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Qt app UI elements randomly rendered as blank/black in Docker

  • I prepared Dockerfile to build Docker image of my Qt application. To run the application I use X - I enable access to X server (xhost +local:root) , then I use the following command to run it:

    docker run -it --env="DISPLAY" --env="QT_X11_NO_MITSHM=1" \
        --volume="/tmp/.X11-unix:/tmp/.X11-unix:rw" mindforger:latest mindforger

    The problem is that some Qt UI elements (menu items, dialogs, ...) are rendered blank in black (randomly) - check the screenshot below:


    I'm on Ubuntu 16.04.5 with Docker 18.06 and Qt 5.01.

  • Moderators

    But... why? Why docker?

    Anyway. Do other applications show normally? Like some standard Gnome/KDE apps.

    I strongly recommend using something newer than Qt 5.0.1. It was an extremely buggy release. And it's super old.

  • I have the same with Ubuntu 16.04 on Docker and Qt Creator 4.5.2

  • Lifetime Qt Champion

    Nothing we can do about it. Its a docker issue.

    Make sure you run a full Linux with X server etc inside the docker.
    Then i had no issues running my app.

    If you use a special docker, it might have side effects as not operating like a normal OS would.

  • Geeva, was this ever solved?
    I get the same problem with Qt 5.9.5, Ubuntu 18.04.6, GCC 7.5.0, Docker 20.10.14