[Tutor] Tkinter and threading

[Marco Soldavini]

Hello,
probably this is a very naive question, but I've read some stuff on
Tkinter and its infinite loop.

Then about how can i bind actions to elements, for example buttons.

What if I want to run another loop beside the graphical interface in
the same python script?

For example a state machine with a var state which can have some
discrete string values (like RUNNING, STOPPED, PAUSED, ABORTED, IDLE)
and a text element on the gui that reports that state.

So a button cause a transition > the python loop (not the gui loop)
detects the transition and changes the state var value > the gui
refresh its value on screen.

I wrote some code to try it without threading but it does not give the
expected result as it seems the button update status action is already
triggered. I am missing some basic point here

from Tkinter import *

state = "STOPPED"

root = Tk()

myContainer1 = Frame(root)
myContainer1.pack()
label1=Label(myContainer1, text=state, font = "Helvetica 16 bold italic")
label1.pack()

def change(new_state):
    label1.config(text=new_state)

button1 = Button(myContainer1, text="START")
button1.bind("<Button-1>", change("START"))
button1.pack()
button2 = Button(myContainer1)
button2["text"]= "STOP"
button2.pack()
root.mainloop()


Thanks
marco