Python 从创建UI的单独文件（类）中设置初始组合框值

我花了很多时间使用tkinter制作GUI，但从未使用过OOP风格，所以我想开始学习PyQt5，然后开始学习OOP（当然要努力学习）

我目前有三个文件：

app.py应用程序的“主要入口点”

main_menu.py-从PyQt designer.ui文件转换而来的Python文件

add_functions.py-该文件将具有基于用户操作更新GUI的函数，并通过单击按钮运行函数

我的问题是，如何在创建小部件的“main_menu.py”文件之外更新组合框的初始值？我假设我在“app.py”文件中的某个地方这样做，但我无法理解

下面的代码不会抛出任何错误，但组合框为空，其中一个应为字符串列表，另一个应为单个字符串（稍后将根据第一个组合框选择进行更新）

我基本上可以让它处理“main_menu.py”文件中的所有内容，但后来我意识到每次我想更改UI时，都会产生问题

app.py

from PyQt5.QtWidgets import QMainWindow
from PyQt5 import QtWidgets

# import GUI from designer file
from main_menu import Ui_main_menu
# import other functions
from add_functions import ChangeLists


class Main(QMainWindow, Ui_main_menu):
    def __init__(self, parent=None):
        super(Main, self).__init__(parent)
        self.setupUi(self)

        # Team List
        team_list_file = open(r'C:\NHLdb_pyqt\files\NHLteams.txt', 'r')
        team_list = team_list_file.read().splitlines()
        team_list_file.close()
        print("team list: ", team_list)
        # Initial Player List
        player_list_init = "Please Select a Team"
        # update combo box lists
        print("team list: ", team_list)
        self.team_select_combobox.addItems(team_list)
        self.player_select_combobox.addItem(player_list_init)
        # connect combo box to function that will change player list based on team list selection
        # self.team_select_combobox.currentTextChanged.connect(ChangeLists.team_changed)


if __name__ == "__main__":
    import sys

    app = QtWidgets.QApplication(sys.argv)
    main_menu = QtWidgets.QDialog()
    ui = Ui_main_menu()
    ui.setupUi(main_menu)
    main_menu.show()
    sys.exit(app.exec_())

