4. Qt/Android: Use QPainter in secondary thread.

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Qt/Android: Use QPainter in secondary thread.


  • Hi,

    I am using Qt5.2.0 for Android. I would like to draw to a QImage in a QThread object's run() method. But every call into QPainter's drawXXX methods will block for a few seconds and the application terminates. The famous last words are:

    F/libc (21070): Fatal signal 4 (SIGILL) at 0xacc04a10 (code=1), thread 21094 (CMapRMAP)
    D/dalvikvm(21070): GC_FOR_ALLOC freed 111K, 10% free 3092K/3404K, paused 102ms, total 104ms
    F/libc (21070): Fatal signal 11 (SIGSEGV) at 0xacc04a10 (code=2), thread 21094 (CMapRMAP)

    The same code works perfectly on a PC/Linux system. Is this a known issue for Qt/Android? Or does it take some prerequisites to use QPainter in a thread? I am very well aware of the general problem not to use QPixmap as drawing context in a thread. That's why I use QImage.

    Thanks for help.

    Oliver

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  • There should be no platform specific limitation for painting into a QImage on another thread. Best would be to create a bug report on https://bugreports.qt-project.org

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