PySide2 QThread Issue

pyqt5.py

import sys

from PyQt5.QtCore import QThread
from PyQt5.QtWidgets import (QApplication, QMainWindow, QPushButton,
                             QComboBox, QWidget, QVBoxLayout)


class Task(QThread):
    def run(self):
        print('task started')
        k = 0
        for i in range(10000):
            for j in range(50000):
                k += 1
        print('task finished')


class Gui(QMainWindow):
    def __init__(self):
        super().__init__()
        base = QWidget()
        layout = QVBoxLayout()
        button = QPushButton('click me')
        button.clicked.connect(self.do_task)
        combobox = QComboBox()
        combobox.addItems(['1', '2', '3', '4', '5'])
        layout.addWidget(button)
        layout.addWidget(combobox)
        base.setLayout(layout)
        self.setCentralWidget(base)

    def do_task(self):
        self.thread = Task()
        self.thread.start()


def main():
    app = QApplication(sys.argv)
    window = Gui()
    window.show()
    sys.exit(app.exec_())


if __name__ == '__main__':
    main()

pyqt5_mppool.py

import sys
import multiprocessing as mp

from PyQt5.QtCore import QThread
from PyQt5.QtWidgets import (QApplication, QMainWindow, QPushButton,
                             QComboBox, QWidget, QVBoxLayout)


class Task(QThread):
    def run(self):
        print('task started')
        with mp.Pool() as pool:
            res = pool.map(mp_task, range(10000))
        print('task finished')


def mp_task(x):
    ret = 0
    for i in range(x + 50000):
        ret += i
    return ret


class Gui(QMainWindow):
    def __init__(self):
        super().__init__()
        base = QWidget()
        layout = QVBoxLayout()
        button = QPushButton('click me')
        button.clicked.connect(self.do_task)
        combobox = QComboBox()
        combobox.addItems(['1', '2', '3', '4', '5'])
        layout.addWidget(button)
        layout.addWidget(combobox)
        base.setLayout(layout)
        self.setCentralWidget(base)

    def do_task(self):
        self.thread = Task()
        self.thread.start()


def main():
    app = QApplication(sys.argv)
    window = Gui()
    window.show()
    sys.exit(app.exec_())


if __name__ == '__main__':
    main()

pyside2.py

import sys

from PySide2.QtCore import QThread
from PySide2.QtWidgets import (QApplication, QMainWindow, QPushButton,
                               QComboBox, QWidget, QVBoxLayout)


class Task(QThread):
    def run(self):
        print('task started')
        k = 0
        for i in range(10000):
            for j in range(50000):
                k += 1
        print('task finished')


class Gui(QMainWindow):
    def __init__(self):
        super().__init__()
        base = QWidget()
        layout = QVBoxLayout()
        button = QPushButton('click me')
        button.clicked.connect(self.do_task)
        combobox = QComboBox()
        combobox.addItems(['1', '2', '3', '4', '5'])
        layout.addWidget(button)
        layout.addWidget(combobox)
        base.setLayout(layout)
        self.setCentralWidget(base)

    def do_task(self):
        self.thread = Task()
        self.thread.start()


def main():
    app = QApplication(sys.argv)
    window = Gui()
    window.show()
    sys.exit(app.exec_())


if __name__ == '__main__':
    main()

pyside2_mppool.py

import sys
import multiprocessing as mp

from PySide2.QtCore import QThread
from PySide2.QtWidgets import (QApplication, QMainWindow, QPushButton,
                               QComboBox, QWidget, QVBoxLayout)


class Task(QThread):
    def run(self):
        print('task started')
        with mp.Pool() as pool:
            res = pool.map(mp_task, range(10000))
        print('task finished')


def mp_task(x):
    ret = 0
    for i in range(x + 50000):
        ret += i
    return ret


class Gui(QMainWindow):
    def __init__(self):
        super().__init__()
        base = QWidget()
        layout = QVBoxLayout()
        button = QPushButton('click me')
        button.clicked.connect(self.do_task)
        combobox = QComboBox()
        combobox.addItems(['1', '2', '3', '4', '5'])
        layout.addWidget(button)
        layout.addWidget(combobox)
        base.setLayout(layout)
        self.setCentralWidget(base)

    def do_task(self):
        self.thread = Task()
        self.thread.start()


def main():
    app = QApplication(sys.argv)
    window = Gui()
    window.show()
    sys.exit(app.exec_())


if __name__ == '__main__':
    main()