Changing QPalette of widget inside QGraphicsScene not working

[vinci]

Hello

I'm trying to change the color of a widget which inherits from QFrame using QPalette. This widget is then used in a QGraphicsScene.

class State : public QFrame {
public:
  State(QString name, QWidget* parent = nullptr) : QFrame{parent} {
    QVBoxLayout* layout{new QVBoxLayout};
    label_->setText(name);
    layout->addWidget(label_);
    setLayout(layout);
    setFrameStyle(QFrame::Box);

    // Not working at all
    QPalette palette{QFrame::palette()};
    palette.setColor(QPalette::Base, Qt::red);
    setPalette(palette);
  }

private:
  QLabel* label_{new QLabel};
};

Sadly this doesn't seem to do anything? I've tried changing various ColorRoles (e.g. Window) but the widget still looks the same. I'm currently using Qt 6.3.0.

[vinci]

I just realized that it actually does work, but only if I disable my stylesheet.
Is this behavior wanted? Does a stylesheet take precedence over locally set palettes?

[JonB]

@vinci said in Changing QPalette of widget inside QGraphicsScene not working:

Does a stylesheet take precedence over locally set palettes?

Yep.

[vinci]

Oh I see thank you.

What's the recommended best practice to "slightly" change a widgets style (e.g. border color) then in case I can't change the applied stylesheet? I really only need some kind of visual cue for two different kind of states.

[SimonSchroeder]

@vinci QPalette is really unreliable. Some colors cannot be changed by the QPalette and it depends on the style which palette colors influence which part of the widgets. So, I advocate to try to not use QPalette at all.

The best way is actually using stylesheets. You can just set a stylesheet on just this one QFrame object. It can be a small stylesheet changing only this one little thing. Everything else will be inherited from your current global stylesheet.

[vinci]

Alright, I'll look into that.
Thanks for the fast answers!

[SGaist]

Hi,

I would recommend a look at this excellent article from KDAB about using custom QStyle.