@QmlElement

This decorator registers a class it is attached to for use in QML, using global variables to specify the import name and version.

QML_IMPORT_NAME = "com.library.name"
QML_IMPORT_MAJOR_VERSION = 1
QML_IMPORT_MINOR_VERSION = 0 # Optional

@QmlElement
class ClassForQml(QObject):
    # ...

Afterwards the class may be used in QML:

import com.library.name 1.0

ClassForQml {
   // ...
}