from PyQt5 import QtCore, QtGui, QtWidgets


class Ui_main_menu(object):
    def setupUi(self, main_menu):
        main_menu.setObjectName("main_menu")
        main_menu.resize(463, 408)
        self.horizontalLayout_2 = QtWidgets.QHBoxLayout(main_menu)
        self.horizontalLayout_2.setObjectName("horizontalLayout_2")
        self.tabWidget = QtWidgets.QTabWidget(main_menu)
        self.tabWidget.setObjectName("tabWidget")
        self.get_data_tab = QtWidgets.QWidget()
        self.get_data_tab.setObjectName("get_data_tab")
        self.verticalLayout = QtWidgets.QVBoxLayout(self.get_data_tab)
        self.verticalLayout.setObjectName("verticalLayout")
        self.team_player_layout = QtWidgets.QGridLayout()
        self.team_player_layout.setObjectName("team_player_layout")
        self.player_select_label = QtWidgets.QLabel(self.get_data_tab)
        self.player_select_label.setAlignment(QtCore.Qt.AlignCenter)
        self.player_select_label.setObjectName("player_select_label")
        self.team_player_layout.addWidget(self.player_select_label, 2, 0, 1, 1)
        self.team_select_combobox = QtWidgets.QComboBox(self.get_data_tab)
        self.team_select_combobox.setCurrentText("")
        self.team_select_combobox.setPlaceholderText("")
        self.team_select_combobox.setObjectName("team_select_combobox")
        self.team_player_layout.addWidget(self.team_select_combobox, 0, 1, 1, 1)
        self.player_select_combobox = QtWidgets.QComboBox(self.get_data_tab)
        self.player_select_combobox.setObjectName("player_select_combobox")
        self.team_player_layout.addWidget(self.player_select_combobox, 2, 1, 1, 1)
        self.team_select_label = QtWidgets.QLabel(self.get_data_tab)
        self.team_select_label.setAlignment(QtCore.Qt.AlignCenter)
        self.team_select_label.setObjectName("team_select_label")
        self.team_player_layout.addWidget(self.team_select_label, 0, 0, 1, 1)
        self.get_player_data_button = QtWidgets.QPushButton(self.get_data_tab)
        self.get_player_data_button.setObjectName("get_player_data_button")
        self.team_player_layout.addWidget(self.get_player_data_button, 3, 0, 1, 2)
        self.verticalLayout.addLayout(self.team_player_layout)
        self.tableWidget = QtWidgets.QTableWidget(self.get_data_tab)
        sizePolicy = QtWidgets.QSizePolicy(QtWidgets.QSizePolicy.Expanding, QtWidgets.QSizePolicy.Expanding)
        sizePolicy.setHorizontalStretch(0)
        sizePolicy.setVerticalStretch(0)
        sizePolicy.setHeightForWidth(self.tableWidget.sizePolicy().hasHeightForWidth())
        self.tableWidget.setSizePolicy(sizePolicy)
        self.tableWidget.setObjectName("tableWidget")
        self.tableWidget.setColumnCount(4)
        self.tableWidget.setRowCount(0)
        item = QtWidgets.QTableWidgetItem()
        self.tableWidget.setHorizontalHeaderItem(0, item)
        item = QtWidgets.QTableWidgetItem()
        self.tableWidget.setHorizontalHeaderItem(1, item)
        item = QtWidgets.QTableWidgetItem()
        self.tableWidget.setHorizontalHeaderItem(2, item)
        item = QtWidgets.QTableWidgetItem()
        self.tableWidget.setHorizontalHeaderItem(3, item)
        self.verticalLayout.addWidget(self.tableWidget)
        self.tabWidget.addTab(self.get_data_tab, "")
        self.view_db_tab = QtWidgets.QWidget()
        self.view_db_tab.setObjectName("view_db_tab")
        self.tabWidget.addTab(self.view_db_tab, "")
        self.horizontalLayout_2.addWidget(self.tabWidget)

        self.retranslateUi(main_menu)
        self.tabWidget.setCurrentIndex(0)
        QtCore.QMetaObject.connectSlotsByName(main_menu)

    def retranslateUi(self, main_menu):
        _translate = QtCore.QCoreApplication.translate
        main_menu.setWindowTitle(_translate("main_menu", "NHL Database"))
        self.player_select_label.setText(_translate("main_menu", "Select A Player:"))
        self.team_select_label.setText(_translate("main_menu", "Select A Team:"))
        self.get_player_data_button.setText(_translate("main_menu", "Get Player Data"))
        item = self.tableWidget.horizontalHeaderItem(0)
        item.setText(_translate("main_menu", "Year"))
        item = self.tableWidget.horizontalHeaderItem(1)
        item.setText(_translate("main_menu", "Team"))
        item = self.tableWidget.horizontalHeaderItem(2)
        item.setText(_translate("main_menu", "League"))
        item = self.tableWidget.horizontalHeaderItem(3)
        item.setText(_translate("main_menu", "GP"))
        self.tabWidget.setTabText(self.tabWidget.indexOf(self.get_data_tab), _translate("main_menu", "Get Player Data"))
        self.tabWidget.setTabText(self.tabWidget.indexOf(self.view_db_tab), _translate("main_menu", "View Database"))

from PyQt5 import QtWidgets
from main_menu import Ui_main_menu


class Main(QtWidgets.QDialog, Ui_main_menu):
    def __init__(self):
        super().__init__()
        # setup ui
        self.setupUi(self)

