Develop a native source code for Android and BlackBerry - android

Is there a way to develop classes for Android and BlackBerry ? In this I mean that BlackBerry and Android have different collections.
So I would like to know what is the best way to develop such files (reflection, different files, ...)

Your best bet is to write to a common interface, so that your higher-level code can be consistent, and the parts that will be different, will be abstracted into their own libraries. This way you can write applications that use a common codebase, though most of the work will take place in your libraries, as that is where you connect to the platform.
This way you can try to minimize redundant work, but take advantage of each platform more completely.
If you limit yourself to what each can do then you are shortchanging your users as there are a great deal you will not be able to do, or do well.

We have common code for Android and BlackBerry. You know that BlackBerry is J2ME based so its Java 1.3 compatible, and Android is Java 1.6 I think. This places significant limitations. I will list what I remember below.
All common modules you code has to be Java
1.3 compatible if you want it to work on both platforms. This means
no collections framework, no
reflection, primitive string
handling/localization with strings
in class files etc.
It will be very hard to have ALL code that is works on both platforms. So it is better to have some common packages, then BlackBerry and Android packages that work on those platforms.
Nightly build system is really helpful as it will catch errors that break one platform build, caused by changes for the other platform.

Related

Are there cross-compilable OpenGL examples made with Oxygene?

We have a working OpenGL project made for PC (works on MacOS and Linux under Wine as well) which we want to try to cross-compile to tablets. Delphi XE2/XE4 offers iOS support, but there's no Android yet and judging from iOS implementation history it might take 1-2 years. Now we start looking into other possibilities which will allow us to keep the majority of Pascal codebase (80k lines). So here's the question for the Oxygene:
Are there any examples of OpenGL applications made with Oxygene that can be cross-compiled to work on PC/MacOS/iOS/Android ?
If not, what alternatives are there (except Lazarus)?
AFAIK there is none.
Even the low-level Sugar cross-platform RTL is not finished. It would be a first mandatory step to be done before accessing higher level libraries in a cross-platform way (i.e. with identical source code), like OpenGL.
So with Oxygene, you have a great cross-compiler, but you are tied to use the RTL available on each platform.
You can compare with two object-pascal compilers:
With FreePascal, which has built-in OpenGL units, and already several libraries over it - one of the most powerful/known is GLScene;
With SmartMobileStudio, which has built-in WebGL support and can do amazing things on modern browsers - WebGL is a translation of the OpenGL API/concepts in HTML5.
Oxygene doesn't attempt to be source compatible with Delphi. What's more the runtime libraries used by the various Oxygene flavours differ entirely from those used by Delphi. So you won't find any serious libraries that have single source that can compile on Oxygene and Delphi.
The way that RemObjects have developed Oxygene on different platforms is quite interesting and radically different from the approach taken by Embarcadero with Delphi.
With Delphi the goal is that you can single source development for all the platforms. That is made possible by the FireMonkey framework which presents a common interface to all platforms. Obviously you need to vary some elements of an app to account for device differences.
With Oxygene, each platform is targetted separately. So for Windows, the runtime is .net. For Java it is the JVM and for Apple platforms you target Cocoa.
All this means that you cannot expect to write a GUI app in Oxygene and have it work on multiple platforms.
So not only can you single source your app between Delphi and Oxygene, you cannot readily single source multiple Oxygene targets.
Now, you can probably port to Oxygene or FPC without too much trouble. But maintaining single source is liable to mean a lot more effort. Whether that's worth the effort is debateable. In the long run you'll want a codebase in one of Delphi, FPC, Oxygene, or even something radically different. But you won't want your code spread out over multiple languages.
You can write or own OpenGL layer in Oxygene with the usage of mapped types like it is used in the sugar open source project.
It sounds pretty cool. In your code you have just to use one class which is during compiling direktly mapped to the underlying platform class method, without an overhead of that layer.
IMHO, when Oxygene is growing, we will then find a lot of such "suger" layers and write once compile anywhere will come closer :)
Edit:
Using OpenGL with .Net
OpenGL Java Tuturial

