Develop Reference

Building a Github library project locally in Android Studio 2

Like many a newbie I've been blindly clicking away in Android Studio 2 stumbling my way through building an app. Most of it just works so I've not really got my head into gradle.
Any road up, I've wanted to link into Strava and discovered that there were a couple of guys who had done the heavy lifting but on using a specific project, at the vital point of getting the data there is a coding problem. I thought the best approach would be to solve the problem and feedback.
So I downloaded the GitHub project in a zip and tried to do a standalone build and then things just didn't work. I think the basic problem is a) I don't know what I'm doing, and b) presumably the build on GitHub was done using different tools that are not set up for Android Studio.
So given that there is a working project on GitHub (specifically https://github.com/SweetzpotAS/StravaZpot-Android ) what are the dummy steps for getting that project to build locally in AS 2?
The problems I had are that on trying to open the project picking up the gradle file (couldn't find anything else to open in the root directory, the build didn't want to work - complaints about mixed projects. I stripped out the testing app and just tried to build the lib, but I didn't get a working lib in the output directory, just 2 25k stub aar files. Ideally I want to have that as a standalone project to build a local lib and then use that lib in my project (which I reckon is within my abilities!). Run out of Google search ideas!

How do I begin working on the Project Tango?

after a couple of weeks I have been unable to get the android set of tools to a functioning level with c++ before and have been given the opportunity of using a project tango, and though that sounds awesome and wondrous and would open a world of opportunity for working with VR... I feel like I am stuck at step -4. My understanding is limited, so bear with me.
I stumbled upon the PCL built for running algorithms on point cloud data, it was open source and appeared like a wonderful solution, it is written in C++ and I have a mild understanding of both c++ and java.
I have tried using Eclipse and the NDK and actually managed to get a project 'deployed' to the tango, however upon attempting to edit any file in the project, java or c++, it breaks and will never deploy again.
Now I am trying to use Android Studio, and after following about 5 conflicting tutorials on 'how to get C++/ndk working in android studio' I have yet to get a working environment.
So here is my question, and we can start at step one, any help is appreciated. How does one get c++ and the PCL working on a google project tango, is there a better way for someone of my skill level? The end result is a mapped 3d space with the project tango, with exportable data sets of manageable size. I have seen it done in demos on youtube, but thus far, like i said, I am stuck on step -4.

we are working on converting all project to android studio based, for now, here is the walk around to get you started:
Open Android Studio, import the project from the repo you just cloned.
Take the motion-tracking-jni-example as the example, copy tango-gl-render, tango-service-sdk, and third-party into the motion-tracking-jni-example/app/src.
Run ndk-build in the motion-tracking-jni-example/app/src/main folder.
ndk will generate the libs folder, rename it to jniLibs.
Go to Android Studio, in build.gradle(Module:app) file, add line 'sourceSets.main.jni.srcDirs = []' to the defaultConfig section.
Just click the run button in Android Studio.
What we did here is basically disabled the Android Stdio's JNI compile and manually built it using ndk.

Start with unity3d, its easy to get a working demo with a week with Unity3D.
And support is very good, documentation is top notch.
Hope this will help.

Tango NDK Tutorial Will help but the basic layout is
Setup a new project
Create your Java activity
Create a JNI file to bridge Java to the C++
Create your C++ logic
Setup your Makefiles and Gradle (probably the most annoying part)

Is it possible to debug C/C++ in Android Studio?

I'm writing an Android app that includes C/C++ code that is compiled alongside the Java code. My app is crashing during the execution of the native code.
Is there a way to step through Android C/C++ source and inspect variables as it is possible with Java source?
I am not necessarily looking for a way to step through the source from within Android Studio. That is obviously the ideal solution, however, if I need to use an external tool after starting the app from Studio, that's fine. I want to be able to step through the execution line-by-line and inspect variables.
Android Studio 1.0.2
Android NDK r10d
Edit: Stemming from the immediate response of, "Use Eclipse with ADT plugin", let me add more requirements.
This project started as an Eclipse ADT project. However, I have now migrated to Android Studio. My project is now built using Gradle, and my project directory structure reflects this. I am willing to use Eclipse; I am not willing to change my project structure in order to revert to Eclipse from Android Studio. If there is a way to open the Android Studio project in Eclipse and debug it that way, please elaborate on the process.

