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qtqtstylesheetsqdockwidget

QDockWidget change background color when floating

I have a QDockWidget with a transparent background, but I would like to change the background color or background image when it is floating. It doesn't look like the qt style sheets have a pseudo state to tell you whether or not they are floating, so I'd like to know: is this possible to do?

Solution

  • Found the solution. Add the following connection in the code:

        connect(knobDock, &QDockWidget::topLevelChanged, [&] (bool isFloating)
    {
        if (isFloating)
        {
            setAttribute(Qt::WA_TranslucentBackground, false);
            setAttribute(Qt::WA_NoSystemBackground, false); 
        }
    });

    This will cause the dock widgetto use whatever background is specified in the stylesheet when the dock is floating, but it will be transparent (i.e. show the mainwindow background) when it's docked.