Assigning or changing int property using enum inside QML

[Shardul Vyas]

Consider this simple enum class -

#include <QObject>
class BookTypes : public QObject
{
	Q_GADGET
	Q_ENUMS(AllBooksType)    

public:

	enum AllBooksType{
		eMagazine,
		eReference,
		eTextBook,
		eThesis
	};

signals:

public slots:

};

Type registration in main()

qmlRegisterUncreatableType<BookTypes>("trial", 1, 0, "BookTypes", 
"Don't create qml instance for BookTypes");

And this is sample QML

Rectangle {
		id: rect
		x: 100; y: 100
		width: 100
		height: 70
		color: "PowderBlue"
		border.color: "RoyalBlue"
		border.width: 1
		radius: 3

		MouseArea{
			x: 0; y: 0
			height: parent.height
			width: parent.width
			property int bt: BookTypes.eTextBook //perfect. now bt is 2
			onClicked: {
				console.debug("old book type:- ")
				console.debug(bt) //prints 2
				console.debug("selected book type:- ")
				bt = BookTypes.eReference //gives error - why ?
				console.debug(BookTypes.eReference) //prints 'undefined'
				console.debug(bt)
			}
		}
	}

This means - The enum is properly exposed, since it initializes bt successfully in -

property int bt: BookTypes.eTextBook

What i don't understand is - Why it is not accessible when i try to replace value of bt in handler.

bt = BookTypes.eReference //gives error - why ?

How do i pass such an enum as an argument of Q_INVOKABLE method ? Like:

console.debug(BookTypes.eReference) //prints 'undefined'
SomeObj.someCPPMethod(BookTypes.eReference) // sends 'undefined' and defaults to 0

[Shardul Vyas]

Received answer on Stack Overflow.
Note: The names of enum values must begin with a capital letter in order to be accessible from QML.