kivy hello world not working in Ubuntu 18.04.3, python3, virtualbox, kivy 1.11.1

I’m getting an error with the hello world example on the kivy.org front page. All basic packages are installed on plain vanilla Ubuntu. The PPA provides the latest stable build and I’ve got the updated kivy version v1.11.1 on Ubuntu 18.04.3.

The hello world on kivy.org front page should work in plain vanilla Ubuntu in Virtualbox 6.0 with 3D graphics accerleration turned OFF.

What’s the deal?

Thank youuuuuuu

Versions

• Python: 3.6.8
• OS: Ubuntu 18.04.3
• Kivy: v1.11.1
• Kivy installation method: sudo add-apt-repository ppa:kivy-team/kivy, then sudo apt-get install python3-kivy

Description

I’m getting this error: [CRITICAL] [Window ] Unable to find any valuable Window provider.

---

Code

from kivy.app import App
from kivy.uix.button import Button

class TestApp(App):
    def build(self):
        return Button(text='Hello World')

TestApp().run()

Log

[INFO   ] [Logger      ] Record log in /home/user/.kivy/logs/kivy_19-09-03_11.txt
[INFO   ] [Kivy        ] v1.11.1
[INFO   ] [Kivy        ] Installed at "/usr/lib/python3/dist-packages/kivy/__init__.py"
[INFO   ] [Python      ] v3.6.8 (default, Jan 14 2019, 11:02:34) 
[GCC 8.0.1 20180414 (experimental) [trunk revision 259383]]
[INFO   ] [Python      ] Interpreter at "/usr/bin/python3"
[INFO   ] [Factory     ] 184 symbols loaded
[INFO   ] [Image       ] Providers: img_tex, img_dds, img_pil, img_gif (img_sdl2, img_ffpyplayer ignored)
[INFO   ] [Text        ] Provider: pil(['text_sdl2'] ignored)
[CRITICAL] [Window      ] Unable to find any valuable Window provider. Please enable debug logging (e.g. add -d if running from the command line, or change the log level in the config) and re-run your app to identify potential causes
egl_rpi - ImportError: cannot import name 'bcm'
  File "/usr/lib/python3/dist-packages/kivy/core/__init__.py", line 63, in core_select_lib
    fromlist=[modulename], level=0)
  File "/usr/lib/python3/dist-packages/kivy/core/window/window_egl_rpi.py", line 12, in <module>
    from kivy.lib.vidcore_lite import bcm, egl

sdl2 - ImportError: libSDL2_image-2.0.so.0: cannot open shared object file: No such file or directory
  File "/usr/lib/python3/dist-packages/kivy/core/__init__.py", line 63, in core_select_lib
    fromlist=[modulename], level=0)
  File "/usr/lib/python3/dist-packages/kivy/core/window/window_sdl2.py", line 27, in <module>
    from kivy.core.window._window_sdl2 import _WindowSDL2Storage

x11 - ModuleNotFoundError: No module named 'kivy.core.window.window_x11'
  File "/usr/lib/python3/dist-packages/kivy/core/__init__.py", line 63, in core_select_lib
    fromlist=[modulename], level=0)

[CRITICAL] [App         ] Unable to get a Window, abort.

[Levitanus]

actually, it would be great to update the installation section in docs at first.

[comperem]

hello, yes, the problem seems to be a missing apt-get dependency when installing the python3-kivy package.

From the Ubuntu installation instructions it appears the only install step for python3 is this:

sudo apt-get install python3-kivy

That command completes successfully and installs (or requires) the package libsdl2-2.0-0 which is the SDL2 library. This is necessary but incomplete.

The python3-sdl2 dependency should also be included to provide the python bindings to the libsdl2 library. So, following the first apt-get installation line with:

sudo apt-get install python3-sdl2

installs the remaining necessary packages and the hello, world example from kivy.org’s front page works once again.

For what it’s worth, the libsdl2-image-2.0-0 package was the single package that seemed to cause the hello, world example to fail. This package was a dependency on the python3-sdl2 installation but curiously was not removed with the removal of python3-sdl2.

There were several other dependent packages installed with the python3-sdl2 package and the libsdl2-image-2.0-0 package just happened to be the make-it-or-break-it package on my plain vanilla install to test the hello, world example.

My final conclusion is this seems to be an apt package dependency issue for python3. I don’t know how to convey this to the right people other than posting here.

Can someone make the proper reporting connections to the development team?