PyQt: How to get UI data from a QThread

Question

I have the following code but it's complaining that I cannot access the UI data from my thread. In my example code below, What is the best way I can access the userInputString value so my threading can run?

self.nameField is a PyQt QLineEdit.

QObject::setParent: Cannot set parent, new parent is in a different thread
QPixmap: It is not safe to use pixmaps outside the GUI thread
QWidget::repaint: Recursive repaint detected

import myUI

class MainUIClass(QtGui.QMainWindow, myUI.Ui_MainWindow):
    def __init__(self, parent=None):
        super(MainUIClass, self).__init__(parent)
        self.setupUi(self)

        self.startbutton.clicked.connect(self.do_work)

        self.workerThread = WorkerThread()
        self.connect(self.workerThread, SIGNAL("myThreading()"), self.myThreading, Qt.DirectConnection)

    def do_work(self):
        self.userInputString = self.nameField.Text()
        self.workerThread.start()

    def myThreading(self):

        if userInputString is not None:
            #Do something

class WorkerThread(QThread):
    def __init__(self, parent=None):
        super(WorkerThread, self).__init__(parent)

    def run(self):
        self.emit(SIGNAL("myThreading()"))

if __name__ == '__main__':
    a = QtGui.QApplication(sys.argv)
    app = MainUIClass()
    app.show()
    a.exec_()

Answer 1

Not sure if it's what you need but here is a working QThread exemple using Qt5

import time
import sys
from PyQt5 import QtWidgets, QtGui, QtCore

class MainWindow(QtWidgets.QMainWindow):
    def __init__(self, parent=None):
        super(MainWindow, self).__init__(parent)
        self.worker_thread = WorkerThread()
        self.worker_thread.job_done.connect(self.on_job_done)
        self.create_ui()

    def create_ui(self):
        self.button = QtWidgets.QPushButton('Test', self)
        self.button.clicked.connect(self.start_thread)
        layout = QtWidgets.QVBoxLayout(self)
        layout.addWidget(self.button)

    def start_thread(self):
        self.worker_thread.gui_text = self.button.text()
        self.worker_thread.start()

    def on_job_done(self, generated_str):
        print("Generated string : ", generated_str)
        self.button.setText(generated_str)


class WorkerThread(QtCore.QThread):

    job_done = QtCore.pyqtSignal('QString')

    def __init__(self, parent=None):
        super(WorkerThread, self).__init__(parent)
        self.gui_text = None

    def do_work(self):

        for i in range(0, 1000):
            print(self.gui_text)
            self.job_done.emit(self.gui_text + str(i))
            time.sleep(0.5)

    def run(self):
        self.do_work()


if __name__ == '__main__':
    app = QtWidgets.QApplication(sys.argv)
    test = MainWindow()
    test.show()
    app.exec_()