Colour differences in a group box on Windows

[Perdrix]

I set the background colour of some group boxes to "light cyan" or "dark cyan" depending on the active Windows theme (light/dark).

However the colour displayed varies:

Which doesn't seem quite right ...

Am I doing something wrong or is it Qt (6.5.1).

[Christian Ehrlicher]

'Settings...' is a QLabel, not a QGroupBox.

[Perdrix]

@Christian-Ehrlicher And it should inherit the background colour from the Groupbox (shouldn't it)?

[Christian Ehrlicher]

@Perdrix said in Colour differences in a group box on Windows:

And it should inherit the background colour from the Groupbox (shouldn't it)?

I don't know - you did not show any code on what you're doing.

[Perdrix]

@Christian-Ehrlicher Sorry here's my code that sets the colour for the group box:

ui->options->setStyleSheet(QString("background-color: %1").arg(activeGroupColourName));

the variable activeGroupColourName will be either "light-cyan" or "dark-cyan" depending on the active Windows theme.

AFAIK the style background colour should propagate down from the group box to the contained QLabels?

D.

[Perdrix]

Has anyone got some thoughts on this issue?

Thanks, D.

[Christian Ehrlicher]

You should be long enough here to know that we need a minimal, compilable example to reproduce the problem.
Works fine for me on windows with Qt6.7:

int main(int argc, char* argv[])
{
    QApplication app(argc, argv);
    QWidget w;
    w.setStyleSheet("background-color: red");
    QHBoxLayout* lay = new QHBoxLayout(&w);
    QGroupBox* groupBox = new QGroupBox("GroupBox");
    QVBoxLayout* vbox = new QVBoxLayout(groupBox);
    vbox->addWidget(new QLabel("Label 1"));
    vbox->addWidget(new QLabel("Label 2"));
    vbox->addWidget(new QLabel("Label 3"));
    lay->addWidget(groupBox);
    w.show();
    return app.exec();
}

[Perdrix]

@Christian-Ehrlicher Yes, but if I knew how to create the problem, I'd probably know how to fix it!!! In this case I haven't a clue why it is happening.

[Christian Ehrlicher]

You wanted an answer if you're doing something wrong or if it's a Qt bug. As long as you can't prove that there is a Qt bug (= you can provide a small testcase to reproduce the problem) the answer is - you're doing something wrong. Don't know how we could help here further.

[Perdrix]

@Christian-Ehrlicher Err no, it could still be a Qt problem that I can't work out how to create a small test case for...