kivy 和 python3 在 ubuntu 18.04 上不起作用

Question

I have laptop with ubuntu 18.04 and i use for programming in python3. I decided to learn how i can make GUI and i chosen Kivy because of its multi-platform feature. After adding Kivy ppa and installing python3-kivy package with apt i tried to test the simple example with one button in the first page of kivy.org but it return this errors:

screenshot from my terminal

after that i installed python-kivy package for python2 and run this test file again but this time there is no problem and the GUI showed correctly.

the program runs correctly

now i can use python2 but i always use python3 before and i want to use it with kivy. Can anyone tell me why this problem happens?

Answer 1

Solution for me was, with Python 3.6.5

Uninstall everything:

sudo apt-get remove --purge python3-kivy
sudo pip3 uninstall cython kivy
sudo apt autoremove

Then:

sudo pip3 install Cython==0.28.2
sudo pip3 install https://github.com/kivy/kivy/archive/master.zip

or in case you need version 1.9.1

sudo pip3 install Cython==0.23
sudo pip3 install kivy==1.9.1

Answer 2

This bug, which I confirmed in Ubuntu 18.04, is probably the reason why python3-kivy was dropped from the default Ubuntu repositories in Ubuntu 19.04. This bug has been fixed and python3-kivy has been restored to the default Ubuntu repositories in Ubuntu 19.10 and later.

A later version of Kivy 1.11.1 (instead of 1.9.1 in Ubuntu 18.04) can be installed with python3 -m pip install kivy in a Python virtual environment using Python 3 virtual environment creator ( python3-virtualenv ) from the default Ubuntu repositories. Try running python3 -m pip install --upgrade pip before python3 -m pip install kivy to upgrade your pip3 to the latest version as I did.

Below are the results of running this Hello World test program with Kivy 1.11.1 in a Python 3 virtual environment. The Python 3 code ran without any errors, detected OpenGL and my NVIDIA proprietary graphics driver, and output this window:

Answer 3

Note that at this time the support for android python3 kivy is experimental. Even though you may create the .apk chances are it will not work.