recorder.py

import gui_main
import sys 
import numpy 
from PyQt4 import QtCore, QtGui
import PyQt4.Qwt5 as Qwt
import matplotlib
import serial 
import threading


global readervar

def reader(): 
	readervar= True

	ser = serial.Serial(7) #insert COM port number from which data is being collected
	ser.baudrate = 9600 #insert baud rate 
	while True: 
		if readervar: 
			line= ser.readline()
			print (line)
			print(readervar)
		else if uiplot.btn2.clicked(): 
			break
	readervar=False


def shutter(): 
	readervar=False

def main(): 
	global uiplot
	app = QtGui.QApplication(sys.argv)
	win_plot = gui_main.QtGui.QMainWindow()
	uiplot = gui_main.Ui_Form()
	uiplot.setupUi(win_plot)

	uiplot.btn1.clicked.connect(reader)
	uiplot.btn2.clicked.connect(shutter)
	# DISPLAY WINDOWS
	win_plot.show()
	code = app.exec_()

	sys.exit(code)



if __name__ == "__main__":
    main()