python - textvariable not found in a def

Question

I have this code :

from tkinter import *

def mine():
    global textVar
    textVar = StringVar()
    textVar.set('Text')


root = Tk()

root.title('Miner v1.0')
root.geometry('400x240')

miningButton = Button(root, text='Mine', command=mine)
miningButton.pack()

mainLabel = Label(root, textvariable=textVar)
mainLabel.pack()

root.mainloop()

I have made textVar a global variable but the mainLabel it don't find it, it says that it is undefined. But when the textVar is outside the def it works

Answer 1

It's because you never execute the mine function, so textVar variable has never existed. You can just create the variable outside the function.

from tkinter import *

root = Tk()

root.title('Miner v1.0')
root.geometry('400x240')

textVar = StringVar()
def mine():
    textVar.set('Text')

miningButton = Button(root, text='Mine', command=mine)
miningButton.pack()

mainLabel = Label(root, textvariable=textVar)
mainLabel.pack()

root.mainloop()