Need a way to exit a loop(something like a interrupt) for PySimpleGUI

I am trying to write a code that functions like the included flow chart, but I have having issues exiting the last loop. Any help is appreciatedProject Flowchart.

We enter the final loop by pressing the defined button defined as 'Start Detection' on PySimpleGui. I want to be able to exit this loop by pressing a button defined as 'Stop Detection' , but without the window.read() function I cannot press the stop detection button and we are in a endless loop. If i include the window.read function the last bit of code will only run once and not in a loop as desired.

Code for the last loop is here:

while(1):

    event,values = window.read()
    if event in (None,'Quit'):
        break
    elif event == 'Filter Settings':
        changefitersettings()
    ## Put in an image for the item detection in here
        print('View the Parking Lot')
    elif event == 'Lot Settings':
        sct_img = sct.grab(bounding_box)
        getcountvalues = changeImage(x,np.array(sct_img))
        Settings()
        print('Lot Settings has been pressed')
        window.close
    elif event =='Start Detection':
        while(1):
            event,values = window.read()
            if event == 'Stop Detection':
                break
            else:
                sct_img = sct.grab(bounding_box)
                videoimage = changeImage(x,np.array(sct_img))
                #cv.imshow('hello1',videoimage[0])
                ServerUpdate = UpdateServer(videoimage[1],videoimage[2],videoimage[3],videoimage[4],videoimage[5],videoimage[6],videoimage[7],videoimage[8],videoimage[9],videoimage[10],videoimage[11],videoimage[12])
                k = cv.waitKey(1) & 0xFF
                # press 'q' to exit
                if k == ord('q'):
                    break
            cv.destroyAllWindows()

It's better to use multithread if you have another job to do and it take long time.

Demo code

import time
import datetime
import threading
import PySimpleGUI as sg

def job(window):
    global running
    while running:
        window.write_event_value('Event', datetime.datetime.now().strftime("%H:%M:%S"))
        time.sleep(0.1)

layout = [[sg.Button('Start'), sg.Button('Stop')]]
window = sg.Window('Threading', layout)
running, old = False, None

while True:

    event, values = window.read()

    if event == sg.WIN_CLOSED:
        running = False
        time.sleep(0.5)
        break

    elif event == 'Start' and not running:
        running = True
        window['Start'].update(disabled=True)
        threading.Thread(target=job, args=(window, ), daemon=True).start()

    elif event == 'Stop':
        running = False
        window['Start'].update(disabled=False)

    elif event == 'Event':
        now = values[event]
        if now != old:
            print(now)
            old = now

window.close()

If we look at the API we see this:

> read
> * THE biggest deal method in the Window class! This is how you get all of your data from your Window. Pass in a timeout (in milliseconds) to wait for a maximum of timeout milliseconds. Will return timeout_key if no other GUI events happen first.
>
>
> read(timeout = None,
> timeout_key = "__TIMEOUT__",
> close = False)
>

Now, the default window.read() means having an infinite timeout, so you see the program basically hanging waiting for the keypress. However, the timeout is the number of milliseconds to wait before returning the timeout_key to your event variable, similar to later when you use cv.waitKey(1). So use something like this:

event,values = window.read(1)

This gives the GUI a chance to read mouse clicks on the "Stop Detection" button.

Also note that there is a method window.perform_long_operation() that does background processing, which might be a neater way of tackling this?