[Python] Unexpected Tkinter GUI behavior when run in Spyder (iPython) console, but not in...

I'm getting a strange problem. I recently converted a project from Mac to Windows and noticed some strange tkinter GUI issues that occur only on my Windows 11 platform, despite not changing python code at all. I've isolated the issue to a simplified code included below.

import tkinter as tk
def on_check():
if check_var.get() == 1:
print("Checkbox is checked.")
else:
print("Checkbox is unchecked.")

root = tk.Tk()
root.title("Checkbox Example")

check_var = tk.IntVar(value=0) # starts off as unchecked (0)
checkbox = tk.Checkbutton(root, text="Do Something", variable=check_var, command=on_check)
checkbox.pack()

root.mainloop()



For some reason, whever I run the GUI in Spyder, the IntVar is not updating and the code simply returns "Checkbox is unchecked." every time the button is pressed. However, when I run the program using the terminal, it works exactly as expected, where the printed lines will read checked/unchecked according to the checkbox status. Any idea wht this might be happening?

I've seen that similar issues can occur in iPython since the event handling is different than in a standalone interpreter, and that this can be helped by adjsuting the mainloop call as follows.

if __name__ == '__main__':
root.mainloop()



However, this made no difference in my case. It doesn't appear to be related to the python version either. I've created new environents with all the following python versions, to no avail.

• 3.8.20
• 3.9.21
• 3.10.16
• 3.11.11
• 3.12.9
• 3.13.2

Am I missing something about the Spyder/iPython console settings that is causing this issue?

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