I asked a rather difficult question for me about compiling the toxcore library for Android. I read the instructions on the official git page, but without success.
I tried to build on a virtual machine under the lubuntu shell, but unfortunately I got only the toxcore library (you also need toxencryptsave). And the library itself was not read by Qt.
Tried to build via cygwin. The results are the same, but now the .so libraries are not built in addition.
Questions:
Does the readability of the library depend on the compiler? (For example, I built it on a virtual machine under CMake, and in Qt under android under CLang)
Who did it? Can you share more detailed instructions for collecting libraries for CLang
Thank you all in advance. If you really help, I will kiss everyone on the forehead
Related
I'm trying to install some python packages (pillow) for QPython on Remix however I get the error that arm-linux-androideabi-gcc does not exist.
I googled and I think I need NDK, however looking at the website (https://developer.android.com/ndk/downloads/index.html) I couldn't find a way to do this on android.
Any help is much appreciated, thank you!
Installing the NDK on Android? As in running the NDK compilers on an Android device? We don't support Android as a host OS for the NDK.
Check out AIDE android ide from the Google playstore
Despite Dan's answer, which I respect. It's not entirely accurate. The Android ndk build system doesn't allow for for host to be set to the $TARGET_ARCH, but building it manually in much the same way you would for any custom toolchain is entirely possible.
I should note that I have only done this for gcc, and have not attempted to do so with clang.
From Googles ndk toolchain repo just take the essentials needed, gcc, binutils, gmp, mpfr, etc and set your host and target to the ndk toolchain gcc. Use the ndk sysroot as build-sysroot, and then just add your compiler flags and with a little fiddling you should get it.
Id be happy to post more, it's been a project of mine to build Android on Android, also i highly recommend adding static versions of the ndk libs, as the android system doesn't have a c++ lib, and a few others. You may have to build some manually using aosp build system
I built it with stage-one flags so that the binaries would be static, as you never know when android might remove a lib that your toolchain depends on.
I encourage you to try, as an added benefit you will then he able to build many useful android native binaries that usually aren't available without editing the aosp source. Also having the ability to build binaries on the fly is very useful
What is the best way to profile plain C/C++ android executables on a rooted android device?
android-ndk-profiler seems to support only ndk libraries linked to Java.
Any suggestions?
Thanks
I was faced with the same question recently. After looking into several alternatives I decided the best option (the one I made to work, at any rate) was to build Valgrind for Android.
This page describes how to build Valgrind for Android. See also my GitHub project for a slightly different build procedure, usage notes and prebuilt Android ARMv7 binaries.
Android NDK profiler work by GCC compiler trick so should work independent
of JNI
This link has the details
http://code.google.com/p/android-ndk-profiler/wiki/HowItWorks
As long as you can insert the startup and cleanup code into your C/C++ code it should work
You can find all the information you will need here
http://code.google.com/p/android-ndk-profiler/
I am building C libraries that will be used by an android app(through either JNI or the NDK, I've never used the NDK though) and I am wondering what IDE/development environment is best to use? I've basically only used Visual Studio for native development and I'm not sure how to adapt to building .so libraries for use on android.
Thanks
EDIT: Update -- I want to avoid makefiles if possible (never used them) and rather use a complete IDE such as the case with visual stuido to compile
Generally, cygwin (i.e. command line) is used for building Android native code. But you can also try to use Eclipse for this purpose. It doesn't help very much but it highlights syntax and you don't have to switch to other apps to write code and build your app. You can read more about using Eclipse for C/C++ Android development here.
I would strongly recommend that you use the NDK's compiler.
Normally this is done by writing an Android.mk in accordance with the instructions for the NDK. It is not complicated. The easiest thing to do is to grab the hello-jni sample app and just make the necessary changes, for example substituting your source files into its android.mk.
You can stay in visual studio if you like that as an editing environment, simply using the ability to bind an external command to a keystroke to launch the ndk build script. Ages ago I had figured out how to reformat GCC error messages with sed into something that VS could parse to make them click-able, though I soon moved development of that project under linux.
I think a lot of people use Eclipse as their IDE for Android development. I use it and its pretty good. You shouldn't have any problems if you're used to VS.
The Android SDK comes with a plugin, the Android Development Tools (ADT), to develop applications for Android inside the Eclipse IDE, which is same kind of beast as Visual Studio. And within that IDE, it is possible to use JavaCPP (disclaimer: I am the author) to have it compile all the native C/C++ stuff we need through the Android NDK, but without needing Makefiles and such. More details here:
http://code.google.com/p/javacpp/#Instructions_for_Android
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.
