Why ttk Progressbar appears after process in Tkinter

Question

I want to create a large text upon Tkinter menu command and provide visual support by a progress bar. Although the progress bar is meant to start before the sub

Answer 1

Here's another considerably simpler solution that doesn't require mixing Tkinter and multi-threading. To use it requires the ability to call the progressbar widget's update_idletasks() method multiple times during the time-consuming function.

from Tkinter import *
import ttk

import time

def foo(progressbar):
    progressbar.start()
    for _ in range(50):
        time.sleep(.1) # simulate some work
        progressbar.step(10)
        progressbar.update_idletasks()
    progressbar.stop()

root = Tk()

mainframe = ttk.Frame(root, padding="3 3 12 12")
mainframe.grid(column=0, row=0, sticky=(N, W, E, S))
mainframe.columnconfigure(0, weight=1)
mainframe.rowconfigure(0, weight=1)
progressbar = ttk.Progressbar(mainframe, mode='indeterminate')
progressbar.grid(column=1, row=100, sticky=W)

ttk.Button(mainframe, text="Check",
           command=lambda:foo(progressbar)).grid(column=1, row=200, sticky=E)

for child in mainframe.winfo_children():
    child.grid_configure(padx=5, pady=5)
root.bind('', lambda event:foo(progressbar))

root.mainloop()