PyQt5:使用 QtDesigner,如何将信号与模块中定义的 slot/callable 连接起来

PyQt5: Using QtDesigner, how do you connect a signal with a slot/callable defined in a module

我是PyQt5的初学者,请原谅我的无知
我正在尝试将按钮与我定义的功能连接

import sys
from PyQt5 import QtGui, QtWidgets,uic


def PrintSomething ():
    print("Hello world")

if __name__ == '__main__':
    app = QtWidgets.QApplication(sys.argv)
    window = uic.loadUi("Auto.ui")
    window.show()
    sys.exit(app.exec_())

为了完成上述操作,我使用 QtDesigner 向 MainWindow 添加了一个插槽 .. 如图所示,然后我将按钮的 Pressed 信号与主窗口的插槽相连 window

当我尝试 运行 应用程序时出现此错误:

AttributeError: 'QMainWindow' 对象没有属性 'PrintSomething'

我哪里做错了?

更新:

这个代码我也用过

import sys
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
from PyQt5.QtCore import *
from Auto import Ui_MainWindow
class MainW (QMainWindow):
    def __init__(self):
        QMainWindow.__init__(self)
        self.ui=Ui_MainWindow()
        self.ui.setupUi(self)
if __name__ == '__main__':
    #topology=topo.LoadTopology()
    app = QApplication(sys.argv)
    myapp = MainW()
    myapp.show()
    sys.exit(app.exec_())

其中 Auto 模块是通过 pyuic5 生成的,并添加了函数 PrintSomething()。这也会导致错误

from PyQt5 import QtCore, QtGui, QtWidgets

class Ui_MainWindow(object):
    def setupUi(self, MainWindow):
        MainWindow.setObjectName("MainWindow")
        MainWindow.resize(667, 487)
        self.centralwidget = QtWidgets.QWidget(MainWindow)
        self.centralwidget.setObjectName("centralwidget")
        self.pushButton = QtWidgets.QPushButton(self.centralwidget)
        self.pushButton.setGeometry(QtCore.QRect(300, 380, 95, 29))
        self.pushButton.setObjectName("pushButton")
        MainWindow.setCentralWidget(self.centralwidget)
        self.menubar = QtWidgets.QMenuBar(MainWindow)
        self.menubar.setGeometry(QtCore.QRect(0, 0, 667, 23))
        self.menubar.setObjectName("menubar")
        self.menuFile = QtWidgets.QMenu(self.menubar)
        self.menuFile.setObjectName("menuFile")
        self.menuExit = QtWidgets.QMenu(self.menubar)
        self.menuExit.setObjectName("menuExit")
        MainWindow.setMenuBar(self.menubar)
        self.statusbar = QtWidgets.QStatusBar(MainWindow)
        self.statusbar.setObjectName("statusbar")
        MainWindow.setStatusBar(self.statusbar)
        self.actionOpen = QtWidgets.QAction(MainWindow)
        self.actionOpen.setObjectName("actionOpen")
        self.actionSave = QtWidgets.QAction(MainWindow)
        self.actionSave.setObjectName("actionSave")
        self.actionClose = QtWidgets.QAction(MainWindow)
        self.actionClose.setObjectName("actionClose")
        self.menuFile.addAction(self.actionOpen)
        self.menuFile.addAction(self.actionSave)
        self.menuFile.addAction(self.actionClose)
        self.menubar.addAction(self.menuFile.menuAction())
        self.menubar.addAction(self.menuExit.menuAction())

        self.retranslateUi(MainWindow)
        self.pushButton.pressed.connect(MainWindow.PrintSomething())
        QtCore.QMetaObject.connectSlotsByName(MainWindow)

    def retranslateUi(self, MainWindow):
        _translate = QtCore.QCoreApplication.translate
        MainWindow.setWindowTitle(_translate("MainWindow", "MainWindow"))
        self.pushButton.setText(_translate("MainWindow", "PushButton"))
        self.menuFile.setTitle(_translate("MainWindow", "File"))
        self.menuExit.setTitle(_translate("MainWindow", "Exit"))
        self.actionOpen.setText(_translate("MainWindow", "Open"))
        self.actionSave.setText(_translate("MainWindow", "Save"))
        self.actionClose.setText(_translate("MainWindow", "Close"))
    def PrintSomething ():
        print("Hello world")

您需要像这样重构您的代码:

import sys
from PyQt5 import QtGui, QtWidgets, uic

class Window(QtWidgets.QMainWindow):
    def __init__(self):
        super(Window, self).__init__()
        uic.loadUi("Auto.ui", self)

    def PrintSomething(self):
        print("Hello world")

if __name__ == '__main__':

    app = QtWidgets.QApplication(sys.argv)
    window = Window()
    window.show()
    sys.exit(app.exec_())

但是,我认为最好在代码中连接信号,而不是通过 Qt Designer 全部完成:

class Window(QtWidgets.QMainWindow):
    def __init__(self):
        ...
        self.pushButton.clicked.connect(self.PrintSomething)

如果您更改了 PrintSomething 插槽的名称,或者想将按钮连接到不同的插槽,则通过 Qt Designer 更改它会很麻烦。在您开发应用程序时,信号连接可能会经常更改,因此手动编码可能更易于管理。

编辑:

添加到问题中的另一个示例可以用类似的方式修复。但是如果你打算使用 pyuic 你应该 永远不要 编辑它生成的模块。相反,你应该像这样简单地将它导入到你的主脚本中:

import sys
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
from PyQt5.QtCore import *
from Auto import Ui_MainWindow

class MainW (QMainWindow, Ui_MainWindow):
    def __init__(self):
        QMainWindow.__init__(self)
        self.setupUi(self)
        self.pushButton.clicked.connect(self.PrintSomething)

    def PrintSomething(self):
        print("Hello world")

if __name__ == '__main__':

    app = QApplication(sys.argv)
    myapp = MainW()
    myapp.show()
    sys.exit(app.exec_())