如何让我的 tkinter 原型系统计算出正确的总价

我是一名初学者，我正在使用 Tkinter 为 DIY 商店创建一个原型系统，作为我任务的一部分。该应用程序的工作原理是填写一份简单的调查来创建订单。单击“输入数据”按钮后，页面底部应显示您的选择结果，包括总价。

我需要一些关于如何编写系统计算部分的建议，从def total():在代码中，但计算部分位于total_length，这就是我收到“未定义它”错误的地方错误信息 https://i.stack.imgur.com/2je37.png(https://i.stack.imgur.com/w5lZg.png https://i.stack.imgur.com/w5lZg.png).

我不知道如何通过它。我认为它是由我的计算定义的total_length = wallpaper_length_cost * 0.5.

import tkinter as tk
from tkinter import filedialog
from tkinter import ttk

def display_wallpaper_prints():
    window = tk.Toplevel()
    window.title("View Wallpaper prints")
    window.geometry("400x400")
    image_path = "Picture1A.png"
    img = tk.PhotoImage(file=image_path)
    label = ttk.Label(window, image=img)
    label.image = img
    label.pack(side="top", pady=10)


def enter_data():


    full_name = "Name: " + first_name_field.get() + "  " + surname_field.get()
    name_label.config(text=full_name)
    name_label.grid(column=0, row=4, columnspan=2)
    employeeID = "Employee ID: " + employeeID_field.get()
    ID_label.config(text=employeeID)
    ID_label.grid(column=6, row=4, columnspan=2)
    wallpaper_length = "Wallpaper length: " + wallpaper_length_combobox.get()
    wl_label.config(text=wallpaper_length)
    wl_label.grid(column=0, row=5, columnspan=2)
    wallpaper_selection = "Wallpaper selection: " + wallpaper_selection_combobox.get()
    ws_label.config(text=wallpaper_selection)
    ws_label.grid(column=6, row=5, columnspan=2)
    wallpaper_paste = "Wallpaper paste: " + wallpaper_paste_selection_combobox.get()
    wp_label.config(text=wallpaper_paste)
    wp_label.grid(column=0, row=6, columnspan=2)
    extras = "Extras: " + extras_selection_combobox.get()
    extras_label.config(text=extras)
    extras_label.grid(column=6, row=6, columnspan=2)
    lining_paper = "Lining: " + lining_paper_selection_combobox.get()
    lining_paper_label.config(text=lining_paper)
    lining_paper_label.grid(column=0, row=7, columnspan=2)

    print(full_name, employeeID)
    print(wallpaper_length, wallpaper_selection)
    print(extras, wallpaper_paste, lining_paper)


def total_cost():

    wallpaper_per_metre_cost = 0
    if wallpaper_selection_combobox.get() == "Option A (30p per metre)":
        wallpaper_per_metre_cost = 0.30
    elif wallpaper_selection_combobox.get() == "Option B (60p per metre)":
        wallpaper_per_metre_cost = 0.60


    wallpaper_length_cost = 0
    if wallpaper_length_combobox.get() == "10 metres":
        wallpaper_length_cost = 10
    elif wallpaper_length_combobox.get() == "15 metres":
        wallpaper_length_cost = 15
    elif wallpaper_length_combobox.get() == "20 metres":
        wallpaper_length_cost = 20
    elif wallpaper_length_combobox.get() == "25 metres":
        wallpaper_length_cost = 25

    extras_per_metre_cost = 0
    if extras_selection_combobox == "Foil (12p per metre)":
        extras_per_metre_cost = 0.12
    elif extras_selection_combobox == "Glitter (18p per metre)":
        extras_per_metre_cost = 0.18
    elif extras_selection_combobox == "Embossing (6p per metre)":
        extras_per_metre_cost = 0.06

    lining_paper_cost = 0
    if lining_paper_selection_combobox == "Yes, £7.63 per roll":
        lining_paper_cost = 7.63
    elif lining_paper_selection_combobox == "No":
        lining_paper_cost = 0

    wallpaper_paste_cost = 0
    if wallpaper_paste_selection_combobox == "Yes, £13.99 per tub":
        wallpaper_paste_cost = 13.99
    elif wallpaper_paste_selection_combobox == "No":
        wallpaper_paste_cost = 0

    total_length = wallpaper_length_cost.get() * 0.5

    wallpaper_total = wallpaper_per_metre_cost * total_length
    extras_total = extras_per_metre_cost * wallpaper_length_cost
    total_cost = wallpaper_total + extras_total + wallpaper_paste_cost + lining_paper_cost
    total_price = "Total price: £" + total_cost.get()
    total_price_label.config(text=total_price)
    total_price_label.grid(column=0, row=10, columnspan=2)

    print(total_length)
    print(wallpaper_total)
    print(extras_total)
    print(total_price)




window = tk.Tk()
window.title("Wallpapering with Sally")

frame = tk.Frame(window)
frame.pack()