[UPDATE]
As of July 2015, Android Studio DOES support NDK.
You can learn more about it on this link.
[OLD]
NDK is not yet supported in Android Studio.
When we have to deal with NDK, the only solution is to use Eclipse.
EDIT
We basically keep Eclipse project with NDK feature (map in our case) and Gradle project with other (non-map) features. So everything that has to be done with NDK, we do in Eclipse and then include changes into Gradle project.
To be more precise, inside directory /src/main/ we created another directory called jniLibs and put the compiled *.so file inside architecture-specific folders (armeabi-v7a, armeabi, x86...). Then in the main class of Gradle project simply added a line
static {
System.loadLibrary("OurNDKLibName");
}
You can add this line only once per project. Maybe I am wrong but we did not have any issues for doing so.

As of version 1.3+ Preview Android Studio supports C++ debugging, quoting Android M Developer Preview & Tools:
Most notable is a much requested feature from our Android NDK & game developers: code editing and debugging for C/C++ code. Based on JetBrains Clion platform, the Android Studio NDK plugin provides features such as refactoring and code completion for C/C++ code alongside your Java code. Java and C/C++ code support is integrated into one development experience free of charge for Android app developers.

It isn't wasn't isn't working very well.
hello-jni fails failed with:
Starting LLDB server: run-as com.example.sample
/data/data/com.example.sample/lldb/bin/start_lldb_server.sh
/data/data/com.example.sample/lldb
/data/data/com.example.sample/lldb/tmp/platform.port1442695333842 "lldb
process:gdb-remote packets"
Error while launching debug server on device:
com.android.tools.ndk.run.DebuggerContext$StartServerException:
java.lang.IllegalStateException: Failed to read platform port
/data/data/com.example.sample/lldb/tmp/platform.port1442695333842
I'm using 1.4RC1
compileSdkVersion 23
buildToolsVersion "23.0.1"
And the "app-native" run configuration #Gerry mentioned. It's nearly there, but I can find no trace of an lldb directory in my app's private data folder. I do find a 400kb gdbserver in the lib directory linked from there, with my own *.so right besides. Unfortunately the option for debugging with gdb instead of lldb has gone with the upgrade from 1.3 to 1.4. NDK 10e ships a 400kb gdbserver binary in ndk\prebuilt\android-arm\gdbserver which it is (I guess). On September 15th the gdb debug howto https://github.com/mapbox/mapbox-gl-native/wiki/Android-debugging-with-remote-GDB was updated. This is harder than logcat debugging IMO, but a current topic, sorry to be so negative but I don't believe lldb actually works yet.
I have run hello-jni and reached the same conclusion.
So in answer to your question, it is not yet possible to debug C/C++ in Android Studio. Sorry this wasn't the answer you hoped for and I hope to be proved wrong with conclusive evidence to the contrary, but right here, right now, no chance!
UPDATE I raised an issue where I was given a fix for one phone.
UPDATE2 Too early to tell, it is experimental after all, but I am occasionally failing to connect, often if not always getting out of order stepping and breakpoints with nonsense parameter values. I just set a conditional breakpoint that didn't fire but the logcat shows it should. Initially I assumed it was my logical error, but it goes deeper.
Simply hitting breakpoints at all is very helpful but it is still a million miles short of Java debugging, or Vis Studio C++ debugging.
UPDATE3 Gone back to stable 1.3.1 as the canaray channel version was pausing for a toilet break every keystroke. While native debug build at least launches with my "fixed" phone, no breakpoints are hit even in hellojni, or a slightly extended version to give more opportunity. I'm used to logcat now but have had better degbugging experiences with Android, NDK and Eclipse. A more elaborate solution is also easier to break, but at least it works.

Yes, Android Studio does support C++ debugging at least with Android studio 1.5.1 and android-ndk-r10e.
In the old days, you will have to write make files Android.mk and Application.mk in order to build the C++ code in Android Studio. You don't need them any more. As long as you put them under the jni folder, gradle will be able to pick it up and compile it. You should see something like the following:
And also allow you to set break point and debug it.
You should follow this step-by-step tutorial and learn more about it. And read more about the documentation here. I've uploaded a complete working example so that you can download and try it out on GitHub.

