Qt 5.11.0 - QApplication: invalid style override passed, ignoring it.

  • Re: [Qt 5.8.0 - QApplication: invalid style override passed](ignoring it.)

    I have the same issue in this unresolved referenced post. I'm on Linux Cinnamon 18.3, running Qt 5.11.0. During debug, I get this:

    QApplication: invalid style override passed, ignoring it.


        qDebug() << QApplication::style()->metaObject()->className();

    I get this:

    ("Windows", "Fusion")

    I have no idea what to do. I think what has me bugged the most is that the Qt devs haven't resolved this issue yet. However, I'm new to Qt and haven't done anything with it yet. So as far as I know, this will be a non-issue with released work.

    If you can help me with this problem, I'd appreciate you.

  • Lifetime Qt Champion


    What do you get if you define the QT_DEBUG_PLUGINS environment variable ?

  • Okay, you busted me. I'm not just new to Qt but also to C++. I don't know how to do what you asked. Now would be a nice time to learn though, if you don't mind. I apologize for my ignorance.

  • Moderators

    on the command line execute

    export QT_DEBUG_PLUGINS=1

    then run your application from this command line and post the output. The idea is that there is an old plugin somewhere around which creates this error.
    Are you passing a command line option to your application? Esp. '-style' - otherwise I don't know how this warning message could occur...

  • @Christian-Ehrlicher said in Qt 5.11.0 - QApplication: invalid style override passed, ignoring it.:

    export QT_DEBUG_PLUGINS=1

    I pass nothing to the compiler. I Ctrl-9 and that's it.

    I hope I did this right. I don'[t think I did though. The output was way too mkuch for here, so I posted it in a code bin.

  • I mean Ctrl-R. Sorry, I just woke up and haven't even fed the cows and chickens yet. I'd like to resolve this issue though. I appreciate you guys' help.

  • Qt Champions 2017

    export QT_DEBUG_PLUGINS=1
    should be typed in a linux shell.
    Then in same shell you start creator.
    The output suggest you did it right :)

  • I typed export QT_DEBUG_PLUGINS=1 to the Project Folder in my Linux terminal. Then made sure Qt Creator was set to Debug mode. But every time I type in the Debugger Console export QT_DEBUG_PLUGINS=1, it gives me Can only evaluate during a debug session.

  • Qt Champions 2017

    @landslyde said in Qt 5.11.0 - QApplication: invalid style override passed, ignoring it.:

    Can only evaluate during a debug session.

    Its only ment to be set as a environment in a normal linux shell and then Creator started from same shell
    to make it dump info for SO plugins it loads.
    Not sure Debugger Console will understand it as its not debug statement, just a normal environment key.

  • Finally got it. Here's the output.

  • It appears this is a well-known issue, one that, for the life of me, I can't tell if the Qt devs are working on or not. I love the Qt look and feel, its ease of use. But if they can't solve this, or a community fix come to light, then it looks like Qt's dead in the water for me. Hard to believe an app as robust as Qt falls short like this.

  • Qt Champions 2017

    i also get this warning on Mint linux with XFCE.
    It seems related to Cinnamon and gtk(3) stuff.
    Running same setup with KDE did not produce any such warning.
    It has no ill affect on the app running but it might not look native.


  • There's always a "catch", huh? Oh well =)

    Thanks for sharing.

Log in to reply

Looks like your connection to Qt Forum was lost, please wait while we try to reconnect.