无限while循环python

Question

I am doing a parking sensor with raspberry pi and python

This is the code :

import RPi.GPIO as GPIO
import time
#from picamera import PiCamera
from time import sleep
from gpiozero import MotionSensor
import smtplib

sender = '*****@gmail.com'
reciever = '*****@gmail.com'

def BlueLED (): #Blue LED Function 

    GPIO.output(27, GPIO.HIGH)
    time.sleep(3)
    GPIO.output(27, GPIO.LOW)


def RedLED (): #Red LED Function

    GPIO.output(22,GPIO.HIGH)
    time.sleep(3)
    GPIO.output(22, GPIO.LOW)

def Buzzer (): #Buzzer Function 

    GPIO.output(17, GPIO. HIGH)
    time.sleep(3)
    GPIO.output(17, GPIO.LOW)


def email(sender,reciever,msg):
    try :
        server = smtplib.SMTP('smtp.gmail.com',587)
        server.ehlo()
        server.starttls()
        server.login(sender,'******')
        server.sendmail(sender,reciever,msg)
        server.close()

        print('Email sent!')

    except :
        print('Error')

try :

    GPIO.setmode(GPIO.BCM)
    #camera = PiCamera()
    pir = MotionSensor(4)
    GPIO.setwarnings(False)


    GPIO.setup(27, GPIO.OUT) #blueLED
    GPIO.setup(22, GPIO.OUT) #redLED
    GPIO.setup(17, GPIO.OUT) #buzzer
    GPIO.setup(18, GPIO.OUT) #tempsensor

    GPIO.setup(21, GPIO.IN, pull_up_down = GPIO.PUD_UP) #entry button

    count = 0

    while True :

        if (pir.motion_detected):
            print('Motion Detected')

            #Calling the buzzer function 
            #Buzzer()

            #The content that is going to be sent via email 


            msg = """Subject : Car Park 

            (Picture) """

            email(sender,reciever,msg)




            print('\nPlease press the button for the gate to open')



            while True :

                if(GPIO.input(21) == False):
                    if (count < 5):
                        BlueLED()
                        print('\nThere are ',(5-count), ' parking spaces empty ')

                    else :
                        RedLED()
                        print('\nSorry but the parking is full')

                    count = count + 1



except Exception as ex :
    print('Error occured',ex)

My problem is that the first while loop is not working, ie if the motion sensor is triggered nothing happens yet you can repress the button and the count is increased. I'm guessing there is an easy solution to this but non seem to come to mind. Would love your help, thanks

Answer 1

Your second while loop has no break point!!! Your first while loop runs until it detects motion and then enters the second loop, and your second loop runs forever. If you want both loops to work simultaneously then you should use threads!!! If not then make a break point in second loop.

Simple example:

import time
count=0
count2=0
while True:    #starting first loop 
    count+=1 # counting to 100 to start second loop
    if count==100:
        print("its 100 entering second loop")
        time.sleep(1)
        while True: # entering second loop
            count2+=1 #counting to 100 to exit second loop 
            if count2==100:
                print("its 100 exitin second loop")
                time.sleep(1)
                count=0
                count2=0
                break # exiting second loop this is the break point