With Android Studio 1.4 from tools.android.com, debugging is possible. When you open/create a project with C++[jni] code in it, Android studio would create a new configuration, something like $(module_name)-native
I would select this configuration, sync gradle, build, set breakpoint etc and run it with Android Studio. After a long wait, my debugger is connected, app is broken in[I think you could also set breakpoint at this time]; this break is not at my set break points, I let it go in android studio and my breakpoint is hit. Hope this helps
Some samples are supposed to work with android debugger

yes! it is possible to debug native code in android studio. As from the updates Android Studio 2.2+ support in built tools for debugging native code.

Google launcher building

I tried to build this project using JetBrains IntelliJ IDEA but it was unsuccessful (there were a lot of errors). The project has an Android.mk file, but I didn't see the C++ code.... How can I build this project? I've tried to use another IDE, then I tried building from the console but it was not useful. Perhaps, does Launcher3 need NDK to build it?

You'll need to isolate the launcher's code and then identify all of it's dependencies. If the code has any C++ code then it definitely requires the NDK and currently IntelliJ/Android Studio does not have any stable support for NDK based app development (though it is a work in progress) else if it is pure Java (most probably) then you'll have to manually add the classes and build the app from Android Studio! Either way you will have to dig deeper into the source and know for yourself. Unfortunately there seems to be no easier option, for now. I wouldn't mind being proved wrong for the matter.
EDIT :
I glanced through the code and I noticed there are no C++ source files or library (*.so) files. This isn't a gradle project and hence cannot be built as one. You'll need to setup a gradle based Android project and then begin adding the sources (src, tests etc.) and their dependencies (res etc.). You can start of here : Getting Started with Android development if you're new, else you can move to this : Gradle and Android

Android NDK with Visual Studio

I'd like to build some native libraries for android using the NDK (native development kit), but i'd like to use Visual Studio 2010 to do it. I've googled quite a bit but haven't found any information on it. Does anyone have any experience with this and know the steps necessary to make this happen? I have CYGWin installed, made sure i get Make (per the NDK instructions), but i'm not really sure of the next steps in terms of setting up the project, compiler in visual studio, etc.
If anyone knows of any write-ups, tutorials, or links to sample projects, that would be awesome, as there isn't much on google yet.
thanks!

Here's another solution, which integrates the NDK fully within Visual Studio. No makefiles. It behaves like a proper Win32 project:

Here's an excellent blog post about how you can configure your environment to debug android NDK code using Visual Studio.

Visual Studio is officially not supported.
Some problems (but not limited to):
MSVS cannot create the proper ARM binaries
Android makefiles (.mk) are not supported by MSVS
There are however, third party solutions:
vs-android
VisualGDB
You might want to check out DS-5 as well, though it's not Visual Studio.

The answer depends on what kind of integration you require.
To just build the native Android code from Visual Studio you can create a new Makefile project, and make it run ndk-build.cmd when you press "build". If you would like to get the error messages mapped as well, you will need to parse the output of ndk-build.cmd and convert it to a format that Visual Studio can udnerstand.
If you want to debug your native Android code from Visual Studio, you will need a third party tool that will control ndk-gdb on behalf of Visual Studio and provide workarounds for several bugs (e.g. rebind breakpoints when libraries are loaded).
You can try our VisualGDB for Android tool that does exactly that - creates projects that wrap ndk-build and controls NDK debugger on behalf of Visual Studio. If you need more information, there is a step-by-step tutorial available.

I have not found a direct clean solution, here is my workaround.
I develop my native code on VS as a static library, and use some test project to try it as a console aplication.
When it is ok, from cygwin I use a little bash script that copies all needed files to the jni folder and launch the standard android ndk make command. (also copy some file to assets folder when needed), producing the executable in the right folder.
To use the pthreads I have linked my projects to pthreads-win32.
The only files I do not compile in VS are the jni code.
I hope this can help you.

There's also a couple of other third party alternatives for developing ANdroid apps with VS in addition to those above. There is the open source dot42 located at http://www.dot42.com and Remobjects, http://www.remobjects.com , which allows you to program in c#, Pascal, and Swift. I have played with the trial of Remobjects and am now starting to play around with dot42.
My use of the remobjects trial allowed me to recreate in c# the first five chapter projects in the textbook of the Android course I took. I haven't had the same success with dot42 so far but I need to find some time to really give it a chance.