        # Team List
        team_list_file = open(r'D:\temp.txt', 'r')
        team_list = team_list_file.read().splitlines()
        team_list_file.close()
        # Initial Player List
        player_list_init = "Please Select a Team"
        # update combo box lists
        self.team_select_combobox.addItems(team_list)
        self.player_select_combobox.addItem(player_list_init)


if __name__ == "__main__":
    app = QtWidgets.QApplication([])
    ui = Main()
    ui.show()
    app.exec_()

主菜单.py

from PyQt5.QtWidgets import QMainWindow
from PyQt5 import QtWidgets

# import GUI from designer file
from main_menu import Ui_main_menu
# import other functions
from add_functions import ChangeLists


class Main(QMainWindow, Ui_main_menu):
    def __init__(self, parent=None):
        super(Main, self).__init__(parent)
        self.setupUi(self)

        # Team List
        team_list_file = open(r'C:\NHLdb_pyqt\files\NHLteams.txt', 'r')
        team_list = team_list_file.read().splitlines()
        team_list_file.close()
        print("team list: ", team_list)
        # Initial Player List
        player_list_init = "Please Select a Team"
        # update combo box lists
        print("team list: ", team_list)
        self.team_select_combobox.addItems(team_list)
        self.player_select_combobox.addItem(player_list_init)
        # connect combo box to function that will change player list based on team list selection
        # self.team_select_combobox.currentTextChanged.connect(ChangeLists.team_changed)


if __name__ == "__main__":
    import sys

    app = QtWidgets.QApplication(sys.argv)
    main_menu = QtWidgets.QDialog()
    ui = Ui_main_menu()
    ui.setupUi(main_menu)
    main_menu.show()
    sys.exit(app.exec_())

from PyQt5 import QtCore, QtGui, QtWidgets


class Ui_main_menu(object):
    def setupUi(self, main_menu):
        main_menu.setObjectName("main_menu")
        main_menu.resize(463, 408)
        self.horizontalLayout_2 = QtWidgets.QHBoxLayout(main_menu)
        self.horizontalLayout_2.setObjectName("horizontalLayout_2")
        self.tabWidget = QtWidgets.QTabWidget(main_menu)
        self.tabWidget.setObjectName("tabWidget")
        self.get_data_tab = QtWidgets.QWidget()
        self.get_data_tab.setObjectName("get_data_tab")
        self.verticalLayout = QtWidgets.QVBoxLayout(self.get_data_tab)
        self.verticalLayout.setObjectName("verticalLayout")
        self.team_player_layout = QtWidgets.QGridLayout()
        self.team_player_layout.setObjectName("team_player_layout")
        self.player_select_label = QtWidgets.QLabel(self.get_data_tab)
        self.player_select_label.setAlignment(QtCore.Qt.AlignCenter)
        self.player_select_label.setObjectName("player_select_label")
        self.team_player_layout.addWidget(self.player_select_label, 2, 0, 1, 1)
        self.team_select_combobox = QtWidgets.QComboBox(self.get_data_tab)
        self.team_select_combobox.setCurrentText("")
        self.team_select_combobox.setPlaceholderText("")
        self.team_select_combobox.setObjectName("team_select_combobox")
        self.team_player_layout.addWidget(self.team_select_combobox, 0, 1, 1, 1)
        self.player_select_combobox = QtWidgets.QComboBox(self.get_data_tab)
        self.player_select_combobox.setObjectName("player_select_combobox")
        self.team_player_layout.addWidget(self.player_select_combobox, 2, 1, 1, 1)
        self.team_select_label = QtWidgets.QLabel(self.get_data_tab)
        self.team_select_label.setAlignment(QtCore.Qt.AlignCenter)
        self.team_select_label.setObjectName("team_select_label")
        self.team_player_layout.addWidget(self.team_select_label, 0, 0, 1, 1)
        self.get_player_data_button = QtWidgets.QPushButton(self.get_data_tab)
        self.get_player_data_button.setObjectName("get_player_data_button")
        self.team_player_layout.addWidget(self.get_player_data_button, 3, 0, 1, 2)
        self.verticalLayout.addLayout(self.team_player_layout)
        self.tableWidget = QtWidgets.QTableWidget(self.get_data_tab)
        sizePolicy = QtWidgets.QSizePolicy(QtWidgets.QSizePolicy.Expanding, QtWidgets.QSizePolicy.Expanding)
        sizePolicy.setHorizontalStretch(0)
        sizePolicy.setVerticalStretch(0)
        sizePolicy.setHeightForWidth(self.tableWidget.sizePolicy().hasHeightForWidth())
        self.tableWidget.setSizePolicy(sizePolicy)
        self.tableWidget.setObjectName("tableWidget")
        self.tableWidget.setColumnCount(4)
        self.tableWidget.setRowCount(0)
        item = QtWidgets.QTableWidgetItem()
        self.tableWidget.setHorizontalHeaderItem(0, item)
        item = QtWidgets.QTableWidgetItem()
        self.tableWidget.setHorizontalHeaderItem(1, item)
        item = QtWidgets.QTableWidgetItem()
        self.tableWidget.setHorizontalHeaderItem(2, item)
        item = QtWidgets.QTableWidgetItem()
        self.tableWidget.setHorizontalHeaderItem(3, item)
        self.verticalLayout.addWidget(self.tableWidget)
        self.tabWidget.addTab(self.get_data_tab, "")
        self.view_db_tab = QtWidgets.QWidget()
        self.view_db_tab.setObjectName("view_db_tab")
        self.tabWidget.addTab(self.view_db_tab, "")
        self.horizontalLayout_2.addWidget(self.tabWidget)

