Python program that demonstrates how to run many simultaneous Windows using PySimpleGUI. Works with PySimpleGUI, PySimpleGUIQt, but has a bug with PySimpleGUIWx.

MultiWindowNetworkSimulation.py

import PySimpleGUI as sg
from random import randint as randint
from random import choice as choice
import time
import string

"""
    PySimpleGUI simulation of a network communications monitoring and manipulation of network connections
    10 lines of Network connections are shown
    Can click on a button to bring up a detailed view for the connection
    In the detailed view can take actions on the connection or close the detailed view
    MUCH of this code is in creating the random values for names, input/output stats, etc
    The important overall architecture is:
             Mainwindow runs every 100 ms
             If 'detail' button is clicked in main window
                 A new "detail" window is created
             All active "detail" windows are processed at the end of the main event loop (every 100ms)
             Optional POLL_TIME paramter can be used to
"""

NUM_CONNECTIONS = 10
POLL_TIME = 100

def initialize_window(name, slot):
    """
    Starts up a detailed window
    :param name: Text name of the connection
    :param slot: The "Slot Number" of the conection
    :return: window: The PySimpleGUI Window object for this window
    """
    layout = [
                [sg.Text(str(name) + ' Detailed Information')],
                [sg.Text('Input bytes '), sg.Text('', key='_INPUT_BYTES_')],
                [sg.Text('Output bytes '), sg.Text('', key='_OUTPUT_BYTES_')],
                [sg.Text('', size=(20,1), key='_ACTION_RESULT_')],
                [sg.Button('Action 1'), sg.Button('Action 2'), sg.Button('Close')],
             ]
    window = sg.Window('Details '+ str(name),location=(225*slot, 0)).Layout(layout)
    return window


def process_window(window:sg.Window):
    """
    Processes events, button clicks, for a detailed window
    :param window: The PySimpleGUI Window to work with
    :return: event: The button clicked or None if exited
    """
    event, values = window.Read(timeout=0)          # Read without waiting for button clicks
    if event in (None, 'Close'):
        window.Close()
        return None
    elif event == 'Action 1':
        window.Element('_ACTION_RESULT_').Update('Action 1 result = '+str(randint(0,1000)))
    elif event == 'Action 2':
        window.Element('_ACTION_RESULT_').Update('Action 2 result = '+str(randint(-1000,0)))
    # show dummy stats so can see window is live and operational
    window.Element('_INPUT_BYTES_').Update(randint(0,40000))
    window.Element('_OUTPUT_BYTES_').Update(randint(0,40000))
    return event        # return the button clicked


def main_window():
    """
    Runs the main window
    :return:
    """
    # create the GUI elements for each possible connection
    connection_rows = []
    for i in range(NUM_CONNECTIONS):
        connection_rows.append([sg.Text('', size=(12,1), key='_TEXT_'+str(i)),
                            sg.Button('Details', key='_DETAILS_'+str(i))],)
    # The main window layout
    layout = [ [sg.Text('Active Network Connections')],
                *connection_rows,
               [sg.Button('Exit')]]

    window = sg.Window('Main Window').Layout(layout)

    # Loop reading events from a network connection
    active_connectios = [None for i in range(NUM_CONNECTIONS)]      # list of active connections (names)
    detail_window_list = [None for i in range(NUM_CONNECTIONS)]     # list of detailed windows that are open
    start_time = time.time()
    # MAIN WINDOW EVENT LOOP
    while True:
        # ----------------------------- Process Main Window -----------------------------

        event, values = window.Read(timeout=POLL_TIME)      # run main window every 100ms
        if event in (None, 'Exit'):
            break
        print(event) if event != sg.TIMEOUT_KEY else None
        # Process Details Button Click
        if event.startswith('_DETAILS_') and active_connectios[int(event[-1])]:
            slot = int(event[-1])
            if active_connectios[slot]:
                if detail_window_list[slot] is None:
                    detail_window_list[slot] = initialize_window(active_connectios[slot], slot)
        # ------------------- Simulate Network Activity Every 3 seconds ----------------
        time_delta = round(time.time() - start_time)
        if time_delta % 3 == 0:
            slot = randint(0,NUM_CONNECTIONS-1)
            active_connectios[slot] = ''.join([choice(string.ascii_lowercase) for i in range(5)]) if randint(0,5) else ''
            window.Element('_TEXT_'+str(slot)).Update(active_connectios[slot])
        # -------------------------- Process all Detailed Windows ----------------------
        for i in range(len(detail_window_list)):
            if detail_window_list[i]:
                rc = process_window(detail_window_list[i])
                if rc is None:        # if closed then remove the window for active list
                    detail_window_list[i] = None
    # After the Event Loop
    window.Close()

if __name__ == '__main__':
    main_window()