Hi,
i'm trying to remove sunken canvas (it looks ugly).
Qt Code: 
  1. ui->qwtPlot->canvas()->setFrameStyle(QFrame::StyledPanel|QFrame::Plain);
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but the result is a transparent border line around canvas (transparent - probably because my "transparent oxygen" widget style):
snapshot4.png
How to remove this border, and get a elegant round border (as in line edit or table widget)?

i tried
Qt Code: 
  1. ui->qwtPlot->layout()->setMargin(0);
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but program crashes on starting ("The program has unexpectedly finished.")

Thanks for any help