        self.retranslateUi(main_menu)
        self.tabWidget.setCurrentIndex(0)
        QtCore.QMetaObject.connectSlotsByName(main_menu)

    def retranslateUi(self, main_menu):
        _translate = QtCore.QCoreApplication.translate
        main_menu.setWindowTitle(_translate("main_menu", "NHL Database"))
        self.player_select_label.setText(_translate("main_menu", "Select A Player:"))
        self.team_select_label.setText(_translate("main_menu", "Select A Team:"))
        self.get_player_data_button.setText(_translate("main_menu", "Get Player Data"))
        item = self.tableWidget.horizontalHeaderItem(0)
        item.setText(_translate("main_menu", "Year"))
        item = self.tableWidget.horizontalHeaderItem(1)
        item.setText(_translate("main_menu", "Team"))
        item = self.tableWidget.horizontalHeaderItem(2)
        item.setText(_translate("main_menu", "League"))
        item = self.tableWidget.horizontalHeaderItem(3)
        item.setText(_translate("main_menu", "GP"))
        self.tabWidget.setTabText(self.tabWidget.indexOf(self.get_data_tab), _translate("main_menu", "Get Player Data"))
        self.tabWidget.setTabText(self.tabWidget.indexOf(self.view_db_tab), _translate("main_menu", "View Database"))

from PyQt5 import QtWidgets
from main_menu import Ui_main_menu


class Main(QtWidgets.QDialog, Ui_main_menu):
    def __init__(self):
        super().__init__()
        # setup ui
        self.setupUi(self)

        # Team List
        team_list_file = open(r'D:\temp.txt', 'r')
        team_list = team_list_file.read().splitlines()
        team_list_file.close()
        # Initial Player List
        player_list_init = "Please Select a Team"
        # update combo box lists
        self.team_select_combobox.addItems(team_list)
        self.player_select_combobox.addItem(player_list_init)


if __name__ == "__main__":
    app = QtWidgets.QApplication([])
    ui = Main()
    ui.show()
    app.exec_()

添加函数

from os import path
from PyQt5 import QtCore, QtGui, QtWidgets


class ChangeLists:
    def team_changed(self):
        index = self.team_select_combobox.currentText()
        if index != 0 and path.exists(r'C:\NHLdb\files\_' + str(index) + '.txt'):
            player_list_file = open(r'C:\NHLdb\files\_' + str(index) + '.txt', 'r')
            player_list_update = player_list_file.read().splitlines()
            player_list_file.close()
            self.player_select_combobox.clear()
            self.player_select_combobox.addItems(player_list_update)
        if index != 0 and not path.exists(r'C:\NHLdb\files\_' + str(index) + '.txt'):
            self.player_select_combobox.clear()
            self.player_select_combobox.addItem("Prospects Not Compiled")