#Customer info details
customer_info_frame = tk.LabelFrame(frame, text="Customer details")
customer_info_frame.grid(row= 0, column= 0, padx= 30, pady= 30)

first_name_label = tk.Label(customer_info_frame, text= "First Name")
first_name_label.grid(row= 0, column= 0)
surname_label = tk.Label(customer_info_frame, text= "Surname")
surname_label.grid(row= 0, column= 2)

first_name_field = tk.Entry(customer_info_frame)
surname_field = tk.Entry(customer_info_frame)
first_name_field.grid(row= 0, column= 1)
surname_field.grid(row= 0, column= 3)

employeeID_label = tk.Label(customer_info_frame, text= "Employee ID")
employeeID_label.grid(row= 1, column= 0)
employeeID_field = tk.Entry(customer_info_frame)
employeeID_field.grid(row= 1, column= 1)

for widget in customer_info_frame.winfo_children():
    widget.grid_configure(padx=30, pady= 30)

#Wallpaper form
wallpaper_frame = tk.LabelFrame(frame)
wallpaper_frame.grid(row=2, column=0)

#Wallpaper Legnth
wallpaper_length_label = tk.Label(wallpaper_frame, text= "How many metres of wallpaper would you like?")
wallpaper_length_combobox = ttk.Combobox(wallpaper_frame, values=["10 metres","15 metres","20 metres","25 metres"])
wallpaper_length_label.grid (row= 1, column= 0, pady= 10)
wallpaper_length_combobox.grid (row= 2, column= 0)


#Wallpaper Selection
wallpaper_selection_label = tk.Label(wallpaper_frame, text= "Which wallpaper would you like?")
wallpaper_selection_combobox = ttk.Combobox(wallpaper_frame, values=["Option A (30p per metre)","Option B (60p per metre)"])
wallpaper_selection_label.grid(row= 3, column= 0, sticky= "news", padx= 15, pady= 10)
wallpaper_selection_combobox.grid(row= 4, column= 0)

#Select Extras
extras_selection = tk.Label(wallpaper_frame, text= "Would you like any of the extras below?")
extras_selection_combobox = ttk.Combobox(wallpaper_frame, values= ["Foil (12p per metre)", "Glitter (18p per metre)", "Embossing (6p per metre)"])
extras_selection.grid(row= 5, column= 0, sticky= "news", padx= 15, pady= 10)
extras_selection_combobox.grid(row= 6, column= 0)


#lining paper combobox
lining_paper_selection = tk.Label(wallpaper_frame, text= "Do you require Lining paper? (20m rolls for £7.63)")
lining_paper_selection_combobox = ttk.Combobox(wallpaper_frame, values=["Yes, £7.63 per roll", "No"])
lining_paper_selection.grid(row= 7, column= 0, sticky= "news", padx= 15, pady= 10)
lining_paper_selection_combobox.grid(row= 8, column= 0)

#wallpaper paste selection
wallpaper_paste_selection = tk.Label(wallpaper_frame, text= "Do you require wallpaper paste? (10kg ready-mixed tubs)")
wallpaper_paste_selection_combobox = ttk.Combobox(wallpaper_frame, values=["Yes, £13.99 per tub", "No"])
wallpaper_paste_selection.grid(row= 9, column= 0, pady= 10, padx= 10)
wallpaper_paste_selection_combobox.grid (row=10, column= 0)

#enter data button
enter_data_button = ttk.Button(frame, text= "Enter Data", command= enter_data)
enter_data_button.grid(row= 3, column= 0, sticky= "news", padx= 20, pady= 20)

#wallpaper_prints_button
wallpaper_prints_button = ttk.Button(wallpaper_frame, text= "View wallpaper prints", command= display_wallpaper_prints)
wallpaper_prints_button.grid(row= 3, column= 1, pady= 10)

final_frame = tk.LabelFrame(frame)
final_frame.grid(row=4, column=0)


name_label = tk.Label(final_frame)

ID_label = tk.Label(final_frame)
wl_label = tk.Label(final_frame)
ws_label = tk.Label(final_frame)
wp_label = tk.Label(final_frame)
extras_label = tk.Label(final_frame)
lining_paper_label = tk.Label(final_frame)
total_price_label = tk.Label(final_frame)




window.mainloop()

我怎样才能让我的 tkinter 原型系统计算出正确的总数 价格

• 在第 17 行添加total_cost() inside enter_data()功能。
• 第 92 行，使用下划线_total_cost =因为重复def total_cost():

snippet:

def enter_data():
    total_cost() # Add this function
    ....
    ....
    ....

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