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Thread: Transparent Canvas

  1. #1
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    Default Transparent Canvas

    Hi everyone,
    I want to make a semi-transparent canvas for qwtplot.
    But a black background will appear instead of parent widget behind it.
    QwtPlotCanvas Class Reference
    qwtmissed.png

  2. #2
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    Default Re: Transparent Canvas

    Try this in your QwtPlot class

    Qt Code:
    1. QString styleSheet = QString("QwtPlotCanvas { background: rgba(255, 255, 255, 100); }");
    2. setStyleSheet(styleSheet);
    To copy to clipboard, switch view to plain text mode 

  3. #3
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    Default Re: Transparent Canvas

    Better not - style sheets are a nightmare as there is no API to know them. Qwt tries its best to somehow reverse engineer its settings to handle rounded borders etc. but from the point of view of a widget library they are a PITA.
    But for setting the background you can simply change the palette - no need for using style sheets at all.

    Uwe

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