I've been running the Android SDK for a while now in Eclipse (MAC OSX). I've downloaded the NDK and installed the C/C++ tools in Eclipse, but could anyone guide me on using the NDK? For example, do I just create an Android project like normal and build it with the NDK instead?
Really could do with a decent tutorial if anyone know of any.
EDIT: OK so I have the NDK installed now (I think) but does anyone have any idea how to use it? I got as far as this (taken from here):
Run Terminal
cd ~/android-ndk-1.5_r1
make APP=hello-jni
In order to run the hello-jni sample application, but I get an error in terminal saying:
Android NDK: APP variable defined to
unknown applications: hellojni
Android NDK: You might want to use
one of the following:
build/core/main.mk:81: *** Android
NDK: Aborting . Stop.
Any ideas why?
As simply as I can describe it, building an Android app from within Eclipse that uses the NDK requires two steps.
First, inside your terminal you need to run the NDK build script on your project. cd into the root of your project directory and then execute the ndk-build script within that directory.
For example:
cd ~/workspace/hello-jni
./~/android-ndk-1.5_r1/ndk-build
After doing this, you should see some output that results in the creation of a *.SO file within the obj directory within your project directory.
Once you have the *.SO file, the final step to building an application with the Android NDK through Eclipse is to build it with Eclipse like you would any other application and then deploy it for testing.
If you make any changes to the C/C++ code you'll need to repeat step one and regenerate your *.SO file before building and deploying your application from within Eclipse again.
I would like to note that by using the Android NDK your android apps are still based upon Java. They're just communicating with code written in C/C++ by way of the Java Native Interface.
Finally, I am not aware of any Eclipse plugins that will aid with NDK development. Everything I know about the NDK I have learned the official Android NDK documentation. Please feel free to comment and let me know if there anything I can clear up in my response.
Native development and debugging support came into Eclipse environment as of ADT version 20. http://tools.android.com/recent/usingthendkplugin
Set path to NDK from Eclipse Preferences -> Android -> NDK
Right-click on your project and choose Android Tools -> Add Native Support
developer.android.com states you also need Cygwin.
http://developer.android.com/tools/sdk/ndk/index.html#Contents
Required development tools
For all development platforms, GNU Make 3.81 or later is required. Earlier versions of GNU Make might work but have not been tested.
A recent version of awk (either GNU Awk or Nawk) is also required.
For Windows, Cygwin 1.7 or higher is required. The NDK will not work with Cygwin 1.5 installations.
The docs directory in the NDK has some pretty good information on how to use the NDK itself. Read the overview, Application.mk, and Android.mk HTML docs. You'll want to google for the Sun JNI PDF, download it, and learn what JNI is all about before you go any further. This is because simply compiling a bunch of C/C++ code into libraries with the NDK is only part of the process. You have to write native Java code that calls your C/C++, and you have to create wrapper functions in C/C++ that adhere to JNI conventions that the native Java code can invoke. JNI has been around a long time, it's not Android specific by any means. So, you can, to learn about it, go quite far following tutorials geared towards JNI, using command line tools like javah and javac, and then return to integrating with the NDK after you know the basics. (For an example of what these C shims look like, take a look at the hello-jni sample in the NDK; the C source file there shows you typically what the shims look like. Using javah to generate these shims is the way to go, you create Java classes that have native methods, process them with javah, and it generates the C headers for you, then you code up C functions that adhere to the generated function prototypes).
Note: while the NDK docs would have you manually building from command line and then going into Eclipse to build your app (a laborious sequence of steps, to be sure, especially if you are changing the C/C++ code), it turns out you can integrate easily with Eclipse so that the NDK is run each time you build from Eclipse. To see how, read here.
This is for benefit of others who want to create the project from scratch from within eclipse: I followed steps mentioned here in this blog here and it works fine: http://mhandroid.wordpress.com/2011/01/23/using-eclipse-for-android-cc-development/
To attempt to answer the question directly - you need to run ndk-build in the folder with the native code within your project folder. This creates the .so files found in the file explorer/resources tree under jni in Eclipse. These functions, if the syntax in the code is correct, can now be called from your java code.
I found many sources of help when install and getting to grips with Android Developer Tools and the NDK. I wrote a blog post to share my experiences and hopefully give back to the community that helped me get there which may help understand my answer: http://workingmatt.blogspot.co.uk/2013/03/set-up-android-sdk-and-ndk.html