how to use mono in my cross platform project

I've been searching solutions for my enterprise apps, at least 3 platforms need to be supported, which are iOS, Android and Window Phone. After a whole day's search, I finally set my eyes on 2 promising cross platform solutions, one is monocross and the other phonegap.
monocross seems to use c# and .net at all, is it possible to access native libraries and languages? I read somewhere it's compiled directly into binaries that can execute on target platforms.
And about phonegap, it uses webviews on each platform to provide the capabilities of presenting user interfaces to final users. As it's implemented via interpreted language and high level apis, the performance may not meet our needs.
Finally, we(my team) decide to give it a try with mono, the architecture is illustrated as bellow:
+++++++++++++++++++++representation layer++++++++++++++++++++++++++
[monotouch,monodroid,silverlight]or [native gui calls] or [html5/js/css]
+++++++++++++representation controller/business logic layer+++++++++++++++
[ mono/c# ]
++++++++++++++++++++++++++++server side+++++++++++++++++++++++++++
[ the cloud ]
I want to use mono/c# to write some common purpose business logic and data structures, and when it comes to some common platform features, like storage service, notifications, I'd like to wrap them up on each platform and expose uniform apis for c#(business logic layer) to use. As to the representation layer, we decide to choose from the 3 optional solutions listed above.
To make this happening, first I have to figure out if it is possible to call native frameworks.
So, my questions are:
1, How does mono work, I mean, are the c# codes compiled into binaries that can be executed directly on iOS, Android and Windows Phone?
2, Is there a mechanism to make native invocations? Like in cocos2d-x, I can call java methods via JNI, and in iOS, c++ can call oc directly. Can I call cocoa touch stuffs in mono with c#?
3, Is it possible to manage all these stuffs in one single project, and how to build them?
4, Are there any better solutions?
Any suggestions will be appreciated, thanks for your patience!
I wonder why Xamarin does not land on the first page of your search result,
http://xamarin.com/features
But that's what the Mono guys created for the C# developers that want to target mobile platforms. MonoTouch and Mono for Android are there each featuring a common library base with Microsoft .NET, and also platform specific bindings.
Your non-UI code should be able to be used in portable libraries and share among them. Microsoft's portable library is Windows specific, and right now I am not sure how much Mono guys can embrace that, but even if PCL fails, you can create multiple platform specific projects based on the same copy of source files (which I did in #SNMP). The remaining task is to develop platform specific UI for Windows Phone, iOS, and Android.
There are tons of articles showing the features,
http://docs.xamarin.com/
and also many successful apps
http://xamarin.com/apps
The best way to learn a product is to try it out (for free in Xamarin's case). This also applies to MonoCross (which is a framework built upon Mono).
I am not familiar with PhoneGap, so you need someone's advice on that.
Disclaimer: this is not a complete answer - but I do hope it answers at least part of your question
I encountered a similar problem when I started cross-platform dev using the Mono products 18 months ago.
The approach I've built since is called MvvmCross - it forked off of MonoCross a long time ago - now shares no code with it (but maybe we'll team up again one day!).
The approach uses PCLs to share code. This is not entirely painless, but is easy after you've done a few setup steps - http://slodge.blogspot.co.uk/2012/12/cross-platform-winrt-monodroid.html
You can learn more about this approach on this video: http://slodge.blogspot.co.uk/2012/12/mvvmcross-video-presentation-xaminar.html

MonoTouch / MonoDroid Service Layer incompatibilities?

We've begun to build Cross platform Android/iOS apps, having built exclusively in MonoTouch before. We're evaluating MonoDroid.
Our apps need to consume JSON and we'd like to use ServiceStack. Xamarin has a ServiceStack branch which we're using - https://github.com/xamarin/ServiceStack
We'd like to have a common project responsible for GETting and POSTing JSON. ServiceStack by Xamarin has different DLLs for Android and iOS. How do we have a single project and use ServiceStack to get at our JSON?
We're open to other options to get at JSON in a unified way?
By and large, managed *.dll's compiled for MonoTouch that don't have a dependency on MonoTouch specific types are compatible with Mono for Android projects.
ServiceStack is a great example of this. I've personally used it for multiple projects across the Xamarin mobile framework offerings.
As a general rule I tend to encapsulate all invocation to my web services using a partial class with async methods, like FooProjectRestClient. And then if there ever is any sort of segmentation that needs to occur it can happen in a shared class using #if defs.
The reason why there are MonoTouch and Mono for Android specific libraries is often because of the (smaller, Silverlight-like) profile available (e.g. things that depends on new FX4.0 features needs to be cut out). They are often the same code re-compiled with SILVERLIGHT (or MONOTOUCH, MONODROID) defined.
The reason for MonoTouch only specific librairies are generally because its environment (iOS devices) do not allow JIT'ing. So there's no code generation (e.g. System.Reflection.Emit) or dynamically (down)loading code... However it's often possible to provide (less performant) workarounds or skip a few features and keep a special version of the library for MonoTouch.
Now back to having a single shared assembly/project. The special MonoTouch assembly (generally the same code re-compiled with MONOTOUCH defined) is still a valid .NET assembly and often can be used in Mono for Android, Mono or .NET (once recompiled, even with MONOTOUCH). It's definitively not optimal but it's something you can try.
Another one is having the same projects (e.g. MyLib), across several solutions (e.g. MonoTouchApp, M4AndroidApp) and use special configurations (just like there's an iPhone|Debug one) to set different defines (e.g. MONOTOUCH on iPhone*|*). That can allow you to keep the best feature implementation in each platforms (e.g. in case the same feature is implemented differently).
I would try the later first (config), then sharing the MonoTouch special assembly and finally (if it really does not work) look for other alternatives.

