如何使用另一类中的一个变量？

Question

I understand this question has been asked many times, but I cannot seem to apply it to my code. In my code I have a variable called username in the class Ui_MainWindow, which I want to use in the class.

from viewAllRooms import Ui_ViewAllRooms
from teacher_menu import Ui_Menu
from viewAllRooms import Ui_ViewAllRooms
from PyQt5 import QtCore, QtGui, QtWidgets

class Ui_Menu(QtWidgets.QMainWindow, Ui_Menu):
    def __init__(self, parent=None):
        super(Ui_Menu, self).__init__(parent)
        self.setupUi(self)
        self.viewAll = Ui_ViewAllRooms()
        self.viewall_button.clicked.connect(self.viewAll.show)
        self.viewall_button.clicked.connect(self.hide)

class Ui_ViewAllRooms(QtWidgets.QMainWindow, Ui_ViewAllRooms):
    def __init__(self, parent=None):
        super(Ui_ViewAllRooms, self).__init__(parent)
        self.setupUi(self)
        self.book_Button.clicked.connect(self.book_clicked)

    @QtCore.pyqtSlot()
    def book_clicked(self):
        self._checked_items = []
        self.dialogBook.show()
        self.dialogBook.yes_button.clicked.connect(self.addBooking)

    def addBooking(self):
        now = QDate.currentDate()
        now1 = now.toString(Qt.DefaultLocaleLongDate)
        #I want to use the username here#

class Ui_MainWindow(QtWidgets.QMainWindow, Ui_MainWindow):
    def loginCheck(self):
        username = self.user_enter.text()
        #I have code here which connects to database to check username details
        #If the username is found in database then:
            self.hide()
            self.teacherMenu = Ui_Menu()
            self.teacherMenu.show()

    def __init__(self, parent=None):
        super(Ui_MainWindow, self).__init__(parent)
        self.setupUi(self)
        self.loginCheck()
        self.login_button.clicked.connect(self.loginCheck)

if __name__ == "__main__":
    import sys
    app = QtWidgets.QApplication(sys.argv)
    w = Ui_MainWindow()
    w.show()
    sys.exit(app.exec_())

If you answer, can you please explain how you did it, so I can understand.

Thanks

Answer 1

Code copied from OP but shortened to remove unimportant stuff.

Pass the username variable between the UI instances:

class Ui_Menu(QtWidgets.QMainWindow, Ui_Menu):
    def __init__(self, username, parent=None):
        super(Ui_Menu, self).__init__(parent)
        self.setupUi(self)
        self.viewAll = Ui_ViewAllRooms(username)
        self.viewall_button.clicked.connect(self.viewAll.show)
        self.viewall_button.clicked.connect(self.hide)

class Ui_ViewAllRooms(QtWidgets.QMainWindow, Ui_ViewAllRooms):
    def __init__(self, username, parent=None):
        super(Ui_ViewAllRooms, self).__init__(parent)
        self.username = username
        self.setupUi(self)
        self.book_Button.clicked.connect(self.book_clicked)
        #-----------#

    def addBooking(self):
        now = QDate.currentDate()
        now1 = now.toString(Qt.DefaultLocaleLongDate)
        #Use self.username here#

class Ui_MainWindow(QtWidgets.QMainWindow, Ui_MainWindow):
    def loginCheck(self):
        username = self.user_enter.text()
        #I have code here which connects to database to check username details
        #If the username is found in database then:
            self.hide()
            self.teacherMenu = Ui_Menu(username)
            self.teacherMenu.show()

    def __init__(self, parent=None):
        super(Ui_MainWindow, self).__init__(parent)
        self.setupUi(self)
        self.loginCheck()
        self.login_button.clicked.connect(self.loginCheck)

if __name__ == "__main__":
    import sys
    app = QtWidgets.QApplication(sys.argv)
    w = Ui_MainWindow()
    w.show()
    sys.exit(app.exec_())

Search this answer for username to see how it is passed around.

Answer 2

Add this variable to the object attributes by using self :
self.username = self.user_enter.text() . So you can use it in an other method of the class using self.username .