code crash after opening a QfileDialog in a QThread

问题

I wrote a code who display in a GUI, the steps of calcul of an algorithm. For this, i use a QThread which is in charge to check the steps and display it in a GUI. This alone is working. However, the first step for the user is to select a configuration file with a QFileDialog. And at this level, Python code crashes after the openning of the QFileDialog if a file is not selected after several seconds. The crash occures when the mouse goes over the QFileDialog window openned. I quite new with the use of QThread. I started with this post Background thread with QThread in PyQt. If someone could help me understand where is my error, that would be great! Thanks!

# main_thread_simple.py
from PyQt5.QtCore import QThread
from PyQt5.QtWidgets import QApplication, QLabel, QWidget, QGridLayout, QFileDialog
import sys
import worker_simple
import os

#https://stackoverflow.com/questions/6783194/background-thread-with-qthread-in-pyqt/6789205

class Form(QWidget):

    def __init__(self):
       super(Form,self).__init__()
       self.label1 = QLabel("")
       self.label2 = QLabel("") 
       self.label3 = QLabel("") 
       self.label4 = QLabel("") 
       self.label5 = QLabel("") 
       self.label6 = QLabel("") 
       self.label7 = QLabel("") 
       self.label8 = QLabel("") 
       self.label9 = QLabel("") 
       self.label10 = QLabel("") 
       self.label11 = QLabel("") 

       fileName, _ = QFileDialog.getOpenFileName(self,"Sélectionner le fichier de configuration", filter = "(*.xlsx)")
       repertoire_fichier_configuration = os.path.basename(fileName)


       self.obj = worker_simple.Worker(repertoire_fichier_configuration)  # no parent!
       self.thread = QThread()  # no parent!

       # 2 - Connect Worker`s Signals to Form method slots to post data.
       self.obj.strReady1.connect(self.onStrReady1)
       self.obj.strReady2.connect(self.onStrReady2)

       # 3 - Move the Worker object to the Thread object
       self.obj.moveToThread(self.thread)

       # 4 - Connect Worker Signals to the Thread slots
       self.obj.finished.connect(self.thread.quit)

       # 5 - Connect Thread started signal to Worker operational slot method
       self.thread.started.connect(self.obj.Main)

       # * - Thread finished signal will close the app if you want!
#       self.thread.finished.connect(app.exit)

       # 6 - Start the thread
       self.thread.start()

       # 7 - Start the form
       self.initUI()


    def initUI(self):
        grid = QGridLayout()
        self.setLayout(grid)
        grid.addWidget(self.label1,0,0)
        grid.addWidget(self.label2,1,0)

        self.move(300, 150)
        self.setWindowTitle('outil de calcul')
        self.show()

    def onStrReady1(self, txt):
        self.label1.setText("{}".format(txt))
    def onStrReady2(self, txt):
        self.label2.setText("{}".format(txt))


app = QApplication(sys.argv)
form = Form()
sys.exit(app.exec_())
del app


# worker.py
from PyQt5.QtCore import QObject, pyqtSignal, pyqtSlot
import os
from PyQt5.QtWidgets import QFileDialog

class Worker(QObject):

    finished = pyqtSignal()
    strReady1 = pyqtSignal(str)
    strReady2 = pyqtSignal(str)

    def __init__(self, fichier_config, parent = None):
        super(Worker, self).__init__(parent)

        self.fichier_config = fichier_config

    @pyqtSlot()
    def Main(self): # A slot takes no params

        nom_fichier_configuration = self.fichier_config

        self.strReady1.emit('début des calculs')

        '''         code qui s'execute + appel à une fonction qui prend comme paramètre 'nom_fichier_configuration'  '''

        self.strReady2.emit('fin des calculs')    

        self.finished.emit()

来源：https://stackoverflow.com/questions/57693276/code-crash-after-opening-a-qfiledialog-in-a-qthread