pysimpleGUI - creating a thread on the fly

Question

I have created a GUI with PysimpleGUI that has multiple buttons, the intentionss is that users click on a button and continue to work on othe task while the action on the first clicked button is running, and when the action of the clicked button finished, then the thread exits (distroys the current thread),

the code is throwing : RuntimeError: main thread is not in main loop

Can someone help me create the _thread.start_new_thread process and incorporated to the main loop or maybe a solution to avoid RuntimeError

for threading i am using : _thread

the code:

class Windows:

    def newOpenGraph(self, window, event, values):
        '''
        opens a new graph with no problem
        '''

    def newThread(self, window, event, values):

        isRunning = True
        if event == 'OPEN GRAPH':
            _thread.start_new_thread(self.newOpenGraph, (window, event, values ))
        isRunning = False

        while isRunning:
            schedule.run_pending()
            time.sleep(1)

    def mainLayout(self):
        '''
        layout frame work
        '''

        while True:

            event, values = window.read()
            if event == 'OPEN GRAPH':
                # self.newOpenGraph(window, event, values)
                self.newThread(window, event, values)

the image:

Answer 1

Use library schedule in your thread, not in main loop, also no GUI update in your thread.

Maybe code like this,

import time
import _thread
import schedule
import PySimpleGUI as sg

def func(window):
    global i
    window.write_event_value('Update', i)
    i += 1

def new_thread(window, event, values):
    global running
    schedule.every().second.do(func, window=window)
    running = True
    while running:
        schedule.run_pending()
        time.sleep(0.1)

layout = [
    [sg.Button("New"), sg.Button('Exit')],
    [sg.Text('', size=40, key='STATUS')],
]

window = sg.Window("Multithread", layout, finalize=True)
i = 0
threads = []
while True:

    event, values = window.read(timeout=100)

    if event in (sg.WIN_CLOSED, 'Exit'):
        running = False
        break
    elif event == 'New':
        _thread.start_new_thread(new_thread, (window, event, values))
    elif event == 'Update':
        window['STATUS'].update(f'Index {values[event]}')

window.close()