# This is a minimal example to demonstrate a crash on resizing a Tkinter
# window on Windows, if Tkinter doesn't own the main loop.
#
#   Fatal Python error: PyEval_RestoreThread: NULL tstate
#
#   Current thread 0x00001140 (most recent call first):
#     File "simple_tk_demo.py", line 33 in <module>
#
# This crash happens in _tkinter.c in PythonCmd inside the ENTER_PYTHON macro.

# Hello-World with Tkinter
import tkinter
from tkinter import messagebox
tkroot = tkinter.Tk()
tkroot.withdraw()
tkwindow = tkinter.Toplevel(tkroot)
tkinter.Label(tkwindow, text="Hello Tk").pack()

# Bind the tkwindow <Configure> event
def on_tk_configure(event):
    print(event)
    color = '#{:02x}{:02x}{:02x}'.format(event.width % 0xFF,
            event.height % 0xFF, event.x % 0xFF)
    tkwindow.config(bg=color)
tkwindow.bind("<Configure>", on_tk_configure)

# Update once so that the dialog is shown
tkroot.update()

# Show a native Windows dialog
import ctypes
MessageBox = ctypes.windll.user32.MessageBoxW
MessageBox(None, 'Hello', 'Window title', 0)