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How can I run python script in android studio with java [duplicate]

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We are working on an S60 version and this platform has a nice Python API..
However, there is nothing official about Python on Android, but since Jython exists, is there a way to let the snake and the robot work together??

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.
Kivy Showcase app

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.

Yes! : Android Scripting Environment
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
Pygame is a 2D game engine for Python (on desktop) that is popular with new programmers. The Pygame Subset for Android describes itself as...
...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.
API
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 Android object.
from android import Android
droid = Android()
droid.ttsSpeak('hello world') # example using the text to speech facade
Each language has pretty much the same API. You can even use the JavaScript API inside webviews.
let droid = new Android();
droid.ttsSpeak("hello from js");
User Interfaces
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
have.
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.
QPython
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.
Useful Links
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).

Termux
You can use the Termux app, which provides a POSIX environment for Android, to install Python.
Note that apt install python will install Python3 on Termux. For Python2, you need to use apt install python2.
Some demos: https://www.youtube.com/watch?v=fqqsl72mASE
The GitHub project: https://github.com/termux

Kivy
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.

Using SL4A (which has already been mentioned by itself in other answers) you can run a full-blown web2py instance (other python web frameworks are likely candidates as well). SL4A doesn't allow you to do native UI components (buttons, scroll bars, and the like), but it does support WebViews. A WebView is basically nothing more than a striped down web browser pointed at a fixed address. I believe the native Gmail app uses a WebView instead of going the regular widget route.
This route would have some interesting features:
In the case of most python web frameworks, you could actually develop and test without using an android device or android emulator.
Whatever Python code you end up writing for the phone could also be put on a public webserver with very little (if any) modification.
You could take advantage of all of the crazy web stuff out there: query, HTML5, CSS3, etc.

Not at the moment and you would be lucky to get Jython to work soon. If you're planning to start your development now you would be better off with just sticking to Java for now on.

QPython
I use the QPython app. It's free and includes a code editor, an interactive interpreter and a package manager, allowing you to create and execute Python programs directly on your device.

Here are some tools listed in official python website
There is an app called QPython3 in playstore which can be used for both editing and running python script.
Playstore link
Another app called Termux in which you can install python using command
pkg install python
Playstore Link
If you want develop apps , there is Python Android Scripting Layer (SL4A) .
The Scripting Layer for Android, SL4A, is an open source application that allows programs written in a range of interpreted languages to run on Android. It also provides a high level API that allows these programs to interact with the Android device, making it easy to do stuff like accessing sensor data, sending an SMS, rendering user interfaces and so on.
You can also check PySide for Android, which is actually Python bindings for the Qt 4.
There's a platform called PyMob where apps can be written purely in Python and the compiler tool-flow (PyMob) converts them in native source codes for various platforms.
Also check python-for-android
python-for-android is an open source build tool to let you package Python code into standalone android APKs. These can be passed around, installed, or uploaded to marketplaces such as the Play Store just like any other Android app. This tool was originally developed for the Kivy cross-platform graphical framework, but now supports multiple bootstraps and can be easily extended to package other types of Python apps for Android.
Try Chaquopy
A Python SDK for Android
Anddd... BeeWare
BeeWare allows you to write your app in Python and release it on multiple platforms. No need to rewrite the app in multiple programming languages. It means no issues with build tools, environments, compatibility, etc.

From the Python for android site:
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.

Chaquopy
Chaquopy is a plugin for Android Studio's Gradle-based build system. It focuses on close integration with the standard Android development tools.
It provides complete APIs to call Java from Python or Python from Java, allowing the developer to use whichever language is best for each component of their app.
It can automatically download PyPI packages and build them into an app, including selected native packages such as NumPy.
It enables full access to all Android APIs from Python, including the native user interface toolkit (example pure-Python activity).
This used to be a commercial product, but it's now free and open-source.
(I am the creator of this product.)

Yet another attempt: https://code.google.com/p/android-python27/
This one embed directly the Python interpretter in your app apk.

You can run your Python code using sl4a. sl4a supports Python, Perl, JRuby, Lua, BeanShell, JavaScript, Tcl, and shell script.
You can learn sl4a Python Examples.

You can use QPython:
It has a Python Console, Editor, as well as Package Management / Installers
http://qpython.com/
It's an open source project with both Python 2 and Python 3 implementations. You can download the source and the Android .apk files directly from github.
QPython 2: https://github.com/qpython-android/qpython/releases
QPython 3: https://github.com/qpython-android/qpython3/releases

Another option if you are looking for 3.4.2 or newer (3.9.6 as of this writing) is this archive on GitHub.
Python3-Android 3.4.2 or Python3-Android 3.9.6
I believe the original archive supports Python 3.4.2, the latest GRRedwings branch support 3.9.6 and the 22b version of the NDK. Older branches support other versions, but are not as easy to compile with docker.
The older version you simply clone the archive, run make and you get the .so or the .a
The newer versions follow the ReadMe, but it uses docker for consistent builds.
I currently use this to run raw Python on android devices. With a couple modifications to the build files you can also make x86 and armeabi 64 bit

Take a look at BeeWare. It has grown significantly. It is awarded with PSF (Python Software Foundation) Education Grant.
Beeware's aim is to be able to create native apps with Python for all supported operating systems, including Android.
Official Website: Beeware
Github Repo: https://github.com/beeware

Didn't see this posted here, but you can do it with Pyside and Qt now that Qt works on Android thanks to Necessitas.
It seems like quite a kludge at the moment but could be a viable route eventually...
http://qt-project.org/wiki/PySide_for_Android_guide

One more option seems to be pyqtdeploy which citing the docs is:
a tool that, in conjunction with other tools provided with Qt, enables
the deployment of PyQt4 and PyQt5 applications written with Python
v2.7 or Python v3.3 or later. It supports deployment to desktop
platforms (Linux, Windows and OS X) and to mobile platforms (iOS and
Android).
According to Deploying PyQt5 application to Android via pyqtdeploy and Qt5 it is actively developed, although it is difficult to find examples of working Android apps or tutorial on how to cross-compile all the required libraries to Android. It is an interesting project to keep in mind though!

