autoclass: Class only found when called in specific places?

[cathay]

Versions

• Python: 3.8
• OS: Android 9
• Kivy: 1.11.1
• OpenJDK: 1.8

Description

I tried to use ffprobe in my helper.py as:

def get_video_length(filename):
    ffprobe = autoclass('com.arthenica.mobileffmpeg.FFprobe')
    config = autoclass('com.arthenica.mobileffmpeg.Config')
    ....

We got the error jnius.jnius.JavaException: Class not found b'com/arthenica/mobileffmpeg/FFprobe'. The fix for it is put
ffprobe = autoclass('com.arthenica.mobileffmpeg.FFprobe') in __init__.py but it seems not straightforward to me. I would like to get some thoughts on it.

get_video_length was called on different thread from main thread

buildozer.spec

android.gradle_dependencies = com.arthenica:mobile-ffmpeg-full:4.3.2

ffmpeg repository: https://github.com/tanersener/mobile-ffmpeg

Command:

buildozer --verbose android debug deploy run

[RobertFlatt]

Hmm, interesting....

All the examples show autoclass calls that are global (and probably more to the point static)
So perhaps it matters when autoclass happens?
The usage shown here is local, moving it to __init__.py would make it global.

And while digging I found this, which may be also be interesting
https://pyjnius.readthedocs.io/en/stable/api.html#pyjnius-and-threads

[praaggg]

In my case the build itself fails while using below in spec file
android.gradle_dependencies = com.arthenica:mobile-ffmpeg-full:4.3.2

[dbnicholson]

I think the issue is most likely that you're trying to resolve the class from a new native thread. See #2533 for details.

[Julian-O]

@cathay Was this resolved by the comment above?

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