b"Exception in connect function: Class not found b'org/jnius/NativeInvocationHandler'" when trying to use camera module

[tomgold182]

after applying @franccisco's #520 fix, i am getting this error when trying to access the camera with camera.take_picture:
b"Exception in connect function: Class not found b'org/jnius/NativeInvocationHandler'"

[ghost]

Thanks for testing the PR and posting your results. To figure out what's going on, I need some info:

1. What's your kivy and pyjnius version?
2. Please, paste a more detailed log. I'd like to know what else is crashing.

[tomgold182]

I am using kivy 1.8.0
following some blog post on this issue,
i added this line
autoclass('org.jnius.NativeInvocationHandler')
on my main thread and it seems to be solving this issue ,
but then leads to this:

Exception in connect function: Class not found b'org/kivy/android/PythonActivity$ActivityResultListener'

there no more information in the logs, just the line i sent you. is there a way to get a more detailed log?

[tomgold182]

pyjnius seems to be 1.2.0

[tshirtman]

python for android currently pins pyjnius to commit 6553ad4 which is the next commit after 1.2.0, it hasn't been tried with the newer 1.2.1 release of pyjnius yet.
https://github.com/kivy/python-for-android/blob/2610330cfca7f43d2fa69e175f4b9c3d09338680/pythonforandroid/recipes/pyjnius/__init__.py#L11

[tomgold182]

@tshirtman I tried the official version also. Same issue, that's why i have tried to change.

[tshirtman]

I'm looking into building/using latest pyjnius with android, at the moment it's not possible. I'm not sure this would solve this particular issue, but it would maybe help finding the cause and fixing it.

[tshirtman]

I couldn't get the NativeInvocationHandler issue reproduced, but i couldn't get a picture either, i think the plyer's code is obsolete, so i looked into ways to get it up to current apis, but couldn't get the result picture from java to kivy, https://gist.github.com/4bf8fdf745eb4a961b0f83066fe6a8d3 if anyone wants to have a look, sorry, this is not exactly beautiful code, as i tried different things and kept things that were nearly working commented just in case.

This is using latest pyjnius, with a slight update to the recipe to get it to build, but i don't think it's related. kivy/python-for-android#2036 i created a pull request, you can use these files as a local recipe if you want to try with latest pyjnius.

[tomgold182]

@tshirtman Thanks!
So you are suggesting using pyjnius directly instead of plyer?

[tshirtman]

Once a working and reliable method is found, it can be generalized again and put inside plyer, for now, it's just easier to experiment with pyjnius direclty to find that method.

[Fak3]

For the camera to work, one has to add an android fileprovider to solve #500. The PR for that is kivy/python-for-android#1922 but unfortunately I could not find time to document its usage yet.

[tomgold182]

@Fak3 any updates about that ? how can I manually apply your fix?

[Fak3]

@Fak3 any updates about that ? how can I manually apply your fix?

You can checkout git branch from that pr somwhere, then launch setup.py install in that dir to install p4a. Then you can create your fileprovider xml file in your app dir, and build your app as described in the pr

[tomgold182]

@Fak3 is that already in main ?