Solving problem is about exposing yourself to as many situations as possible like Is there a way to run Python on Android? and practice these strategies over and over. With time, it becomes second nature and a natural way you approach any problems in general. Big or small, always start with a plan, use other strategies mentioned here till you are confident and ready to code the solution.
In this post, my aim is to share an overview the topic about Is there a way to run Python on Android?, which can be followed any time. Take easy to follow this discuss.
One way is to use Kivy:
Open source Python library for rapid development of applications
that make use of innovative user interfaces, such as multi-touch apps.
Kivy runs on Linux, Windows, OS X, Android and iOS. You can run the same [python] code on all supported platforms.
There is also the new Android Scripting Environment (ASE/SL4A) project. It looks awesome, and it has some integration with native Android components.
Note: no longer under “active development”, but some forks may be.
An example via Matt Cutts via SL4A — “here’s a barcode scanner written in six lines of Python code:
import android droid = android.Android() code = droid.scanBarcode() isbn = int(code['result']['SCAN_RESULT']) url = "http://books.google.com?q=%d" % isbn droid.startActivity('android.intent.action.VIEW', url)
Pygame Subset for Android
…a port of a subset of Pygame functionality to the Android platform. The goal of the project is to allow the creation of Android-specific games, and to ease the porting of games from PC-like platforms to Android.
The examples include a complete game packaged as an APK, which is pretty interesting.
As a Python lover and Android programmer, I’m sad to say this is not a good way to go. There are two problems:
One problem is that there is a lot more than just a programming language to the Android development tools. A lot of the Android graphics involve XML files to configure the display, similar to HTML. The built-in java objects are integrated with this XML layout, and it’s a lot easier than writing your code to go from logic to bitmap.
The other problem is that the G1 (and probably other Android devices for the near future) are not that fast. 200 MHz processors and RAM is very limited. Even in Java, you have to do a decent amount of rewriting-to-avoid-more-object-creation if you want to make your app perfectly smooth. Python is going to be too slow for a while still on mobile devices.
Scripting Layer for Android
SL4A does what you want. You can easily install it directly onto your device from their site, and do not need root.
It supports a range of languages. Python is the most mature. By default, it uses Python 2.6, but there is a 3.2 port you can use instead. I have used that port for all kinds of things on a Galaxy S2 and it worked fine.
SL4A provides a port of their
android library for each supported language. The library provides an interface to the underlying Android API through a single
from android import Android droid = Android() droid.ttsSpeak('hello world') # example using the text to speech facade
let droid = new Android(); droid.ttsSpeak("hello from js");
For user interfaces, you have three options:
- You can easily use the generic, native dialogues and menus through the
API. This is good for confirmation dialogues and other basic user inputs.
- You can also open a webview from inside a Python script, then use HTML5
for the user interface. When you use webviews from Python, you can pass
messages back and forth, between the webview and the Python process that
spawned it. The UI will not be native, but it is still a good option to
- There is some support for native Android user interfaces, but I am not
sure how well it works; I just haven’t ever used it.
You can mix options, so you can have a webview for the main interface, and still use native dialogues.
There is a third party project named QPython. It builds on SL4A, and throws in some other useful stuff.
QPython gives you a nicer UI to manage your installation, and includes a little, touchscreen code editor, a Python shell, and a PIP shell for package management. They also have a Python 3 port. Both versions are available from the Play Store, free of charge. QPython also bundles libraries from a bunch of Python on Android projects, including Kivy, so it is not just SL4A.
Note that QPython still develop their fork of SL4A (though, not much to be honest). The main SL4A project itself is pretty much dead.
- SL4A Project (now on GitHub): https://github.com/damonkohler/sl4a
- SL4A Python 3 Port: https://code.google.com/p/python-for-android/wiki/Python3
- QPython Project: http://qpython.com
- Learn SL4A (Tutorialspoint): https://www.tutorialspoint.com/sl4a/index.htm
Cross-Compilation & Ignifuga
My blog has instructions and a patch for cross compiling Python 2.7.2 for Android.
I’ve also open sourced Ignifuga, my 2D Game Engine. It’s Python/SDL based, and it cross compiles for Android. Even if you don’t use it for games, you might get useful ideas from the code or builder utility (named Schafer, after Tim… you know who).
I wanted to add to what @JohnMudd has written about Kivy. It has been years since the situation he described, and Kivy has evolved substantially.
The biggest selling point of Kivy, in my opinion, is its cross-platform compatibility. You can code and test everything using any desktop environment (Windows/*nix etc.), then package your app for a range of different platforms, including Android, iOS, MacOS and Windows (though apps often lack the native look and feel).
With Kivy’s own KV language, you can code and build the GUI interface easily (it’s just like Java XML, but rather than TextView etc., KV has its own
ui.widgets for a similar translation), which is in my opinion quite easy to adopt.
Currently Buildozer and python-for-android are the most recommended tools to build and package your apps. I have tried them both and can firmly say that they make building Android apps with Python a breeze. Their guides are well documented too.
iOS is another big selling point of Kivy. You can use the same code base with few changes required via kivy-ios Homebrew tools, although Xcode is required for the build, before running on their devices (AFAIK the iOS Simulator in Xcode currently doesn’t work for the x86-architecture build). There are also some dependency issues which must be manually compiled and fiddled around with in Xcode to have a successful build, but they wouldn’t be too difficult to resolve and people in Kivy Google Group are really helpful too.
With all that being said, users with good Python knowledge should have no problem picking up the basics quickly.
If you are using Kivy for more serious projects, you may find existing modules unsatisfactory. There are some workable solutions though. With the (work in progress) pyjnius for Android, and pyobjus, users can now access Java/Objective-C classes to control some of the native APIs.