main window jumps up and down

[Fak3]

p4a version: develop branch

I have built simple kivy app with sdl2 backend, and it looks like window is changing height each 0.5 seconds from full screen to a bit smaller. So the whole app constantly jumps up and down.

adb log: https://gist.github.com/Fak3/ce144578c74762fc39f8f26c34590bb1

[Fak3]

Suspicious thing from the log, that right before I killed the app, it reported it's height slightly lower than device height:
V/SDL (13995): Window size: 1080x1845
V/SDL (13995): Device size: 1080x1920
But before that, after app is started, it reports that both are equal

[Fak3]

The latest sdl2 from hg fixes this bug. The bad news is that it does not work with multisamples. So you have to disable it in kivy config:

from kivy.config import Config
Config.set('graphics', 'multisamples', '0')

[inclement]

Any idea what has caused you to come across this issue? I don't think I've seen it mentioned before.

[Fak3]

It happens with any app if multisamples is enabled. I have reported in sdl bugtracker: https://bugzilla.libsdl.org/show_bug.cgi?id=4691

[Fak3]

Update: the kivy changeset mentioned below while probably related, does not seem to do anything wrong. Rather the bug was introduced after 2.0.9 in SDL repo, as it is reproduced in pure C SDL app.

i think it was introduced wit this commit: kivy/kivy@e437dfc
but cant;t test it, as kivy from this time fails to start with error:

06-25 18:08:35.966 I/python  ( 5717):  Traceback (most recent call last):
06-25 18:08:35.966 I/python  ( 5717):    File "/home/z/pproj/paradox_dev/main.py", line 41, in <module>
06-25 18:08:35.966 I/python  ( 5717):    File "/home/z/pproj/paradox_dev/label.py", line 4, in <module>
06-25 18:08:35.966 I/python  ( 5717):    File "/home/u1/.local/share/python-for-android/build/python-installs/paradox/kivy/uix/label.py", line 286, in <module>
06-25 18:08:35.966 I/python  ( 5717):    File "/home/u1/.local/share/python-for-android/build/python-installs/paradox/kivy/core/text/__init__.py", line 90, in <module>
06-25 18:08:35.966 I/python  ( 5717):  ImportError: cannot import name 'USE_PANGOFT2' from 'kivy.setupconfig' (/data/data/org.spbelect.paradox2/files/app/_python_bundle/site-packages/kivy/setupconfig.pyc)

[Fak3]

Oh! When app is built with --window option, it behaves normally and does not jump.

The key is to have both multisampling and SDL_WINDOW_FULLSCREEN flag.

[Julian-O]

Closing as no action required by p4a team.

If you disagree, please let us know.