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Change the value of a variable with a button (Tkinter)

I want to change the value of a variable just with a button, i don’t want to create a new entire function just like that:

from Tkinter import *
variable = 1
def makeSomething():
    global variable
    variable = 2
root = Tk()
myButton = Button(root, text='Press me',command=makeSomething).pack()

How i can do that? (I need to do that for six buttons, making six functions it’s not an option)

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Answer

i need to make this for 6 buttons…

If each button modifies the same global variable, then have makeSomething accept a value parameter:

from Tkinter import *
variable = 1
def makeSomething(value):
    global variable
    variable = value
root = Tk()
Button(root, text='Set value to four',command=lambda *args: makeSomething(4)).pack()
Button(root, text='Set value to eight',command=lambda *args: makeSomething(8)).pack()
Button(root, text='Set value to fifteen',command=lambda *args: makeSomething(15)).pack()
#...etc

If each button modifies a different global, then condense all your globals into a single global dict, which makeSomething can then modify.

from Tkinter import *
settings = {"foo": 1, "bar": 1, "baz": 1}

def makeSomething(name):
    settings[name] = 2

root = Tk()
Button(root, text='Set foo',command=lambda *args: makeSomething("foo")).pack()
Button(root, text='Set bar',command=lambda *args: makeSomething("bar")).pack()
Button(root, text='Set baz',command=lambda *args: makeSomething("baz")).pack()
#...etc

In either case, you still only require one function.


By the way, don’t do this:

myButton = Button(root).pack()

This assigns the result of pack() to myButton, so myButton will be None instead of referring to your button. Instead, do:

myButton = Button(root)
myButton.pack()
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