为什么PYQT5会对我“在0x7f65e800aa60处绑定RowProduct对象的PYQT_SIGNAL mysignal？

Question

我有两个类A和B，从A到B发出信号。当我尝试打印信号对象时，它给了我<bound PYQT_SIGNAL mysignal of RowProduct object at 0x7f65e800aa60>

您能帮我解决为什么会发生这种情况，以及如何将对象读取为有效的python数据类型，以便可以使用所需的方法吗？

import sys
from PyQt5.QtCore import QSize, pyqtSignal
from PyQt5.QtWidgets import *

class A(QWidget):

    my_signal = pyqtSignal(str)

    def __init__(self, parent=None):
        super(A, self).__init__(parent)
        self.gridlay = QGridLayout(self)

        self.btn = QPushButton('10')
        self.btn.setMinimumSize(QSize(150, 150))
        self.btn.clicked.connect(self.send_data)
        self.gridlay.addWidget(self.btn, 0, 0, 1, 1)

        self.btn_1 = QPushButton('20')
        self.btn_1.setMinimumSize(QSize(150, 150))
        self.btn_1.clicked.connect(self.send_data)
        self.gridlay.addWidget(self.btn_1, 0, 1, 1, 1)

        self.btn_2 = QPushButton('30')
        self.btn_2.setMinimumSize(QSize(150, 150))
        self.btn_2.clicked.connect(self.send_data)
        self.gridlay.addWidget(self.btn_2, 1, 0, 1, 2)

    def send_data(self):
        sender = self.sender()
        self.my_signal.emit(sender.text())
        print(self.my_signal)
        self.close()


class B(QWidget):

    product = ''

    def __init__(self, parent=None):
        super(B, self).__init__(parent)
        self.grid = QGridLayout(self)

        self.la = QLabel()
        self.la.setMinimumSize(200, 50)
        self.grid.addWidget(self.la, 0, 0, 1, 1)

        self.btn = QPushButton('click me i am the main window')
        self.btn.setMinimumSize(QSize(200, 150))
        self.btn.clicked.connect(self.fire)
        self.grid.addWidget(self.btn, 1, 0, 1, 1)

        self.con = A()
        self.con.my_signal.connect(self.signal_receiver)

    def fire(self):
        self.con.show()

    def signal_receiver(self, incoming_signal):
        self.product = incoming_signal
        print(self.product)
        self.la.setText(self.product)


if __name__ == '__main__':
    app = QApplication(sys.argv)
    w = B()
    w.show()
    sys.exit(app.exec_())

更新，这是我的代码的最小可复制示例，此代码可以正常工作，而在主代码中，发出的对象未连接到所需的方法。

Answer 1

这是python 3.6的示例。示例使用协程和事件循环创建多个示例。您可以修改signal_slot方法以打印信号对象以重现您的情况

from PyQt5.QtCore import (pyqtSignal, pyqtSlot, QObject)
import asyncio
import datetime

#custom DataModel to pass as signal parameter
class CustomObject:
    _id = None
    _name = None
    _date = None

    def __init__(self, _id, _name, _date):
        self._id = _id
        self._name = _name
        self._date = _date

    @property
    def id(self):
        return self._id

    @property
    def name(self):
        return self._name

    @property
    def date(self):
        return self._date

#classes which leverage signal should be inherited from QObject
class A(QObject):
    signal = pyqtSignal(object)

    def __init__(self):
        try:
            # init line chould have been missed in your case
            QObject.__init__(self)
            print("class A initialized")
        except Exception as e:
            print(e)

    def method_call(self, _custom_object):
        self.signal.emit(_custom_object)

#classes which leverage signal should be inherited from QObject
class B(QObject):
    def __init__(self, _custom_object):
        try:
            # init line chould have been missed in your case
            QObject.__init__(self)
            print("class B initialized")
            a = A()
            # slot method should still work if not decorated with slot
            # its provided here with slot decorator as best practice
            a.signal.connect(self.slot)
            a.method_call(_custom_object)

        except Exception as e:
            print(e)

    @pyqtSlot(object)
    def slot(self, _custom_object):
        if isinstance(_custom_object, CustomObject):
            print(f"id: {_custom_object.id}, name:{_custom_object.name}, date: {_custom_object.date}")

# sample coroutine as infinite reproducible call 
@asyncio.coroutine
async def signal_slot():
    c = 0
    while True:
        c = c + 1
        custom_object = CustomObject(c, f"object {c}", datetime.datetime.now())
        b = B(_custom_object=custom_object)
        await asyncio.sleep(1)


if __name__ == "__main__":
    loop = asyncio.new_event_loop()
    asyncio.set_event_loop(loop)
    loop.run_until_complete(signal_slot())

输出

class B initialized
class A initialized
id: 1, name:object 1, date: 2019-12-29 15:37:15.240500
class B initialized
class A initialized
id: 2, name:object 2, date: 2019-12-29 15:37:16.240738
class B initialized
class A initialized
id: 3, name:object 3, date: 2019-12-29 15:37:17.241039
class B initialized
class A initialized
id: 4, name:object 4, date: 2019-12-29 15:37:18.241728
class B initialized
class A initialized
id: 5, name:object 5, date: 2019-12-29 15:37:19.242258
....
....