---

你在app.py中的呼叫顺序有点不正确。类Main永远不会被调用，因此在那里定义的初始化例程永远不会被执行。此外，类Main继承自错误的窗口类型。在您的例子中，您设计了一个QDialog，因此它应该继承它（而不是QMainWindow）

解决这些问题后，您在Main类中定义的所有内容都应按预期工作：

修改的app.py

from PyQt5.QtWidgets import QMainWindow
from PyQt5 import QtWidgets

# import GUI from designer file
from main_menu import Ui_main_menu
# import other functions
from add_functions import ChangeLists


class Main(QMainWindow, Ui_main_menu):
    def __init__(self, parent=None):
        super(Main, self).__init__(parent)
        self.setupUi(self)

        # Team List
        team_list_file = open(r'C:\NHLdb_pyqt\files\NHLteams.txt', 'r')
        team_list = team_list_file.read().splitlines()
        team_list_file.close()
        print("team list: ", team_list)
        # Initial Player List
        player_list_init = "Please Select a Team"
        # update combo box lists
        print("team list: ", team_list)
        self.team_select_combobox.addItems(team_list)
        self.player_select_combobox.addItem(player_list_init)
        # connect combo box to function that will change player list based on team list selection
        # self.team_select_combobox.currentTextChanged.connect(ChangeLists.team_changed)


if __name__ == "__main__":
    import sys

    app = QtWidgets.QApplication(sys.argv)
    main_menu = QtWidgets.QDialog()
    ui = Ui_main_menu()
    ui.setupUi(main_menu)
    main_menu.show()
    sys.exit(app.exec_())

from PyQt5 import QtCore, QtGui, QtWidgets


class Ui_main_menu(object):
    def setupUi(self, main_menu):
        main_menu.setObjectName("main_menu")
        main_menu.resize(463, 408)
        self.horizontalLayout_2 = QtWidgets.QHBoxLayout(main_menu)
        self.horizontalLayout_2.setObjectName("horizontalLayout_2")
        self.tabWidget = QtWidgets.QTabWidget(main_menu)
        self.tabWidget.setObjectName("tabWidget")
        self.get_data_tab = QtWidgets.QWidget()
        self.get_data_tab.setObjectName("get_data_tab")
        self.verticalLayout = QtWidgets.QVBoxLayout(self.get_data_tab)
        self.verticalLayout.setObjectName("verticalLayout")
        self.team_player_layout = QtWidgets.QGridLayout()
        self.team_player_layout.setObjectName("team_player_layout")
        self.player_select_label = QtWidgets.QLabel(self.get_data_tab)
        self.player_select_label.setAlignment(QtCore.Qt.AlignCenter)
        self.player_select_label.setObjectName("player_select_label")
        self.team_player_layout.addWidget(self.player_select_label, 2, 0, 1, 1)
        self.team_select_combobox = QtWidgets.QComboBox(self.get_data_tab)
        self.team_select_combobox.setCurrentText("")
        self.team_select_combobox.setPlaceholderText("")
        self.team_select_combobox.setObjectName("team_select_combobox")
        self.team_player_layout.addWidget(self.team_select_combobox, 0, 1, 1, 1)
        self.player_select_combobox = QtWidgets.QComboBox(self.get_data_tab)
        self.player_select_combobox.setObjectName("player_select_combobox")
        self.team_player_layout.addWidget(self.player_select_combobox, 2, 1, 1, 1)
        self.team_select_label = QtWidgets.QLabel(self.get_data_tab)
        self.team_select_label.setAlignment(QtCore.Qt.AlignCenter)
        self.team_select_label.setObjectName("team_select_label")
        self.team_player_layout.addWidget(self.team_select_label, 0, 0, 1, 1)
        self.get_player_data_button = QtWidgets.QPushButton(self.get_data_tab)
        self.get_player_data_button.setObjectName("get_player_data_button")
        self.team_player_layout.addWidget(self.get_player_data_button, 3, 0, 1, 2)
        self.verticalLayout.addLayout(self.team_player_layout)
        self.tableWidget = QtWidgets.QTableWidget(self.get_data_tab)
        sizePolicy = QtWidgets.QSizePolicy(QtWidgets.QSizePolicy.Expanding, QtWidgets.QSizePolicy.Expanding)
        sizePolicy.setHorizontalStretch(0)
        sizePolicy.setVerticalStretch(0)
        sizePolicy.setHeightForWidth(self.tableWidget.sizePolicy().hasHeightForWidth())
        self.tableWidget.setSizePolicy(sizePolicy)
        self.tableWidget.setObjectName("tableWidget")
        self.tableWidget.setColumnCount(4)
        self.tableWidget.setRowCount(0)
        item = QtWidgets.QTableWidgetItem()
        self.tableWidget.setHorizontalHeaderItem(0, item)
        item = QtWidgets.QTableWidgetItem()
        self.tableWidget.setHorizontalHeaderItem(1, item)
        item = QtWidgets.QTableWidgetItem()
        self.tableWidget.setHorizontalHeaderItem(2, item)
        item = QtWidgets.QTableWidgetItem()
        self.tableWidget.setHorizontalHeaderItem(3, item)
        self.verticalLayout.addWidget(self.tableWidget)
        self.tabWidget.addTab(self.get_data_tab, "")
        self.view_db_tab = QtWidgets.QWidget()
        self.view_db_tab.setObjectName("view_db_tab")
        self.tabWidget.addTab(self.view_db_tab, "")
        self.horizontalLayout_2.addWidget(self.tabWidget)

