Scripting Layer For Android

Introduction

Originally authored by Damon Kohler, Scripting Layer for Android, SL4A, is an automation toolset for calling Android APIs in a platform-independent manner. It supports both remote automation via ADB as well as execution of scripts from on-device via a series of lightweight translation layers.

Build Instructions

Due to its inclusion in AOSP as a privileged app, building SL4A requires a system build.

For the initial build of Android:

cd <ANDROID_SOURCE_ROOT>
source build/envsetup.sh
lunch aosp_<TARGET>
make [-j15]

where <ANDROID_SOURCE_ROOT> is the root directory of the android tree and <TARGET> is the lunch target name

Then Build SL4A:

cd <ANDROID_SOURCE_ROOT>/external/sl4a
mm [-j15]

Adding SL4A Builds to Android Builds by Default

  1. If you are not using a custom buildspec, create one as follows:

     cp <ANDROID_SOURCE_ROOT>/build/buildspec.mk.default <ANDROID_SOURCE_ROOT>/buildspec.mk

  2. Modify the buildspec to build SL4A as a custom module by editing the line '#CUSTOM_MODULES:=' to 'CUSTOM_MODULES:=sl4a':

     sed -i 's/#CUSTOM_MODULES:=/CUSTOM_MODULES:=sl4a/' <ANDROID_SOURCE_ROOT>/buildspec.mk

Install Instructions

Run the following command:

adb install -r <ANDROID_SOURCE_ROOT>/out/target/product/<TARGET>/data/app/sl4a/sl4a.apk

Run Instructions

a) SL4A may be launched from Android as a normal App; or
b) To enable RPC access from the command prompt:

adb forward tcp:<HOST_PORT_NUM> tcp:<DEVICE_PORT_NUM>
adb shell "am start -a com.googlecode.android_scripting.action.LAUNCH_SERVER \
           --ei com.googlecode.android_scripting.extra.USE_SERVICE_PORT <DEVICE_PORT_NUM> \
           com.googlecode.android_scripting/.activity.ScriptingLayerServiceLauncher"

where <HOST_PORT_NUM> and <DEVICE_PORT_NUM> are the tcp ports on the host computer and device.

Generate the API Documentation

From SL4A source directory run this command:

    python Docs/generate_api_reference_md.py

In the Docs directory there should now be an ApiReference.md file that contains which RPC functions are available in SL4A as well as documentation for the RPC functions.