Launch an SL4A script from an SL4A script

Question

I would like to start a background SL4A script (on a remote device) from within a different SL4A script. I can launch a script from a terminal by running something like this:

$ am start -a \
com.googlecode.android_scripting.action.LAUNCH_BACKGROUND_SCRIPT -n \
com.googlecode.android_scripting/.activity.ScriptingLayerServiceLauncher -e \
com.googlecode.android_scripting.extra.SCRIPT_PATH /sdcard/sl4a/scripts/main.py

I can't translate this into a startActivity call in Python.

The answer to a different question on opening a Twitter client works nicely, but I don't know how to extend that code. For example, how would you add a script path, and where would you put the line com.googlecode.android_scripting/.activity.ScriptingLayerServiceLauncher?

Answer 1

After many, many failed attempts, I now have this working in Ruby - I had an easier time generating the JSON extras this way than in Python.

Important! In the command-line version, you call on "com.googlecode.android_scripting/.activity.ScriptingLayerServiceLauncher"

From within a script, this is called as "com.googlecode.android_scripting.activity.ScriptingLayerServiceLauncher", without the slash. Leaving in the slash crashes sl4a.

[code]

require 'android' require 'json/pure'

d=Android.new

script = '/sdcard/sl4a/scripts/YOUR_SCRIPT'

data = {"com.googlecode.android_scripting.extra.SCRIPT_PATH"=>script}

extras = JSON.generate(data)

d.startActivity('com.googlecode.android_scripting.action.LAUNCH_BACKGROUND_SCRIPT','','',data,true,'com.googlecode.android_scripting','com.googlecode.android_scripting.activity.ScriptingLayerServiceLauncher')

[/code]

I hope this helps!

Answer 2

This function will launch any SL4A script from inside another one.

The first argument should be a path to the script you want to launch. The script can be in any language you have an interpreter installed for.

The second argument is optional and should be a bool. It defaults to False. It controls whether the terminal will be visible, so you can see output and errors. It does not effect whether the script has a UI or not.

from android import Android
droid = Android()

def launch_script(path, visible=False):

    visibilty   = 'FORE' if visible else 'BACK'
    activity    = 'com.googlecode.android_scripting.action.LAUNCH_{0}GROUND_SCRIPT'.format(visibilty)
    extras      = {'com.googlecode.android_scripting.extra.SCRIPT_PATH': path}
    packagename = 'com.googlecode.android_scripting'
    classname   = 'com.googlecode.android_scripting.activity.ScriptingLayerServiceLauncher'
    intent      = droid.makeIntent(activity, None, None, extras, None, packagename, classname).result

    droid.startActivityIntent(intent)

There's a gist for this code here.