How to open a new window and destroy the current one?

[divadsn]

When I open the new window using mainloop() the code works just fine, but all async functions stop working.

But when I try the same using async_mainloop() it crashes immediately after one second with a stack trace:

2025-04-05 19:11:06,692 - asyncio - ERROR - Task exception was never retrieved
future: <Task finished name='Task-4' coro=<LoginWindow.login() done, defined at C:\Users\David\PycharmProjects\evelstar-invoices-app\invoices_app\views\login_window.py:57> exception=RuntimeError('This event loop is already running')>
Traceback (most recent call last):
  File "C:\Users\David\PycharmProjects\evelstar-invoices-app\invoices_app\views\login_window.py", line 100, in login
    invoices_window.async_mainloop()
  File "C:\Users\David\AppData\Local\pypoetry\Cache\virtualenvs\evelstar-invoices-app-edsiHra2-py3.12\Lib\site-packages\async_tkinter_loop\mixins.py", line 26, in async_mainloop
    super().async_mainloop()
  File "C:\Users\David\AppData\Local\pypoetry\Cache\virtualenvs\evelstar-invoices-app-edsiHra2-py3.12\Lib\site-packages\async_tkinter_loop\mixins.py", line 9, in async_mainloop
    async_mainloop(self)
  File "C:\Users\David\AppData\Local\pypoetry\Cache\virtualenvs\evelstar-invoices-app-edsiHra2-py3.12\Lib\site-packages\async_tkinter_loop\async_tkinter_loop.py", line 49, in async_mainloop
    get_event_loop().run_until_complete(main_loop(root))
  File "C:\Users\David\AppData\Local\Programs\Python\Python312\Lib\asyncio\base_events.py", line 663, in run_until_complete
    self._check_running()
  File "C:\Users\David\AppData\Local\Programs\Python\Python312\Lib\asyncio\base_events.py", line 622, in _check_running
    raise RuntimeError('This event loop is already running')
RuntimeError: This event loop is already running
C:\Users\David\AppData\Local\Programs\Python\Python312\Lib\asyncio\base_events.py:1972: RuntimeWarning: coroutine 'main_loop' was never awaited
  handle = self._ready.popleft()

[insolor]

In tkinter (not only in async-tkinter-loop library context) you don't delete the original main window. You just hide it. And other windows are created as Toplevel objects without running of a new mainloop.

[divadsn]

Ahh, now I got it, thank you! 😄