如何在Python中的類之間共享變量

Question

我目前正在嘗試創建一個基本的Gmail客戶端，並且試圖在Authen和Application兩個類之間共享我的登錄詳細信息。 我需要訪問在Authen類中輸入的功勞，但是我不太清楚該怎么做。 這是我當前的代碼，在Application類中：

Username_mine = passcheck.Create_Widgets.Username.get()
Password_mine = passcheck.Create_Widgets.Password.get()
contents = self.Body.get("0.0", END)
FROM = "Unknown"
subject = self.Subject_Entry.get()
recipients = self.To_Entry.get()
server = smtplib.SMTP('smtp.gmail.com:587')
server.ehlo()
server.starttls()
server.login(Username_mine, Password_mine)
server.sendmail(FROM, recipients, contents)

運行代碼時，出現錯誤：

Exception in Tkinter callback
Traceback (most recent call last):
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-tk/Tkinter.py", line 1410, in __call__
    return self.func(*args)
  File "/Users/BigKids/Desktop/Coding/Python 2/Email/Email Send GUI V1.py", line 112, in send_cmd
    Username_mine = passcheck.Create_Widgets.Username.get()
AttributeError: 'function' object has no attribute 'Username'

預先感謝您的幫助。

編輯這是我的代碼：

#Email Send v3 Program. It has a basic GUI to send emails.

from Tkinter import *
import smtplib
import string
import random

def random_char():
    char_select = random.randrange(52)
    char_choice = string.ascii_letters[char_select]
    return char_choice

class Authen(Frame):
    """Holds authentication code and basic GUI stuff"""
    def __init__(self, master):
        """Start Authen GUI"""
        Frame.__init__(self, master)
        self.grid()
        self.Create_Widgets()

    def Create_Widgets(self):
        """Spawns the widgets"""
        self.Usertext = Label(self, text = "Username: ")
        self.Usertext.grid(row = 0, column = 0)
        self.Username = Entry(self)
        self.Username.grid(row = 0, column = 1)

        self.Passtext = Label (self, text = "Password: ")
        self.Passtext.grid(row = 1, column = 0)
        self.Password = Entry (self, show = "*")
        self.Password.grid(row = 1, column = 1)

        self.Submit = Button(self, text = "Submit Credits",
                        command = self.authen_credits)
        self.Submit.grid()

    def authen_credits(self):
        """Backbone of authen process"""
        Username_mine = self.Username.get()
        Password_mine = self.Password.get()
        server = smtplib.SMTP('smtp.gmail.com:587')
        server.ehlo()
        server.starttls()
        while True:
            try:
                server.login(Username_mine,Password_mine)
                #make my screen dimensions work
                w = 500
                h = 1000
                app = Application()
                app.title("SMTP Mail Client")
                app.geometry("%dx%d" % (w, h))
                break
            except smtplib.SMTPAuthenticationError:
                print "Login Failed"

class Application(Toplevel):
    """Toplevel Frame, holds sendmail stuff"""
    def __init__(self):
        """Start the toplevel Frame"""
        Toplevel.__init__(self)
        self.grid()
        self.entryFun()
        self.mainFun()

    def entryFun(self):
        """Holds entry Frame"""
        self.entryFrame = Frame(self)
        self.entryFrame.grid(row = 0, column = 0, sticky = W)

        self.To_Lbl = Label(self.entryFrame, text = "TO:  ")
        self.To_Lbl.grid(row = 0, column = 0, sticky = W)

        self.To_Entry = Entry(self.entryFrame)
        self.To_Entry.grid(row = 0, column = 1, sticky = W)


        self.Subject_Lbl = Label(self.entryFrame, text = "Subject:  ")
        self.Subject_Lbl.grid(row = 1, column = 0, sticky = W)

        self.Subject_Entry = Entry(self.entryFrame)
        self.Subject_Entry.grid(row = 1, column = 1, sticky = W)

    def mainFun(self):
        """Holds body of thing"""
        self.entryFrame = Frame(self)
        self.entryFrame.grid(row = 1, column = 0, sticky = W)


        self.Body = Text(self.entryFrame, width = 75, height = 50, relief = GROOVE, bd = 5)
        self.Body.grid()

        self.send_mail = Button(self, text = "Send Mail",
                                command = self.send_cmd)
        self.send_mail.grid()

    def send_cmd(self):
        Username_mine = passcheck.Create_Widgets.Username.get()
        Password_mine = passcheck.Create_Widgets.Password.get()
        contents = self.Body.get("0.0", END)
        FROM = "Unknown"
        subject = self.Subject_Entry.get()
        recipients = self.To_Entry.get()
        server = smtplib.SMTP('smtp.gmail.com:587')
        server.ehlo()
        server.starttls()
        server.login()
        server.sendmail(FROM, recipients, contents)

root = Tk()
root.title("Login")
root.geometry("500x500")
passcheck = Authen(root)

root.mainloop()

Answer 1

您會收到錯誤消息，因為Create_Widgets()是Authen類的方法函數，因此其中的self.Username = Entry(self)使Username成為實例的屬性，而不是方法的屬性。 鑒於此，並假設passcheck是這樣的一個實例，我認為您需要編寫：

Username_mine = passcheck.Username.get()

Answer 2

您確定用戶名是函數對象的實際成員嗎？ （確保您在函數類中使用self.Username而不是Username ）

Answer 3

Create_Widgets是一個函數，而不是一個類，因此您無法在其中訪問.Username。

您需要做的是將Authen實例傳遞給Application類，然后將其存儲在self.authen中。 然后，Application中的函數可以執行以下操作：self.authen.Username

通過簡要瀏覽代碼，也許可以修改Application的__init__ ，使其接受“ authen”變量：

def __init__(self, authen):
  # Other stuff.
  self.authen=authen 

然后，您將使用app = Application(authen=self)初始化Application。

在send_cmd() ，您將調用： Username_mine = self.authen.Username.get()