# 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 "qt_tk_demo.py", line 50 in <module>
#
# This crash happens in _tkinter.c in PythonCmd inside the ENTER_PYTHON macro.

import sys

# Hello-World with PyQt
from PyQt5 import QtWidgets, QtCore
qtapp = QtWidgets.QApplication(sys.argv)
qtwindow = QtWidgets.QWidget()
qtbutton = QtWidgets.QPushButton("Hello Qt", qtwindow)
qtbutton.pressed.connect(lambda:
        QtWidgets.QMessageBox.information(qtwindow,
            "Test Qt", "Qt Button was pressed"))
qtwindow.show()

# Hello-World with Tkinter
import tkinter
from tkinter import messagebox
tkroot = tkinter.Tk()
tkroot.withdraw()
tkwindow = tkinter.Toplevel(tkroot)
tkinter.Button(tkwindow, text="Hello Tk", command=lambda:
        messagebox.showinfo("Test Tk", "Tk Button was pressed")).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)

# Feed Tkinter event loop from Qt
timer = QtCore.QTimer()
def update_tk():
    tkroot.update()
    timer.start()
timer.timeout.connect(update_tk)
timer.setSingleShot(True)
timer.start(50)

# Run Qt application
sys.exit(qtapp.exec_())