Trying to execute a set of functions in order

Question

I am a Python noob, and I'm trying to make a washing device, programming the interface with Python. For now, the machine should work like that:

Wash
Tell washing is complete
Dry
Tell drying is complete

For this, after times for washing/drying are entered, a button is pressed:

button1 = Button(window.tk, command = lambda:main_process(int(varWashtime.get()), int(varDrytime.get())))

def main_process(wash_seconds,dry_seconds):
        wash(wash_seconds)
        stop_wash()
        dry(dry_seconds)
        stop_dry()
        return

def wash(seconds):
    varWashStarted.set("Washing Started") 
    Timer(seconds,idle_fnc).start() 
    return

def stop_wash():
    varWashStarted.set("Washing Stopped")
    Timer(3,idle_fnc,()).start()
    return

def dry(seconds):
    varDryStarted.set("Drying Started")
    Timer(seconds,idle_fnc,()).start()
    return

def stop_dry():
    varDryStarted.set("Drying Stopped")
    return

def idle_fnc():
    pass
    return

Here, I used the function idle_fnc to make threading.Timer properly work.

I found out that I can just use Timer to call other functions after each other, but I would prefer to return from a function, then branch to a new one.

My problem is, as I click the button, the whole thing executes without waiting; I instantly see "Washing Stopped" and "Drying Stopped" on the corresponding label, without the delays triggered.

What is the problem?

Your lines `Timer(seconds,idle_fnc).start()` are not blocking. They just start a thread but the main thread goes on. So your 4 functions are executed consecutively. — S. de Melo, Oct 14 '16 at 08:32
@S.deMelo What is the alternative here, else than `time.sleep()` ? — C K, Oct 14 '16 at 08:34
Take a look at http://stackoverflow.com/questions/19887729/time-delay-tkinter — S. de Melo, Oct 14 '16 at 08:37
Tried that, and it blocks program execution, just like `time.sleep()`. Any other suggestions? — C K, Oct 14 '16 at 08:56
It seems that you have to use a thread: http://stackoverflow.com/a/17016127/6919239 — S. de Melo, Oct 14 '16 at 09:01
@S.deMelo: absolutely not. Threads are definitely the _wrong_ solution here if all you're doing is waiting for a period of time. — Bryan Oakley, Oct 14 '16 at 11:53
search this site for uses of the `after` method on widgets. It lets you schedule some function to run in the future. — Bryan Oakley, Oct 14 '16 at 11:54

Trying to execute a set of functions in order

0 Answers0