No input possible after tk

Question

If have this piece of code:

import Tkinter as tk
import tkFileDialog

menu = tk.Tk()
res = tkFileDialog.askopenfilename() # un-/comment this line
label = tk.Labe         


        

Answer 1

I've seen reports of this before, I think it's a known bug on windows. You need to let mainloop start before you open a dialog.

If you want the dialog to appear when the app first starts up you can use after or after_idle to have it run after mainloop starts up.

For example:

menu = tk.Tk()
...
def on_startup():
    res = tkFileDialog.askopenfilename()

menu.after_idle(on_startup)
menu.mainloop()

If you don't want any other GUI code to execute until after the dialog, move all your code except for the creation of the root window and call to mainloop into on_startup or some other function.

For example:

def main(filename):
    label = tk.Label(None, text="abc")
    label.grid(row=0, column=0, sticky=tk.W)
    entry = tk.Entry(None)
    entry.grid(row=0, column=1, sticky=tk.EW)

def on_startup():
    res = tkFileDialog.askopenfilename()
    main(filename)

root = Tk()
root.after_idle(on_startup)

Answer 2

askopenfilenamehas it's own event loop. The programm stops, until you selected a filename, and continues afterwards.