Develop Reference

Libgit2sharp Xamarin Android integration

In order to make some proof of concept prototypes, I'm planning to add git functionality to my Xamarin Android app.
For doing so, I was taking a look at the libgit2sharp library, especially the latest prereleases that seem to be released with .netstandard 2.0.
The NuGet package installation works perfectly, but obviously, it fails when I try to make any call to the library because the missing library files that are not built in the libgit2sharp.nativebinaries project.
Is there any way I can build on my own these libraries?
If not, can you think about any other alternative?
Kind regards and thanks in advance

How to use FPC to compile Free Pascal code to *.apk files?

There is an app out there called "PascalGUI" (Link to google play store) which can compile the code into APK files.
I looked through the web and emailed the developer but i cant find any way how i could do the same thing. I think he uses the official fpc sources and just passes the code but im not sure.
Is there any documentary or someone who knows how this could have been made?

Generally, FPC is cross platform, so it can target many processor architectures. Creating Android Application using FPC can be done through Android NDK, and it can also be done using Android SDK.
Michael Van Canneyt wrote in his page about creating Android using FPC and Android SDK.
I'm not sure if that App uses same approach, but this seems to be very similar.
Update (12/2017):
The easy recommend way to build Android applications (APK) using Lazarus -as for now- can be done using Laz4Android and "Lazarus Android Module Wizard".
Hope this help.

How to use Android Studio with Cocos2d-x

I work as an android programmer for just under a year now, and I just started to learn about android game development. The framework I choose to work with is Cocos2d-x.
I have seen guides and tutorials on how to use Cocos2d-x with eclipse, but I'd really like to know if it's possible to be used with Android Studio.
From what I've read, it is now possible to build NDK projects with gradle in Android Studio, which is good news. Nevertheless, I have yet to find any information about C++ programming using Android Studio. Eclipse uses the CDC ( https://www.eclipse.org/cdt/ ) plugin to achieve this.
Is there anything similar to be used with Android Studio? I have found some C/C++ enabling plugins for the IntelliJ Platform, but they were no longer updated.
Has anyone else tried this before? Did it work? Can you provide a step-by-step guide, for a newbie like me, who's dealing with this kind of problems for the first time?
Thank you for you time,
haxm

Android Studio currently isn't well set-up for native programming. While the build system supports the NDK, there's no editor support for C++ files (it's not as if it won't work, but the IDE won't give you any editing assistance), and neither is there any debugging support. JetBrains has announced that they're working on new C++ support for IntelliJ, and this is something we're looking at for Android Studio, but it's not on the roadmap yet.

Recent version of cocos2dx v3 (from github for example)
have proj.android-studio project
At this moment I have no success to build it but maybe in future it will be fixed

I just went through the setup for this example code. The project compiles and has a ton of sample code. Scott Barta's answer still stands as an important caveat, but wanted to share the link in case it was useful.
I also found this useful for some NDK background/how-to.

How to add WebRTC functionality in android app

How can I easily add WebRTC functionality to my android app so that I would be able to play video stream in MediaPlayer?
What library (.jar file) do I have to add to referencies?
Could you add some code example please?

Actually, there is no such ".jar" files for you to reference right now.
WebRTC is designed for web browsers, even if it can be build for android and iOS.
for your question, I think you may need to learn how to build WebRTC on Android or iOS.
for Android, you should know NDK and JNI first. then build whole webrtc projects or standalone VoE\ViE even NS\AECM\VAD\AGC modules for android.
for iOS, you should also build it by yourself, but you may need this help.
all of these info can be found on the internet, especially google group.

checkout following link : http://www.webrtc.org/reference/getting-started
I have added my project on github: https://github.com/SDkie/Webrtc-for-Android, you can fork and make changes in it.

