I created a tkinter python tally app and i just want to be able to plus 1 or minus 1 from the click of a button. Just a regular tally app. The problem im having is that the plus 1 always works but when i want to minus 1 it automatically turns to a negative number. here is my script:

total_count = 0

def count_number():
    global total_count
    total_count = total_count   1
    count_label["text"] = total_count


minus_count = total_count

def minus_number():
    global minus_count
    minus_count = minus_count - 1
    count_label["text"] = minus_count


count_label = Label(root, fg="orange", font="Verdana 150 bold italic")
count_label.pack()
count_label.place(x=810, y=280)



plus_button = Button(root, text="  1", width=10, fg="purple", command=count_number).place(x=910, y=870)
minus_button = Button(root, text="- 1", width=10, fg="purple", command=minus_number).place(x=910, y=970)

How can i both add and subtract 1 from the same number?

CodePudding user response：

At the line minus_count = total_count minus_count is assigned the value of total_count which is 0. So these events occur in order:

1. total_count = 0
2. minus_count = 0
3. plus is executed, which increases total_count, not minus_count
4. minus is executed which subtracts 1 from minus_count, resulting in -1

Easy fix will be to use the same variable in both places:

total_count = 0

def count_number():
    global total_count
    total_count = total_count   1
    count_label["text"] = total_count


def minus_number():
    global total_count
    total_count= total_count- 1
    count_label["text"] = total_count


count_label = Label(root, fg="orange", font="Verdana 150 bold italic")
count_label.pack()
count_label.place(x=810, y=280)



plus_button = Button(root, text="  1", width=10, fg="purple", command=count_number).place(x=910, y=870)
minus_button = Button(root, text="- 1", width=10, fg="purple", command=minus_number).place(x=910, y=970)