How to create a list and append to list inside a mqtt and GUI program?

[Spencer Du]

Hi 

I have code for GUI and MQTT. In GUI.py I have "def loadGUI" which loads up a GUI file if the file exists in current directory. I want to add the file name to a list when a file is imported and for each subsequent file that is imported I want the file name to be imported to the same list and print the list or create a new list but with the imported file named added to list which has the existing file names that have already been imported. I was wondering how I do this. By the way run GUI.py to test this and test1.py and test2.py are the files which can be used to import GUI . 

GUI.py 

import logging 
from datetime import timedelta 
import time 
from thespian.actors import * 
from transitions import Machine 
import paho.mqtt.client as mqtt 
import importlib 
import os.path 
import sys 
from PyQt5.QtWidgets import * 
from PyQt5.QtCore import * 
from PyQt5 import QtWidgets, uic 
from mqtt import * 
import json 

class MainWindow(QtWidgets.QMainWindow): 
    def __init__(self,parent = None): 
        QMainWindow.__init__(self) 
        super(MainWindow, self).__init__(parent) 
        self.mdi = QMdiArea() 
        self.setCentralWidget(self.mdi) 

        self.setMinimumSize(QSize(800, 600)) 
        self.setWindowTitle("PyQt button example - pythonprogramminglanguage.com") 

        pybutton = QPushButton('Add device', self) 

        pybutton.clicked.connect(self.importbutton) 

        pybutton.move(100, 400) 
        pybutton.resize(150, 32) 

        self.textbox = QLineEdit(self) 
        self.textbox.move(100,350) 
        self.textbox.resize(100, 32) 
        
        self.fileName_UI = "" 

    def importbutton(self): 
        self.fileName_UI = self.textbox.text() 
        self.loadGUI() 

    def getGUIFilename(self): 
        return self.fileName_UI 

    def loadGUI(self): 
        print("Searching file", self.fileName_UI)       
        try: 
            module = __import__(self.fileName_UI) 
            my_class = getattr(module, "SubWindow") 

            sub = QMdiSubWindow() 

            sub.setWidget(my_class()) 
            sub.setWindowTitle("New GUI:  " + self.fileName_UI) 
            self.mdi.addSubWindow(sub) 
            sub.show() 

            print("creating new instance " + self.fileName_UI) 
            client = device("Device") 
            client.run() 

            client.loop_start()  # start the loop 
            device_message = self.fileName_UI 
            time.sleep(2) 
            print("Subscribing to topic", "microscope/light_sheet_microscope/UI") 
            client.subscribe("microscope/light_sheet_microscope/UI") 
            print("Publishing message to topic", "microscope/light_sheet_microscope/UI") 
            client.publish("microscope/light_sheet_microscope/UI", json.dumps({"type": "device", "payload":{"name": self.fileName_UI, "cmd": "adding device"}}, indent=2)) 
            time.sleep(1)  # wait 
            client.loop_stop()  # stop the loop 
            print("Device added" + "\n") 
            listofdevice = [] 
            listofdevice.append(self.fileName_UI) 
            print(listofdevice) 
        except: 
            print("creating new instance " + self.fileName_UI) 
            client = device("Device") 
            client.run() 

            client.loop_start()  # start the loop 
            device_message = self.fileName_UI 
            time.sleep(2) 
            print("Subscribing to topic", "microscope/light_sheet_microscope/UI") 
            client.subscribe("microscope/light_sheet_microscope/UI") 
            print("Publishing message to topic", "microscope/light_sheet_microscope/UI") 
            client.publish("microscope/light_sheet_microscope/UI", json.dumps({"type": "device", "payload":{"name": self.fileName_UI}}, indent=2)) 
            time.sleep(2)  # wait 
            client.loop_stop()  # stop the loop 
            print(device_message + ".py " + "file doesn't exist") 
            print("Device not added") 
if __name__ == "__main__": 
    app = QApplication(sys.argv) 
    mainWin = MainWindow() 
    mainWin.show() 
    publishedMessage = mainWin.getGUIFilename() 
    sys.exit(app.exec_()) 

MQTT.py 
import logging 
from datetime import timedelta 
import time 
from thespian.actors import * 
from transitions import Machine 
import paho.mqtt.client as mqtt 
import importlib 
import os.path 
import sys 
from PyQt5.QtWidgets import * 
from PyQt5.QtCore import * 
from PyQt5 import QtWidgets, uic 

class device(mqtt.Client): 
    def on_connect(self, mqttc, obj, flags, rc): 
        if rc == 0: 
            print("Connected to broker") 
        else: 
            print("Connection failed") 

        # mqttc.subscribe("microscope/light_sheet_microscope/UI") 

    def on_message(self, mqttc, userdata, message): 
        msg = str(message.payload.decode("utf-8")) 
        print("message recieved= " + msg) 
        # print("File which you want to import(with .py extension)") 
        print("message topic=", message.topic) 
        print("message qos=", message.qos) 
        print("message retain flag=", message.retain) 

    def run(self): 
        self.connect("broker.hivemq.com", 1883, 60) 

test1.py

from PyQt5 import QtCore, QtGui, QtWidgets
import sys
from PyQt5.QtWidgets import *
from PyQt5.QtCore import *
from PyQt5 import QtWidgets, uic
from mqtt import *

class SubWindow(QWidget):
    def __init__(self, parent = None):
        super(SubWindow, self).__init__(parent)
        self.setMinimumSize(QSize(300, 200))
        label = QLabel("Laser",  self)
        
        self.modeButton = QtWidgets.QPushButton("Click me",self)
        self.modeButton.setGeometry(QtCore.QRect(10, 40, 81, 23))
        self.modeButton.setObjectName("Turn on")
        self.modeButton.clicked.connect(self.modFun)

    def modFun(self):
            print("creating new instance " + "Laser")
            client = device("Laser")
            client.run()

            client.loop_start()  # start the loop
            device_message = "ON"
            time.sleep(2)
            print("Subscribing to topic", "microscope/light_sheet_microscope/UI")
            client.subscribe("microscope/light_sheet_microscope/UI")
            print("Publishing message to topic", "microscope/light_sheet_microscope/UI")
            client.publish("microscope/light_sheet_microscope/UI", device_message)
            time.sleep(2)  # wait
            client.loop_stop()  # stop the loop
        
    def closeEvent(self, event):
        self.close()

test2.py

from PyQt5 import QtCore, QtGui, QtWidgets
import sys
from PyQt5.QtWidgets import *
from PyQt5.QtCore import *
from PyQt5 import QtWidgets, uic

class SubWindow(QWidget):
    def __init__(self, parent = None):
        super(SubWindow, self).__init__(parent)
        self.setMinimumSize(QSize(300, 250))
        label = QLabel("Sub Window",  self)
        
        self.modeButton = QtWidgets.QPushButton("Click me",self)
        self.modeButton.setGeometry(QtCore.QRect(10, 40, 81, 23))
        
        self.modeButton.clicked.connect(self.modFun)

        

    def modFun(self):
        print("Hello there i'm Click me")
        
    def closeEvent(self, event):
        self.close()

Thanks.