Scoped enums, Meta Object and Stylesheets

NicolasS

Dear all,

How can I register a scoped enum to the meta-object system ?
I'd like be able to change the value of a scoped enum property via stylesheet but i'm not able to make my code work:

class MyClass : public QWidget
{
	Q_OBJECT;
	Q_ENUMS(Priority);

	Q_PROPERTY(Priority ThePriority MEMBER priority);

public:
	enum struct Priority { High, Low, VeryHigh, VeryLow };


	MyClass(QObject *parent = 0) {}

	~MyClass() {}

	void setPriority(Priority ipriority)
	{
		priority = ipriority;
	}

	Priority getPriority() const
	{
		return priority;
	}

private:
	Priority priority { Priority::High };
};

int main(int argc, char *argv[])
{
	QApplication a(argc, argv);
	a.setStyleSheet(QStringLiteral("MyClass { qproperty-ThePriority: VeryLow;}"));
	
	MyClass myClass;
	myClass.ensurePolished();
	
	Q_ASSERT(myClass.getPriority() == MyClass::Priority::VeryLow); // ASSERT! getPriority() == MyClass::Priority::High

	return a.exec();
}

Any idea ?
Regards
Edit: Fix errors in source code sample

SGaist

Hi,

~~AFAIK, you can't set a property through style sheet. You can create a style sheet that reacts on a property change though.~~

[edit: memory was wrong SGaist]

NicolasS

Yes you can: Setting QObject Properties

SGaist

@NicolasS Thanks for the pointer !

NicolasS

This code works well if I use classic enum: enum Priority { High, Low, VeryHigh, VeryLow };

SGaist

Which version of Qt are you using ?

kshegunov

From your link you would need to use: qproperty-priority instead.
If this doesn't work (and it's just a wild guess) but could you register that enum as an alias in the metatype system, e.g. qRegisterMetatype<Priority>("Priority") in your class' constructor.

NicolasS

@SGaist
I'm using Qt 5.9.4 x64

@kshegunov
You are right, there was typo in my sample. I've edited the code from the main post.
I had no success with qRegisterMetatype, the code doesn't compile.
As you suggested, I've tried this:

MyClass(QObject *parent = 0)
{
   qRegisterMetatype<Priority>("Priority")
}

SGaist

Please use enum class.

moc currently doesn't support enum struct, there's a patch in the work though for that.

NicolasS

It works!
Thanks.