Check out enaml-native which takes the react-native concept and applies it to python.
It lets users build apps with native Android widgets and provides APIs to use android and java libraries from python.
It also integrates with android-studio and shares a few of react's nice dev features like code reloading and remote debugging.

In-browser video (de)coding and processing

For our web app we need some (preferably) client side video processing.
I think of the following workflow:
ask a user for a video file
decode it
do some processing on selected frames
combine these frames to the new video
encode it
upload it to the server
play it to our users
Reasons to do this client side:
output video is much smaller, so we have to upload less
video processing is too costly for the server, we prefer to use client's CPU
It is OK to install something once but then everything should work as an ordinary web app.
I've spent few days googling, but it is just too much to digest. So I ask for help.
Here are my findings/assumptions/questions.
Is there a simple way to do it with Flash?
1.1. Can access user-selected file from local file system
1.2. Has some decoders built-in, but these are rather specific and do NOT cover common video formats
1.3. Can NOT use locally installed codecs
1.4. It is impractical to implement codecs in ActionScript, so there are no such libraries
1.5. Can process frames
1.6. Has built-in coder(s)
Is there a simple way to do it with Silverlight?
2.1. Can access user-selected file from local file system
2.2. Has some decoders built-in, but these are rather specific and do NOT cover common video formats
2.3. Can NOT use locally installed codecs from in-browser sandbox
2.4. Can bring external executable (ffmpeg) to the in-browser sandbox but can NOT run it
2.5. Can only use DLLs specifically built for Silverlight runtime inside in-browser sandbox, so ffmpeg proxy (COM?) and alikes are of NO use
2.6. Can be right-click-installed from web page and maybe #2.3, #2.4 or #2.5 will work, but this will NOT make on-page app work, user will need to run it separately outside browser
2.7. It is OK to implement codecs natively (port ffmpeg?), but I was not able to find such a pack
2.8. Can process frames
2.9. Has built-in coder(s)
Is there a simple way to do it with Java?
3.1. Can access user-selected file from local file system
3.2. JMF has basic codecs built-in
3.3. Jffmpeg could add more codecs
3.4. Can process frames
Is there something else that could do the job?
Looks like due to #1.2, #1.3 and #1.4 Flash is not an option.
Looks like Silverlight could do the trick if only there exists natively implemented codecs pack.
Java looks most promising.
Before diving into it I still want an answer about Flash (due to install base) and Silverlight (.NET already used in the project).
Please advice if my findings/assumptions/reasonings are correct.
Thank you.

Get Video file metadata in Java

I have been trying to find a way to get the metadata out of video files such as frame rate, length, codec, aspect ratio. What java libraries are out there that would be good for this?

You can use VLCJ (GPL license)
VLCJ wraps around libVLC DLL library (the library used in VLC) via JNA for Java app. It supports reading the metadata from a media file via MediaPlayer.getMediaMeta()
Take note: certain versions of VLCJ don't work in full functionality with certain versions of libVLC. For example, VLCJ 1.2.x only works perfectly well with libVLC 1.2.0 (which is not released yet - a nightly build at the moment). If you use it with libVLC 1.1.x, it won't be able to read media file metadata via MediaPlayer.getMediaMeta(). In this case, you need to get the correct libVLC library for VLCJ version you choose.
http://code.google.com/p/vlcj/wiki/WhichVersion
VLCJ 1.2.x has some design changes when compared to VLCJ 1.1.x which may frustrate seasoned developer of VLCJ but it is for the good reasons.

SVG processing under Java on Android and desktop

I am trying to write a Java application that will generate SVG image based on XML file. The application should also be able to show SVG file. My application should run on Android platform and desktop PCs. I read about Swing + Batik but afaik it will not work on Android. What is the best library to achieve this ?

This article in Code Project deals with the subject. Two approaches are presented:
android-libsvg library.
Anti Grain Geometry engine.
Both solutions have dependencies on native code library, so you would need JNI.
There is also svg4mobile project, which only uses Java.

per this thread: libsvg ported
libsvg has been ported to android..see thread for details. You need a crystax form of NDK, ie exceptions enabled..build/install doc here at:build-install-doc

Also try this open-source library, Apache 2.0 license:
SVG-Android
Performance is good as the actual drawing is handled natively by an android.graphics.Picture object.

Java Media Framework on client side?

If I’m writing an applet that shows a video sequence (eg. streaming from a camera, or the applet itself is running the on the camera), do my clients need to download the Java Media Framework libraries inorder to see the sequence?

They need to install Java Media Framework on their computers, or you'll need to bundle the JMF together with your applet somehow.

If the applet makes use of the JMF libraries they need to be downloaded to the client machine (where the applet executes). However, JMF gets very little development from Sun (read none) and is pretty much legacy now (subjective).
Depending on how modern the camera is and what codecs it can output it may also be worth considering the video support in either javafx of flash.

Distributing the JMF.jar with your applet is sufficient.

Create a JAR ( Java DLL ) and put all the jar files from the install directory, JMF is 32-bit only, so the x86\java\JMF2.1.1e\lib is where it's usually located.
If you customized the customizer.jar you want that one too.
You can download it from a server like an applet and embed the applet inside and then run it. It's worked for me for 14+ years in Adult Pay sites.

Did you consider to use Java FX? This technology is dealing with this problem of downloading media libraries and so no. Of course. It is still in development. If to be first-adopter is option, it will be worth of considering this.