python - Input with time limit/countdown

4
votes

I'm pretty new to Python and would like to write a (not computer) language trainer for my students. Just something like where a timer runs in the background and the student has to input words quickly to slow down/revert the countdown - otherwise the countdown reaches zero and displays some "game over" message. (Just like when a special agent has to defuse a bomb while the timer races towards zero.)

There are tons of explanations of threading which sounds like the right way to do it, sure, but so far I haven't found anything where a timer is combined with a (time-limited) raw_input. Could any of you pros give me a pointer to the tutorial/discussion I have overlooked?

2
pythonmultithreadinginput

2 Answers

4
votes
import threading
import time
import os

def ask():
    """
    Simple function where you ask him his name, if he answers
    you print message and exit
    """
    name = raw_input("Tell me your name, you have 5 seconds: ")
    exit_message = "Wohoho you did it..Your name is %s" % name
    exit(exit_message)

def exit(msg):
    """
    Exit function, prints something and then exits using OS
    Please note you cannot use sys.exit when threading..
    You need to use os._exit instead
    """
    print(msg)
    os._exit(1)

def close_if_time_pass(seconds):
    """
    Threading function, after N seconds print something and exit program
    """
    time.sleep(seconds)
    exit("Time passed, I still don't know your name..")

def main():
    # define close_if_time_pass as a threading function, 5 as an argument
    t = threading.Thread(target=close_if_time_pass,args=(5,))
    # start threading
    t.start()
    # ask him his name
    ask()

if __name__ == "__main__":
    main()
0
votes

You don't have to do it via threading, you could in a single thread run through your 'logic' at a specific frequency and each iteration recalculate the countdown via a time-delta method. This is how many video games are produced.

Lets say you run this pseudo-code method at 60hz:

delta = timenow-timelast;
countdown -= delta;
if(input)
    processInputHere;

You should be able to convert the pseudo-code to python code to make it work