如何修复Tkinter帧控制器密钥错误?

Question

我是python的新手，我正在尝试使用RFID创建登录名。 我开始使用许多顶级窗口创建一个简单的 GUI，但我想只在一个窗口中创建一个 GUI，控制器解决了它。现在我遇到了一个问题，因为我正在尝试获取变量"id"的值并将其用作从数据库中获取数据的参考。

这是我的代码。

class Kiosk(Tk):
def __init__(self, *args, **kwargs):
Tk.__init__(self, *args, **kwargs)
self.title_font = tkfont.Font(family='Helvetica', size=18, weight="bold", slant="italic")
GPIO.setwarnings(False)
container = Frame(self)
container.pack(side="top", fill="both", expand=True)
container.grid_rowconfigure(0, weight=1)
container.grid_columnconfigure(0, weight=1)
self.style = Style()
self.style.theme_use('alt')
self.style.map('TCombobox', fieldbackground=[('readonly','white')])
self.db = pymysql.connect(host = "192.168.1.11",port = 3306, user = "root",passwd = "justin",db= "thesis_db")
self.cursor = self.db.cursor()
self.QueryResident = "CREATE TABLE IF NOT EXISTS residents_db (FIRST_NAME varchar(255) not null, MIDDLE_NAME varchar(255) not null, LAST_NAME varchar(255) not null,SEX varchar(255) not null, BIRTH_DATE date, CIVIL_STATUS varchar(255) not null, PLACE_OF_BIRTH varchar(255) not null, RFID varchar(255) not null)"
self.cursor.execute(self.QueryResident)
self.frames = {}
for F in (Start_Page, Registration_Page_Admin, Registration_Page_User, Update_User, Update_Admin, Login_RFID, main_page):
page_name = F.__name__
frame = F(parent=container, controller=self)
self.frames[page_name] = frame
frame.grid(row=0, column=0, sticky="nsew")
self.show_frame("Start_Page")
def show_frame(self, page_name):
frame = self.frames[page_name]
frame.tkraise()
def get_page(self, page_class):
return self.frames[page_class]
class Start_Page(Frame):
def __init__(self, parent, controller):
Frame.__init__(self, parent)
self.controller = controller
label = Label(self, text="Login", font=controller.title_font)
label.pack(side="top", fill="x", pady=10)
button1 = Button(self, text="Login",
command=lambda: controller.show_frame("Login_RFID"))
button1.pack()
class Login_RFID(Frame):
def __init__(self, parent, controller):
Frame.__init__(self, parent)
self.parent = parent
self.controller = controller
self.get_Firstn1 = None
self.img_login = (Image.open("Scan_RFID.png"))
self.image_login = self.img_login.resize((550,417))
self.img_background_login = ImageTk.PhotoImage(self.image_login)
self.db = pymysql.connect(host = "192.168.1.11",port = 3306, user = "root",passwd = "justin",db= "thesis_db")
self.cursor = self.db.cursor()
label_login = Label(self, image = self.img_background_login) 
label_login.pack(fill="both", expand = 1)
label_login.bind('<Enter>',self.login_RFID)

def login_RFID(self, event):
self.reader = SimpleMFRC522()
self.id, self.text = self.reader.read()
self.cursor.execute("SELECT * FROM residents_admin WHERE RFID = %s",str(self.id))
if (self.cursor.fetchone() is not None): 
self.controller.show_frame("main_page")
qwe = False
else:
self.cursor.execute("SELECT * FROM residents_db WHERE RFID = %s", str(self.id))
if (self.cursor.fetchone() is not None): 
self.controller.show_frame("main_page")
qwe = False
else:
messagebox.showerror("Warning!","Your RFID card is not yet registered!")
def get_data(self):
self.cursor.execute("SELECT * FROM residents_admin WHERE RFID = %s",str(self.id))
if (self.cursor.fetchone() is not None): 
self.cursor.execute("SELECT FIRST_NAME FROM residents_admin WHERE RFID = %s", str(self.id))
self.get_Firstn = self.cursor.fetchone()
self.get_Firstn1 = str(self.get_Firstn[0])
self.cursor.execute("SELECT MIDDLE_NAME FROM residents_admin WHERE RFID = %s", str(self.id))
self.get_Middlen = self.cursor.fetchone()
self.get_Middlen1 = str(self.get_Middlen[0])
self.cursor.execute("SELECT LAST_NAME FROM residents_admin WHERE RFID = %s", str(self.id))
self.get_Lastn = self.cursor.fetchone()
self.get_Lastn1 = str(self.get_Lastn[0])
self.cursor.execute("SELECT BIRTH_DATE FROM residents_admin WHERE RFID = %s", str(self.id))
self.get_Birthd = self.cursor.fetchone()
self.get_Birthd1 = str(self.get_Birthd[0])
self.cursor.execute("SELECT PLACE_OF_BIRTH FROM residents_admin WHERE RFID = %s", str(self.id))
self.get_Placeb = self.cursor.fetchone()
self.get_Placeb1 = str(self.get_Placeb[0])
self.cursor.execute("SELECT CIVIL_STATUS FROM residents_admin WHERE RFID = %s", str(self.id))
self.get_Civils = self.cursor.fetchone()
self.get_Civils1 = str(self.get_Civils[0])
self.cursor.execute("SELECT SEX FROM residents_admin WHERE RFID = %s", str(self.id))
self.get_Sex = self.cursor.fetchone()
self.get_Sex1 = str(self.get_Sex[0])
class main_page(Frame):
def __init__(self, parent, controller):
Frame.__init__(self, parent)
self.controller = controller
label = Label(self, text="Welcome", font=controller.title_font)
label.pack()
login_rfid_page = self.controller.get_page("Login_RFID")
login_rfid_page.get_data(None)
value = login_rfid_page.get_Firstn1
print(value)
button1 = Button(self, text="Register User",
command=lambda: self.controller.show_frame("Registration_Page_User"))
button2 = Button(self, text="Register Admin",
command=lambda: self.controller.show_frame("Registration_Page_Admin"))
button3 = Button(self, text="Update User",
command=lambda: self.controller.show_frame("Update_User"))
button4 = Button(self, text="Update Admin",
command=lambda: self.controller.show_frame("Update_Admin"))
button1.pack()
button2.pack()
button3.pack()
button4.pack()

这是我的错误。

Exception in Tkinter callback
Traceback (most recent call last):
File "/usr/lib/python3.7/tkinter/__init__.py", line 1705, in __call__
return self.func(*args)
File "/home/pi/Thesis/qweqweqweq.py", line 85, in login_RFID
self.controller.show_frame("main_page")
File "/home/pi/Thesis/qweqweqweq.py", line 45, in show_frame
frame = self.frames[page_name]
KeyError: 'main_page'

我想我在扫描我的 RFID 时没有任何问题。我只需要将扫描的RFID的值从id获取到主页，以将其用作获取所需数据的参考。

我遵循了布莱恩·奥克利爵士在这里回答的解决方案，以及他对其他问题的其他回答。我读了一整夜，不知何故，我明白他对他的回答是什么意思，只是不知道为什么我做不到。

希望你们能帮到我。我修剪了上面的代码，并提供了与错误相关的唯一代码。 谢谢！

Answer 1

首先：您必须使用self.id而不是id才能从不同位置访问id

def login_RFID(self, event):
self.reader = SimpleMFRC522()
self.id, self.text = self.reader.read()  # self.id

第二：您必须在main_page中运行此函数才能获得正确的值

login_rfid_page = self.controller.get_page("Login_RFID")
login_rfid_page.login_RFID(None)  # run scanner
value = login_rfid_page.id
print(value)