Python for Android
Python for android is a project to create your own Python distribution including the modules you want, and create an apk including python, libs, and your application.
In terms of comparaison, you can check how Python for android can be useful compared to other projects.
|Project||Native Python||GUI libraries||APK generation||Custom build|
|Python for android||Yes||Yes||Yes||Yes|
|Python on a chip||No||No||No||No|
For the moment, we are shipping only one "java bootstrap" needed for decompressing all the files of your project, create an OpenGL ES 2.0 surface, handle touch input and manage an audio thread.
If you want to use it without kivy module (an opengl es 2.0 ui toolkit), then you might want a lighter java bootstrap, that we don't have right now. Help is welcome :)
WARNING: the current version is working only on Ubuntu oneiric (11.10). We don't provide support on other platform. If it doesn't work, send us patch, not bug report.
You need the minimal environment for building python. Note that other libraries might need other tools:
sudo apt-get install build-essential patch git-core ccache
You must have android SDK and NDK. You can download them at:
If it's your very first time into android SDK, don't forget to follow documentation for recommended components at:
http://developer.android.com/sdk/installing.html#which You need to download at least one platform into your environment, so that you will be able to compile your application and set up an Android Virtual Device (AVD) to run it on (in the emulator). To start with, just download the latest version of the platform. Later, if you plan to publish your application, you will want to download other platforms as well, so that you can test your application on the full range of Android platform versions that your application supports.
After installing them, export both installation path, NDK version and API to use:
export ANDROIDSDK=/path/to/android-sdk export ANDROIDNDK=/path/to/android-ndk export ANDROIDNDKVER=rX export ANDROIDAPI=X # example export ANDROIDSDK="/home/tito/code/android/android-sdk-linux_86" export ANDROIDNDK="/home/tito/code/android/android-ndk-r7" export ANDROIDNDKVER=r7 export ANDROIDAPI=14
Step 1: compile the toolchain
If you want to compile the toolchain with only kivy module:
./distribute.sh -m "kivy"
After a long time, you'll get a "dist/default" directory containing all the compiled libraries and build.py script to package your application using thoses libraries.
You can include other libraries to compile using -m:
./distribute.sh -m "openssl kivy" ./distribute.sh -m "pil ffmpeg kivy"
Available options to distribute.sh:
-d directory Name of the distribution directory -h Show this help -l Show a list of available modules -m 'mod1 mod2' Modules to include -f Restart from scratch (remove the current build)
Step 2: package your application
Go fo your custom python distribution:
Use the build.py for creating the APK:
./build.py --package org.test.touchtracer --name touchtracer \ --version 1.0 --dir ~/code/kivy/examples/demo/touchtracer debug
Then, the android package (APK) will be generated at:
Available options to build.py:
-h, --help show this help message and exit --package PACKAGE The name of the java package the project will be packaged under. --name NAME The human-readable name of the project. --version VERSION The version number of the project. This should consist of numbers and dots, and should have the same number of groups of numbers as previous versions. --numeric-version NUMERIC_VERSION The numeric version number of the project. If not given, this is automatically computed from the version. --dir DIR The directory containing public files for the project. --private PRIVATE The directory containing additional private files for the project. --launcher Provide this argument to build a multi-app launcher, rather than a single app. --icon-name ICON_NAME The name of the project's launcher icon. --orientation ORIENTATION The orientation that the game will display in. Usually one of "landscape" or "portrait". --permission PERMISSIONS The permissions to give this app. --ignore-path IGNORE_PATH Ignore path when building the app --icon ICON A png file to use as the icon for the application. --presplash PRESPLASH A jpeg file to use as a screen while the application is loading. --install-location INSTALL_LOCATION The default install location. Should be "auto", "preferExternal" or "internalOnly". --compile-pyo Compile all .py files to .pyo, and only distribute the compiled bytecode. --blacklist BLACKLIST Use a blacklist file to match unwanted file in the final APK
How does it work ?
To be able to run Python on android, you need to compile it for android. And you need to compile all the libraries you want for android too. Since Python is a language, not a toolkit, you cannot draw any user interface with it: you need to use a toolkit for it. Kivy can be one of them.
So for a simple ui project, the first step is to compile Python + Kivy + all others libraries. Then you'll have what we call a "distribution". A distribution is composed of:
- Python libraries
- All selected libraries (kivy, pygame, pil...)
- A java bootstrap
- A build script
You'll use the build script for create an "apk": an android package.
Customize your distribution
The basic layout of a distribution is:
AndroidManifest.xml - (*) android manifest (generated from templates) assets/ private.mp3 - (*) fake package that will contain all the python installation public.mp3 - (*) fake package that will contain your application bin/ - contain all the apk generated from build.py blacklist.txt - list of file patterns to not include in the APK buildlib/ - internals libraries for build.py build.py - build script to use for packaging your application build.xml - (*) build settings (generated from templates) default.properties - settings generated from your distribute.sh libs/ - contain all the compiled libraries local.properties - settings generated from your distribute.sh private/ - private directory containing all the python files lib/ this is where you can remove or add python libs. python2.7/ by default, some modules are already removed (tests, idlelib, ...) project.properties - settings generated from your distribute.sh python-install/ - the whole python installation, generated from distribute.sh not included in the final package. res/ - (*) android resource (generated from build.py) src/ - Java bootstrap templates/ - Templates used by build.py (*): Theses files are automatically generated from build.py, don't change them directly !
List of available modules: jpeg pil png sdl sqlite3 pygame kivy android libxml2 libxslt lxml ffmpeg openssl chipmunk
The up-to-date list is available at: https://github.com/kivy/python-for-android/tree/master/recipes
Only hostpython and python are 2 mandatory recipes, used for building hostpython / target python libraries.
Create your own recipes
A recipe is a script that contain the "definition" of a module to compile. The directory layout of a recipe for a <modulename> is something like:
python-for-android/recipes/<modulename>/recipe.sh python-for-android/recipes/<modulename>/patches/ python-for-android/recipes/<modulename>/patches/fix-path.patch
When building, all the recipe build must go to:
For example, if you want to create a recipe for sdl, do:
cd python-for-android/recipes mkdir sdl cp recipe.sh.tmpl sdl/recipe.sh sed -i 's#XXX#sdl#' sdl/recipe.sh
Then, edit the sdl/recipe.sh to adjust other information (version, url) and complete build function.
- PGS4A: http://pygame.renpy.org/
- Android scripting: http://code.google.com/p/android-scripting/
- Python on a chip: http://code.google.com/p/python-on-a-chip/
- jni/Android.mk must not include ttf/image/mixer if not asked by the user
- Python try always to import name.so, namemodule.so, name.py, name.pyo ?
- restore libpymodules.so loading to reduce the number of dlopen.