将PyQT5信号从服务类别连接到多个插槽

时间:2018-11-17 17:11:39

标签: python pyqt5 signals-slots

我构建了一个(单例)服务类,其中包括“ something_changed”信号。该服务包含在基本父类中,并在其中连接到插槽。从该父类中,派生了两个子类Child1和Child2,它们都在main方法中初始化。

当我发送信号时,似乎仅执行了最后一个连接的子级的插槽(似乎与文档和其他来源,例如here相比)只有一个连接是可能的。

为演示我的问题,我简化了类:

Service.py

from PyQt5.QtCore import QObject, pyqtSignal

class Service(QObject):
    __instance = None

    something_changed = pyqtSignal()

    def __new__(cls) -> "Service":
        if cls.__instance is None:
            print("Creating new service instance")
            cls.__instance = QObject.__new__(cls)
        else:
            print("Returning existing service instance")

        return cls.__instance

    def do_something(self):
        print("Do something")
        self.something_changed.emit()

Classes.py

from PyQt5.QtCore import QObject
from Service import Service

class Parent(QObject):
    def __init__(self):
        super().__init__()
        self._service = Service()
        self._service.something_changed.connect(self._something_changed)
        print("Init Parent: " + self.__class__.__name__)

    def _something_changed(self):
        print("Parent - _something_changed: " + self.__class__.__name__)


class Child1(Parent):
    def __init__(self):
        super().__init__()
        print("Init Child1: " + self.__class__.__name__)

    def _something_changed(self):
        print("Child1 - _something_changed: " + self.__class__.__name__)


class Child2(Parent):
    def __init__(self):
        super().__init__()
        print("Init Child2: " + self.__class__.__name__)

    def _something_changed(self):
        print("Child2 - _something_changed: " + self.__class__.__name__)

main.py

from Classes import Child1, Child2
from Service import Service

if __name__ == "__main__":
    service = Service()

    child1 = Child1()
    child2 = Child2()

    service.do_something()

以及结果输出:

Creating new service instance
Returning existing service instance
Init Parent: Child1
Init Child1: Child1
Returning existing service instance
Init Parent: Child2
Init Child2: Child2
Do something
Child2 - _something_changed: Child2

我期望并且也试图实现的目标是在信号发出时从两个孩子运行“ _something_changed”功能。

其他节点:

当我评论child2 = Child2()初始化时,将调用child1的“ _something_changed”功能,因此必须建立连接。

谢谢

0 个答案:

没有答案