I'm fairly new to Kotlin and I noticed that the API docs tend to have differing support for the major Kotlin platform targets JVM, JS, and Native (I'm asssuming Common means it should be supported the same everywhere). My use case for Kotlin is Android development, but so far I haven't found a definitive answer as to what platform target compatibility building for Android implies. Presumably it would be JVM since kotlinc does compile Java bytecode as the first step in and Android build, but that's confusing and unintuitive since Android has nothing to do with the JVM itself. In the Kotlin FAQs describing what Kotlin is, they mention Android as a target platform; however, Android is not listed in the Platforms heading of their documentation (only JVM, JS, Native, and Scripting).
Is Kotlin targeting the JVM with respect to its API when programming for Android? If not, what platform(s) is/are applicable when browsing the Kotlin docs for the purposes of Android development?
Yes, on Android Kotlin compiles into and is run on the JVM. That's why it interacts with existing Java code/libraries and the Android framework (which is written in Java)
Related
I'm not an android developer nor a java expert but I've been searching a lot for developing android apps using Scala lately. I found some things like Scala on Android and also a lot of questions and answers here as well but most of them are outdated (they're mostly between 2013 to 2017). Also, Scala on Android's last release was in 2017. So, I guess there wasn't a really big improvement there.
I read somewhere that the main issue is lambda expressions in java but that make no sense. What is the real reason that holds developers from using Scala in android?
I know that Kotlin is the preferred way to develop android but is there any way to develop the whole app in Scala? Is it even possible? if it is, is it a good idea?
What about Scala 3? Is there any hope that the new version of Scala have a future for android development?
The broad reason is that the maintainers of the official Scala compiler made a decision to only emit bytecode targeting Java virtual machine versions for which Google did not (at the time) support compiling into Dalvik. (The Oracle v. Google legal proceedings may have influenced Google's decision).
In the interim, Google has added support for some Java 8 features. However, the support is not complete, and Scala uses some features which Google's tooling doesn't support.
This scala-lang.org discussion covers some of the major hoops which had to be jumped through to build an Android app in 2.13; it included patching the Scala standard library in order to make the collections work. It does look like there's a chance Scala 2.13.7 will be patched to address at least some of the issues.
In the meantime, the historical Scala on Android project had largely been abandoned; there is apparently the beginnings of an effort to begin a new project based on Scala 2.13 and Scala 3.
Currently, we are developing a .NET Standard class library that will be used by different Xamarin.* platforms.
I was wondering if there is a way to use the shared code in a native Android project (maybe produce an AAR/JAR file).
The reason I need this functionality is because our company provides an AAR to one of our customers (that is used by a native Android project), and we would like to keep a single source base instead of two.
Thanks in advance!
Update:
The name changed to ".NET Embedding" and it is at v0.4 at the time of this update.
https://developer.xamarin.com/releases/dotnetembedding/dotnetembedding_0/dotnetembedding_0.4/
New instructions:
Installing .NET Embedding
Original post:
You can use Mono's Embeddinator-4000
It supports various language consumers, so it surfaces .NET code as idiomatic code in the target language. This is the list of supported languages at present:
Objective-C: mapping .NET to idiomatic Objective-C APIs.
Java: mapping .NET to idiomatic Java APIs.
C: mapping .NET to an object-oriented like C APIs.
Embeddinator-4000 is a tool that allows your existing .NET Code (C#, F# and others) to be consumed from other programming languages and in various different environments.
Java is currently in a preview state for macOS, Windows, and Android.
The platform is selected by passing the --platform= command-line argument to the embeddinator. Currently macOS, Windows, and Android are supported.
re: https://mono.github.io/Embeddinator-4000/
As a part of the requires For Android you will need Xamarin.Android 7.4.99+ and Android Studio 3+ (Java 1.8) but if you are building Android apps with Xamarin and Java you would have those already.
Note: This tool is in Preview, so review the open issues and post new if needed.
re: https://github.com/mono/Embeddinator-4000/issues
Note: This is not trans-compiling, but embedding Mono's runtime in a native package that allow CIL code, AOT'd (i.e. iOS) or not to run within a different language/runtime.
Currently, we are developing a .NET Standard class library that will be used by different Xamarin.* platforms.
I was wondering if there is a way to use the shared code in a native Android project (maybe produce an AAR/JAR file).
The reason I need this functionality is because our company provides an AAR to one of our customers (that is used by a native Android project), and we would like to keep a single source base instead of two.
Thanks in advance!
