无法计算项目的总金额答案

【问题标题】：Having trouble for calculating total amount of Items无法计算项目的总金额
【发布时间】：2020-12-17 08:45:17
【问题描述】：

我无法理解为什么我列表中的前 2 项中的某些项目没有被计算。我错过了什么？

代码：

from tkinter import *
root = Tk()
root.geometry('300x200')
root.title("Grade Calculator")

def exitProgram():
root.destroy()

def  calculate():
    totalcost = 0
    if CheckVar1.get() == 1:
        totalcost += 10
    if CheckVar2.get() == 1:
        totalcost += 2.50
    if CheckVar3.get() == 1:
        totalcost += 4
        label_2.config(text="Total cost: $"+str(totalcost))

CheckVar1 = IntVar()
CheckVar2 = IntVar()
CheckVar3 = IntVar()

label_1 = Label(root, text="Select from the menu: ",font=

("粗体", 10)) label_1.place(x=20,y=10)

Checkbutton(root, text = "Premium Whapper ($10.0)", variable = CheckVar1, onvalue = 1, offvalue = 0).place(x=50,y=40)
Checkbutton(root, text = "Inca cola ($2.50)", variable = 
CheckVar2, onvalue = 1, offvalue = 0).place(x=50,y=65)
Checkbutton(root, text = "Smash potatoes ($4.0)", variable 
= CheckVar3, onvalue = 1, offvalue = 0).place(x=50,y=90)
label_2 = Label(root, text="Total cost: $0 ",font=("bold", 
10))
label_2.place(x=30,y=120)

Button(root, text='Calculate 
Cost',command=calculate).place(x=20,y=150)
Button(root, text='Quit',width="7", 
command=exitProgram).place(x=130,y=150)

root.mainloop()

【问题讨论】：

你的输入是什么，预期的输出是什么，你得到的输出是什么？
嗨，它显示了 3 个项目及其相应的价格。勾选时不计算第一项和第二项。
好的，我试试
不，不工作。

标签： python python-3.x tkinter pyzo

【解决方案1】：

只有在 CheckVar3 为真时才设置标签：

if CheckVar3.get() == 1:
    totalcost += 4
    label_2.config(text="Total cost: $"+str(totalcost))

由于您的缩进有问题，应该是：

if CheckVar3.get() == 1:
    totalcost += 4

label_2.config(text="Total cost: $"+str(totalcost))

【讨论】：

【解决方案2】：

您有大量的缩进错误和中断的控制流程！无论如何，这是工作代码：

from tkinter import *

def exitProgram():
    root.destroy()

def calculate():
    global label_2, totalcost
    if CheckVar1.get() == 1:
        totalcost += 10
    if CheckVar2.get() == 1:
        totalcost += 2.50
    if CheckVar3.get() == 1:
        totalcost += 4
    label_2.config(text="Total cost: $"+str(totalcost))

totalcost = 0
root = Tk()
root.geometry('300x200')
root.title("Grade Calculator")

CheckVar1 = IntVar()
CheckVar2 = IntVar()
CheckVar3 = IntVar()

label_1 = Label(root, text="Select from the menu: ",font=("bold", 10))
label_1.place(x=20,y=10)

Checkbutton(root, text = "Premium Whapper ($10.0)", variable = CheckVar1, onvalue = 1, offvalue = 0).place(x=50,y=40)
Checkbutton(root, text = "Inca cola ($2.50)", variable =CheckVar2, onvalue = 1, offvalue = 0).place(x=50,y=65)
Checkbutton(root, text = "Smash potatoes ($4.0)", variable= CheckVar3, onvalue = 1, offvalue = 0).place(x=50,y=90)
label_2 = Label(root, text="Total cost: $0 ",font=("bold",10))
label_2.place(x=30,y=120)

Button(root, text='Calculate Cost',command=calculate).place(x=20,y=150)
Button(root, text='Quit',width="7",command=exitProgram).place(x=130,y=150)

root.mainloop()

【讨论】：