qproperty.py

from PyQt5.QtCore import QObject, pyqtProperty


class Q_Property(pyqtProperty):
    """
    A descriptor that more closely resembles the Q_PROPERTY macro.

    Encourage a coding style which is consistent with Qt.

    Example:
    >>> class Foo(QObject):
    ...     _bar = 0
    ...     def bar(self):
    ...         return self._bar
    ...     def setBar(self, bar):
    ...         self._bar = bar
    ...     bar = Q_Property(int, fget=bar, fset=setBar)

    >>> obj = Foo()
    >>> obj.setBar(2)
    >>> obj.bar()
    2
    >>> obj.setProperty("bar", 42)
    True
    >>> obj.property("bar")
    42
    >>> obj.bar()
    42
    """
    def __get__(self, obj, cls=None):
        # Simply return the contained (bound) fget method
        return self.fget.__get__(obj, cls)

    def __set__(self, obj, value):
        raise TypeError

    # these cannot work with this style of use
    def setter(self, f):
        raise RuntimeError

    def getter(self, f):
        raise RuntimeError