Support multiple platforms

[lukpueh]

Our gradle file is currently configured to build for armeabi-v7a only, i.e. ARM CPU with 32-bit instruction set.

It would be great to support additional architectures, above all ARM/64-bit (which seems to become more and more popular). Here is a list of all supported ABIs.

Building a fat binary that targets multiple architectures should be as easy as adding the desired ABIs to the right line in build.gradle.

Additionally, and this is where it gets tricky, we need a libpython2.7.so for each desired ABI.

Since cross-compling Python for Android is everything but straight-forward I created an example app using kivy's python-for-android, extracted the generated libpython2.7.so and copied it together with the header files into our app.

Back then a quick try to build for anything else but armeabi-v7a failed. It would be worth to try again.

[JustinCappos]

Can you add some more info about how it actually failed? What was the error / problem?

[lukpueh]

Unfortunately not. I greped through my notes but I only jotted down something like: "Tried with --arch=x86, failed, will try later".

Also, the sample app I used back then does not work anymore with current SDK/NDK/p4a versions. I guess the most straight-forward approach, for someone you wants to take care of this ticket, is to go through the kivy docs (link above), copy-paste a new sample app and try again.

[aaaaalbert]

Re the @kivy/python-for-android build process: After updating the NDK to r13b, the following --archs work for me:

• armeabi-v7a (which is what we target for currently)
• arm64-v84
• x86
• x86_64

Neither of the mipses work however, despite the NDK containing populated platforms/android-21/arch-mips* dirs.

Output:

~$ p4a apk --arch=mips --private=/home/lukas/kivy-app --package=org.example.myapp --name "My app" --version 0.1 --requirements=python2,libffi --sdk_dir=$HOME/Android/Sdk --ndk_dir=$HOME/android-ndk-r13b --android_api=21 --ndk_ver=r13b
[INFO]:    This python-for-android revamp is an experimental alpha release!
[INFO]:    It should work (mostly), but you may experience missing features or bugs.
[WARNING]: Asked to compile for no Archs, so failing.

[fmetzger]

TBH, only the two ARM targets are probably of any actual relevance.
AFAIK there might not be a single MIPS Android device currently on the market. x86 might be a bit more interesting, but only marginally. There are one or two actual devices in the wild, as well as projects like Android-x86 or being able to port to Chrome OS (though i don't know any details on that process).

[aaaaalbert]

Thanks for the insight. If I remember correctly, we did indeed have a hard time sourcing non-ARM Android handhelds for the lab.