import sys
import time
from PyQt5 import QtWidgets
from PyQt5.QtCore import QThread, pyqtSignal
from mydialog import Ui_mydialog


class Mainwindow(QtWidgets.QMainWindow, Ui_mydialog):

    def __init__(self, *args, obj=None, **kwargs):
        super(Mainwindow, self).__init__(*args, **kwargs)
        self.setupUi(self)

        self.thread = Worker()
        self.loop = loop()
        self.thread.sig.connect(self.updatelabel)

        self.mypushbutton.clicked.connect(self.mypushbuttonclicked)


    def mypushbuttonclicked(self):
        self.thread.start()

    def updatelabel(self, text):
        self.mylabel.setText(text)

class Worker(QThread):

    sig = pyqtSignal(str)

    def __init__(self, parent=None):
        super(Worker, self).__init__(parent)
        # self.count = 0
        self.loop = loop()

    def run(self):

        self.loop.methodA()

        ## Original code without being in class loop and method loopA
        # while True:
        #     time.sleep(1)
        #     self.count += 1
        #     if (self.count % 1 == 0):
        #         self.sig.emit(f"Timer: {self.count} s")

# Newly added class with method "methodA"
class loop(object):

    sig = pyqtSignal(str)

    def __init__(self):
        self.count = 0

    def methodA(self):

        while True:
            time.sleep(1)
            self.count += 1
            if (self.count % 1 == 0):
                self.sig.emit(f"Timer: {self.count} s")



app = QtWidgets.QApplication(sys.argv)
window = Mainwindow()
app.setStyle("Fusion")
window.show()
app.exec()