Clock.schedule_once in kivy works as intended ONLY when runtime of previous function is short bug

Question

.kv file

#:import Clock kivy.clock.Clock
#:import threading threading
#:import partial functools.partial



<MainScreen>:
    BoxLayout:
        size: root.size
        orientation: "vertical"
        BoxLayout:
            Label:
                id: wordcount
                pos_hint: {'center_x':0.5,'y':0.6}
                size_hint: 0.2,0.2
                text: root.wordcount 
            Label:
                pos_hint: {'center_x':0.5,'y':0.6}
                size_hint: 0.2,0.2
                id: BESTOPTIONS
                text: root.entrophyvaluesbest     
             
        CustomBox:
            id: layout
            cols:5
        Button:
            pos_hint: {'center_x':0.5,'y':0.67}
            size_hint: 0.5,0.1
            text: "Click here to start!"
            on_release: root.StartGame()
        Button:
            text: "Check your word!"
            size_hint: 0.5,0.1
            pos_hint:{'center_x':0.5,'y':0.4}
            on_press: 
                a=threading.Thread(target=root.Check)
                a.start()
                a.join()
                b=threading.Thread(target=root.ShowPreviousWord)
                b.start()
                b.join()
                c=threading.Thread(target=root.ClearLetters)
                c.start()
                c.join()
                d=threading.Thread(target=partial(Clock.schedule_once,root.FocusFirst,0.5))
                d.start()
                
        Label:
            pos_hint:{'center_x':0.5,'y':-0.35}
            id: OUTPUT
            markup: True

My .py code is long, so I will try asking without that - My functions which occur while I click Button "Check your word" are sometimes taking to long - if the function a ( it is the only time consuming function there) takes too much time, then the Clock.schedule_once doesn't proc the FocusFirst function and because of that - nothing is focused then. I want to change the focus after all functions takes place - I know that main gui is in Main Thread, so it's not happening because of that, but I wonder if I am able to just make all functions happen first and then just change the focus and if so - how to do that.

I tried adding Clock.schedule_once without time argument, which makes it even worse.

I know that I can fix it by adding bigger time - for example 30 seconds, but I want the TextInput focus right after functions happen, not 30 seconds after that.

Answer 1

I resolved the issue and probably resolved the issue of GUI change block by some functions.

I simply took the function out of on_press and placed it to on_release, the button is being locked untill functions inside happen, then the button is released, so the function I wanted to postpone happens.