Python GUI with PyQt5 Multi Threading

Question

I'm trying to make my app support multi threading in connection with GUI , I'm trying to connect to method inside GUI from threading outside GUI, I have inspired this idea from Simplest way for PyQT Threading and it was marked as working solution , where is my fault

Below is the error.

class Communicate(QtCore.QObject):
    myGUI_signal = QtCore.pyqtSignal(str)

def myThread(callbackFunc):
# Setup the signal-slot mechanism.
    mySrc = Communicate()
    mySrc.myGUI_signal.connect(callbackFunc)

# Endless loop. You typically want the thread
# to run forever.
    while(True):
    # Do something useful here.
        msgForGui = 'This is a message to send to the GUI'
        mySrc.myGUI_signal.emit(msgForGui)


FORM_CLASS, _ = loadUiType(os.path.join(os.path.dirname('__file__'), "main.ui"))

class MainApp(QMainWindow, FORM_CLASS):  # QMainWindow refere to window type used in ui file
# this is constructor
    def __init__(self, parent=None):
        super(MainApp, self).__init__(parent)
        QMainWindow.__init__(self)
        self.setupUi(self)
        self.ui()
        self.actions()

    def ui(self):
        self.setFixedSize(848, 663)
    
    def actions(self):
        self.pushButton.clicked.connect(self.startTheThread)

    def theCallbackFunc(self, msg):
        print('the thread has sent this message to the GUI:')
        print(msg)
        print('---------')

    def startTheThread(self):
    # Create the new thread. The target function is 'myThread'. The
    # function we created in the beginning.
        t = threading.Thread(name = 'myThread', target = myThread, args =(self.theCallbackFunc))
        t.start()

def main():
    app = QApplication(sys.argv)
    window = MainApp()  # calling class of main window (first window)
    window.show()  # to show window
    app.exec_()  # infinit loop to make continous show for window

if __name__ == '__main__':
    main()

This is not fully related to the question, but you should consider using QThread when you deal with Qt, it will avoid you further issue in future, such as GUI which freeze... — Yohboy, Feb 27 '18 at 10:37

score 0 · Accepted Answer · answered Feb 27 '18 at 20:52

0

When instantiating the Python thread, args must be a tuple or list (or other iterable). args =(self.theCallbackFunc) is not a tuple. args =(self.theCallbackFunc,) is a tuple (note the extra comma needed for tuples containing a single value).

answered Feb 27 '18 at 20:52

three_pineapples

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Python GUI with PyQt5 Multi Threading

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