Update:
The name changed to ".NET Embedding" and it is at v0.4 at the time of this update.
https://developer.xamarin.com/releases/dotnetembedding/dotnetembedding_0/dotnetembedding_0.4/
New instructions:
Installing .NET Embedding
Original post:
You can use Mono's Embeddinator-4000
It supports various language consumers, so it surfaces .NET code as idiomatic code in the target language. This is the list of supported languages at present:
Objective-C: mapping .NET to idiomatic Objective-C APIs.
Java: mapping .NET to idiomatic Java APIs.
C: mapping .NET to an object-oriented like C APIs.
Embeddinator-4000 is a tool that allows your existing .NET Code (C#, F# and others) to be consumed from other programming languages and in various different environments.
Java is currently in a preview state for macOS, Windows, and Android.
The platform is selected by passing the --platform= command-line argument to the embeddinator. Currently macOS, Windows, and Android are supported.
re: https://mono.github.io/Embeddinator-4000/
As a part of the requires For Android you will need Xamarin.Android 7.4.99+ and Android Studio 3+ (Java 1.8) but if you are building Android apps with Xamarin and Java you would have those already.
Note: This tool is in Preview, so review the open issues and post new if needed.
re: https://github.com/mono/Embeddinator-4000/issues
Note: This is not trans-compiling, but embedding Mono's runtime in a native package that allow CIL code, AOT'd (i.e. iOS) or not to run within a different language/runtime.
Since 2 Years I am working as Android Application Developer. I generally use android SDK for all the Android Apps Development. Now I have a project which is an Android App in which I have to use SDK as well as NDK for App development (As per Client requirement).
But as I don't have any experience with NDK I don't know what is it. In some Blogs I have read that NDK development is based on c++.
Is it true that to work with NDK one must have the complete knowledge of c++ ?
Please Help !!
Use of NDK means you have to write portion of code in C/C++ just to achieve the speed. If it is client requirement then you have no option. But keep in mind that you should use NDK only when you feel you need better performance. And of course you must have some understanding of c/c++ to use NDK.
NDK
NDK is a set of tools to compile C code to shared lib,
which you could use in your app - and that's all.
Enables legacy code re-use between iOS and Android platforms
Good for implementing CPU intensive operations that don't
allocate much memory like signal processing, physics simulations.
SDK
SDK is the main development kit for Android apps - it contains tools for Java and resources (png, xml) compiling, packaging to apk file, installing, running and debugging them on a device, an emulator, documentation, etc.
Java has superior memory management model Superior threading model Better exception handling model Rich set of libraries Superior support for unicode characters.
I have been asked to research on how to make an android app using Delphi, Now I am not sure that this can be done. I have not come across tutorials on the same. Somebody please clarify on this issue.
Delphi cannot create Android apps at present. This is being worked on for a future release.
Update: As of the release of XE5, Delphi now supports Android development for certain ARM hardware using the mobile Delphi compiler.
Free Pascal is now able to produce code for the Java platform - so it might be feasible to create Delphi code which can be compiled to Java bytecode with FPC and then converted for the Dalvik VM.
The FPC backend for the Java Virtual Machine (JVM) generates Java byte
code that conforms to the specifications of the JDK 1.5 (and later).
While not all FPC language features work when targeting the JVM, most
do (or will in the future) and we have done our best to introduce as
few differences as possible.
This FPC JVM backend is not related to Project Cooper by RemObjects,
nor does FPC now support the Oxygene language.
Two choices to follow at present - check out Delphi for Android which is in design/beta phase: http://lenniedevilliers.blogspot.com/
Or, use Prism http://www.embarcadero.com/products/prism (and check out their Oxygen for Java coming soon http://www.remobjects.com/oxygene/java.aspx which is in Beta)
With DWS as backend script compiler and the soon to come Smart Mobile Studio (aka OP4JS) component library and RAD interface it will be possible to make apps running with HTML5 in android applications (and iOS or any other html5 compatible system).
By using object pascal, all Delphi and freepascal users will have a short learning curve and a high code reuse factor.
There are some samples using only the DWS backend here :
taming-the-flock-with-object-pascal
taming-html5-verlets-with-object-pascal
Update :
More samples can now be found on their homepage.
First steps with native Android applications made with Lazarus/FPC are here.
One way is to use a combination of Delphi, Sencha and PhoneGap by leveraging the Raudus framework. You can try the RaudusEmployee.apk example on your phone and see if this method will work for you.
http://www.raudus.com/samples/
This is not a native application, but similar to many new HTML5 applications.
Delphi XE5 is now released with Android support.
http://www.embarcadero.com/products/rad-studio/create-android-apps