        self.retranslateUi(main_menu)
        self.tabWidget.setCurrentIndex(0)
        QtCore.QMetaObject.connectSlotsByName(main_menu)

    def retranslateUi(self, main_menu):
        _translate = QtCore.QCoreApplication.translate
        main_menu.setWindowTitle(_translate("main_menu", "NHL Database"))
        self.player_select_label.setText(_translate("main_menu", "Select A Player:"))
        self.team_select_label.setText(_translate("main_menu", "Select A Team:"))
        self.get_player_data_button.setText(_translate("main_menu", "Get Player Data"))
        item = self.tableWidget.horizontalHeaderItem(0)
        item.setText(_translate("main_menu", "Year"))
        item = self.tableWidget.horizontalHeaderItem(1)
        item.setText(_translate("main_menu", "Team"))
        item = self.tableWidget.horizontalHeaderItem(2)
        item.setText(_translate("main_menu", "League"))
        item = self.tableWidget.horizontalHeaderItem(3)
        item.setText(_translate("main_menu", "GP"))
        self.tabWidget.setTabText(self.tabWidget.indexOf(self.get_data_tab), _translate("main_menu", "Get Player Data"))
        self.tabWidget.setTabText(self.tabWidget.indexOf(self.view_db_tab), _translate("main_menu", "View Database"))

from PyQt5 import QtWidgets
from main_menu import Ui_main_menu


class Main(QtWidgets.QDialog, Ui_main_menu):
    def __init__(self):
        super().__init__()
        # setup ui
        self.setupUi(self)

        # Team List
        team_list_file = open(r'D:\temp.txt', 'r')
        team_list = team_list_file.read().splitlines()
        team_list_file.close()
        # Initial Player List
        player_list_init = "Please Select a Team"
        # update combo box lists
        self.team_select_combobox.addItems(team_list)
        self.player_select_combobox.addItem(player_list_init)


if __name__ == "__main__":
    app = QtWidgets.QApplication([])
    ui = Main()
    ui.show()
    app.exec_()