app crash on close

[jligeza]

When I exit my app (app.stop()), a strange segmentation error occurs: http://pastebin.com/F8HEaeip

This is with sdl2 and kivy 1.9.2 dev.
It works fine with pygame, what makes me puzzled.

The requirements list:
requirements = openssl,geopy,plyer,android,tinydb,hostpython2,kivy==master

What could be the reason of this crash?

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[inclement]

I don't have any insight into this, I guess it needs some active debugging. If the segfault is happening during kivy's internal stop process then that's probably the first place to look.

[cidermole]

Here's the problem I experienced (with crash in the same place):

Nobody destroys the app Window by default. Then long after Python is gone ("Python for android ended."), Java will call back via Activity.onPause() into SDL native code, which then references a stale Android_Window in Java_org_libsdl_app_SDLActivity_nativePause().

Workaround:

You must call WindowSDL.close() before the app exits the main EventLoop.

An ideal way to do this is to handle the event in App.on_stop():

from kivy.app import App
from kivy.core.window import Window

class MyFancyApplication(App):
    def on_stop(self):
        Window.close()

# ...

# somewhere else:
App.get_running_app().stop()

[cidermole]

@inclement can you provide details about the basic kivy shutdown design? I guess that the event should be bound to something which cleans up the window without needing user code?

[gooroopy]

@cidermole I've also spent a few hours to fixed this issue a couple week ago, this is my patch :- http://pastebin.com/JthasWiG

@inclement I will submit PR to Kivy if this is make sense.

[inclement]

@gooroopy Sorry for the delay replying, and thanks a lot for the patch! I'm not familiar with this part of Kivy's internals, but if you didn't do so already it would be very welcome to open a PR in the kivy repo for it.

[inclement]

I believe this is no longer happening on p4a master. Recently I was testing this type of thing while getting pause to work with sdl2.0.9