Please take a look at http://www.webrtc.org/native-code/android.
It has all the information on how to build webRTC for android.
The java wrapper for the native webRTC libraries:
https://code.google.com/p/webrtc/source/browse/trunk/talk/app/webrtc/java/#java%2Fsrc%2Forg%2Fwebrtc
It has the instructions on how to build the native libraries.
It also has an example app that uses webRTC to talk to the https://apprtc.appspot.com.
https://code.google.com/p/webrtc/source/browse/trunk/webrtc/examples/android/media_demo/README
I could not find instructions on how to create an Android Studio Project and build it with gradle though. If anyone finds it, please share.
I hope it helps

One option is to use the crosswalk, you can create a native app using the crosswalk as a webview in your project.
In my case the Web-RTC worked without any problems.
Here are some tutorials on how to add the crosswalk on your project.
https://diego.org/2015/01/07/embedding-crosswalk-in-android-studio/
https://crosswalk-project.org/documentation/embedding_crosswalk.html
I hope this helps.

Scala Programming for Android

I have followed the tutorial at Scala and Android with Scala 2.7.3 final. The resulting Android App works but even the most basic application takes several minutes (!) to compile and needs 900 kb compressed, which is a show stopper for mobile applications. Additionally, the IDE runs out of memory every now and then. I assume dex is not made for big libraries like the scala-library.
So my question is: Has anyone actually done this and is there any cure for this?

I've written some basic Android applications in Scala, nothing too epic. Not being a Java programmer I was suggested to use a "treeshake", I was explained by a friend that this strips out all the unnecessary libraries from the jar files.
I have not documented it, but I found that someone else already has:
http://chneukirchen.org/blog/archive/2009/04/programming-for-android-with-scala.html
Proguard is not the only solution, you might find something that suits your work flow or is more suited for your environment.
Additionally google have just realised JACK , which deals with quite a lot of reducing build and memory times see https://source.android.com/source/jack.html

You can now use the Android plugin for Gradle to create Android applications in Scala. It incorporates the ProGuard tool to trim the fat from the resulting APK file, so seems to meet your needs.
https://github.com/jvoegele/gradle-android-plugin/wiki

There is also an plugin for the Scala-based builder sbt: sbt-android-plugin.

For tutorials and examples, see also Stéphane Micheloud's "Exploring Android" page: http://lamp.epfl.ch/~michelou/android/

I verified this detailed solution with Eclipse 3.7, Scala 2.10 and the plug-in AndroidProguardScala v50:
https://stackoverflow.com/a/11084146/1287856
Everything works fine. A simple test application with scalafied main activity class only takes 38Kb. Libraries projects are supported. Proguard is activated when exporting the project.

Developing Android apps for Scala is continuously evolving. The current best way to do it appears to SBT in conjunction with the android-sdk-plugin, which is maintained* and works well for me in my Scala/Android project. A somewhat recent example that demonstrates the use of this plugin with the already mentioned Scaloid can also be found.
Please note that this question is a typical example of a question with outdated answers on Stack Overflow. This answer will likely become outdated at some point as well.
* The other SBT based projects mentioned in this answer thread don't appear to have code being written for them in the last six months at the time of writing. They may have compatibility issues with newer versions of Scala and SBT.

If you use maven, use android-scala-test as a startup template. It works great for me out-of-the-box.
Scaloid is an Android API wrapper written in Scala that help you to write your Android program in Scala-style.

You can use the Scala on Android without SBT, it built externally by Gradle to create Android applications.
https://github.com/yareally/android-scala-intellij-no-sbt-plugin
Gradle is more native building tool for android than SBT.
There is good example of Scala client and server side solution concept, and gradle building tool as advance for IntelliJ IDEA workbench.
Big advance that core classes are common for client and server.
https://github.com/ghik/akkdroid
Good tutorial for IDEA and android-plugin:
http://fxthomas.github.io/android-plugin/

The biggest issue with Scala on Android is the compile times.
Possibly because of the Proguard class stripping compiles with IDEA13/Scala plugin on a Dual Quad Core (8-CPU) E5450 Xeon with 8GB can take two minutes or more.
I simply moved back to Java after completing a largish Scala Android project as compile times were too frustrating.