创建自定义类 QPointF

Question

我想用计算欧几里得距离的方法创建我的类 Point。Point 类继承自 QPointF 类。但是在执行 add 或 mul 等操作时，结果不是 Point 类，而是 QPointF。如何解决？我应该覆盖所有魔术方法还是有其他解决方案？from PyQt5.QtCore import QPointFclass Point(QPointF):    def __init__(self, *args, **kwargs):        super(QPointF, self).__init__(*args, **kwargs)    def dist(self):        return (self._p.x() * self._p.x() +                self._p.y() * self._p.y()) ** 0.5 a = Point(1, 2) b = Point(2, 3) print(a + b, type(a + b))>> PyQt5.QtCore.QPointF(3.0, 5.0) <class 'PyQt5.QtCore.QPointF'>

Answer 1

是的，您必须覆盖方法__add__，__mul__并且__repr__：

from PyQt5.QtCore import QPointF

class Point(QPointF):

    def dist(self):

        return (self._p.x() * self._p.x() + self._p.y() * self._p.y()) ** 0.5

    def __add__(self, other):

        return self.__class__(super(self.__class__, self).__add__(other))

    def __mul__(self, other):

        return self.__class__(super(self.__class__, self).__mul__(other))

    def __repr__(self):

        return "{}({}, {})".format(self.__class__.__name__, self.x(), self.y())

if __name__ == '__main__':

    a = Point(1, 2)

    b = Point(2, 3)

    print(a, type(a))

    print(b, type(b))

    print(a + b, type(a + b))

    a += Point(10, 10)

    print(a, type(a))

    a += QPointF(10, 10)

    print(a, type(a))

    print(a*3, type(a*3))

    print("a: {}".format(a))

    l = [a, b]

    print(l)