python - TkInter error: no display name and no $DISPLAY environment variable

Question

I'm working on TkInter on Repl.it and have run into a problem, this is my code:

from tkinter import *
import tkinter as tk

root = tk.Tk()
root.geometry('400x400')

I run into this error:

Traceback (most recent call last):
  File "main.py", line 4, in <module>
    root = tk.Tk()
  File "/usr/local/lib/python3.7/tkinter/__init__.py", line 202
3, in __init__
    self.tk = _tkinter.create(screenName, baseName, className,
interactive, wantobjects, useTk, sync, use)
_tkinter.TclError: no display name and no $DISPLAY environment
variable

How do I solve this?

Answer 1

You're apparently trying to do this with repl.it's "Python", which doesn't support the display that tkinter needs. They do offer a separate "Tkinter" option, although it's quite far down the list of languages. Here's a shortcut: https://repl.it/languages/tkinter

There you don't get that error. In order to actually get the window shown, you'll have to also add this under your current code:

root.mainloop()

Demo