How to stop a while loop with a user input without interrupting the program?

Question

How do I infinitely loop 5 led lights to keep turning on one after the other until the user inputs something? I don't want the user input to interrupt the loop. Right now everything works well except that in the middle of the loop the input interrupts the program.

import time
import RPi.GPIO as GPIO
GPIO.setmode(GPIO.BCM)

print("Press h to exit the program")

while True:

    GPIO.setup(19,GPIO.OUT)
    GPIO.output(19,True)
    time.sleep(0.5)
    GPIO.output(19,False)

    GPIO.setup(26,GPIO.OUT)
    GPIO.output(26,True)
    time.sleep(0.5)
    GPIO.output(26,False)

    GPIO.setup(22,GPIO.OUT)
    GPIO.output(22,True)
    time.sleep(0.5)
    GPIO.output(22,False)

    GPIO.setup(27,GPIO.OUT)
    GPIO.output(27,True)
    time.sleep(0.5)
    GPIO.output(27,False)

    GPIO.setup(17,GPIO.OUT)
    GPIO.output(17,True)
    time.sleep(0.5)
    GPIO.output(17,False)

    x = input("")

    if (x == "h"):
        print("Exiting the program")
        break

    GPIO.setwarnings(False)

GPIO.cleanup()

Your question has nothing to do with the raspberry-pi. When asking questions here, it's always best to provide a runnable [mre] and leave _everything_ out of it that's irrelevant. — martineau, Mar 21 '21 at 23:48

score 0 · Accepted Answer · edited Mar 21 '21 at 23:44

0

You can use the third-party keyboard library to do this quite easily.

import keyboard

while True:
    print(1)
    print(2)
    print(3)
    print(4)
    if keyboard.is_pressed("h"):
       break

edited Mar 21 '21 at 23:44

martineau

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answered Mar 21 '21 at 23:42

PacketLoss

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Thanks for your help. I tried what you suggested but I've got a ModuleNotFoundError: No module named 'keyboard' error. Is there a way to fix this? Thanks – John lewis Mar 21 '21 at 23:53
Since its a third party library you need to install it first. `pip install keyboard` – PacketLoss Mar 21 '21 at 23:54
Apparently I had to do sudo pip3 install keyboard although I still have errors. – John lewis Mar 22 '21 at 00:09
Traceback (most recent call last): raise ImportError('You must be root to use this library on linux.') ImportError: You must be root to use this library on linux. – John lewis Mar 22 '21 at 21:04
1

@Johnlewis https://stackoverflow.com/q/48796147/7942856 – PacketLoss Mar 22 '21 at 22:43

How to stop a while loop with a user input without interrupting the program?

1 Answers1