Creating Android apps without Java

I'd like to start creating Android apps but I don't like Java. I read that scala can be used to do it. Are there another option?(Clojure?)
I'm a Python/Django developer so it would be great to learn a pretty different language.
At this point Scala is the one that is most mature..I wanted to try groovy myself but its not even out of alpha..
Plus Scala on android has docs..:)
It's not hard to do with Mirah (formerly Duby), a very young language based on Ruby that compiles to bytecode that's basically indistinguishable from Java's, but adds some great new features like closures, type inference, and obviously a Ruby-like syntax. It's particularly well-suited for Android because it has no runtime or standard library (it uses compiler plugins instead) outside the JDK, whereas basically all other JVM languages bring along a lot of baggage, especially languages that weren't designed to target the JVM (like Ruby and Python).
http://github.com/technomancy/Garrett
Much nicer than writing Java!
for clojure development a useful tutorial: http://riddell.us/ClojureAndAndroidWithEmacsOnUbuntu.html
Clojure gets a LOT of benefit from android-2.2's JIT compiler and has not really been widely adopted on previous versions.
Appcelerator Titanium is an awesome environment for using web-ish skills (like HTML, CSS, and JavaScript) to build native apps for Android (and iPhone, and desktops, etc.). For example, the gang at Intridea have made several popular Android & iPhone apps with Titanium Mobile, including the OilReporter app that has been used for gathering data on the extent of the Gulf oil spill.
If you use Python, maybe SL4A (Scripting Layer for Android) is a good choice.
You could write python script that runs on Android and use Android API, but it also has a drawback that you need install Python/SL4A runtime library on your Android device.
In addition to the other solutions listed here previously, you have:
PhoneGap
Rhodes
AIR (pre-release)
AppInventor
Clojure
Another immature implementation is JRuby/Ruboto: http://blog.danieljackoway.com/first-ruboto-release.html

Is Scala for me? (C# developer with focus on functional / OOP style)

I want to learn a new programming language and develop for the Android platform.
I'm a fulltime C# / F# - developer and I also use C# in the most functional way possible (because I like this paradigm far better than the old skool style "lets iterate and describe to the barkeeper how to make the cocktail", to quote Microsoft).
However, I have a strong dislike for Java, because in my opinion it is outdated and, hm, a dinosaur - it lacks exactly the features I like best about C# and F#.
On the other hand, developing for the Android platform requires JDK use.
So, would you recommend Scala? Or is the JDK stuff not for me at all?
Scala rocks exactly as you'd expect that a functional language built on the JVM might. The only downside compared to C# for me (I haven't used F#) is that the IDEs haven't quite got the refactoring down yet. It isn't bad. I'm using IntelliJ's plugin for Scala; that seems to work well enough.
Of course, the main benefit you get from Scala is being able to leverage all the many Java libraries out there, since they work (mostly) interchangeably. That might not be important for the Android platform where your apps will be small and stand-alone, but for commercial development it means that Scala is already a serious Enterprise language. Learning Scala will therefore give you more job opportunities in the future. I would definitely recommend Scala.
One of my large financial clients is using it as their server-side language and it works beautifully. There are a few interesting clashes between eg: Scala and Java lists, Scala and Java booleans, all well-documented, but otherwise it's smooth.
Good luck!
An alternative to using Scala might be the upcoming MonoDroid, a port of the Mono runtime to android. Unfortunately it isn't completed yet, and will cost something like 400$.
I'd recommend looking into scala if you develop a new application for android and only use monodroid if you want to create a port of an existing .net application.

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