSDN was:-
Caution Do not mix static and
dynamic versions of the run-time
libraries. Having more than one copy
of the run-time libraries in a process
can cause problems, because static
data in one copy is not shared with
the other copy. The linker prevents
you from linking with both static and
dynamic versions within one .exe file,
but you can still end up with two (or
more) copies of the run-time
libraries. For example, a dynamic-link
library linked with the static
(non-DLL) versions of the run-time
libraries can cause problems when used
with an .exe file that was linked with
the dynamic (DLL) version of the
run-time libraries. (You should also
avoid mixing the debug and non-debug
versions of the libraries in one
process.)
http://msdn.microsoft.com/en-us/library/2kzt1wy3(VS.71).aspx..
The simple answer is no. A more accurate answer is kind of, but you probably wouldn't want to.
It is possible to use Windows Forms (i.e. managed code) for your user interface and something else (e.g. non .NET/unmanaged code) for your domain logic. However I'd guess that if you're asking this question then that is going to be a bit much for you to do at the moment.
I suggest that you create a user interface with Windows Forms and then have that user interface call a native C/C++ DLL. Google for PInvoke on how to call an unmanaged dll (C/C++) from managed (.NET) code.
If you did that then you would be much better positioned to answer this question.
My company software often has to have modules which mix managed and unmanaged code and user interfaces. What we do is to separate the modules into their own executables and expose the functionality as COM localserver objects. This way, the unmanaged code can have a user interface written in managed code.
However, you need to do alot of plumbing to get it to work. We do it this way because our applications have been deployed in the field for years and it will take years to give the entire program a makeover into .NET