PyQt5 QThread 问题

Question

我正在尝试了解 QT5 线程的基础知识。这是我的第一次尝试，结合了各种来源：

import sys
from time import sleep

from PyQt5.QtWidgets import QApplication, QWidget, QPushButton, QGridLayout

from PyQt5.QtCore import QThread, QObject


'''

Traceback (most recent call last):
  File "threads.py", line 68, in <module>
    main(sys.argv)
  File "threads.py", line 63, in main
    window = Window()
  File "threads.py", line 15, in __init__
    self.initUi()
  File "threads.py", line 28, in initUi
    self.worker.moveToThread(self.thread)
AttributeError: 'NoneType' object has no attribute 'moveToThread'
Press any key to continue . . .

'''



class Window(QWidget):

    def __init__(self):

        super().__init__()
        self.initUi()

        self.low = 0
        self.high = 100

        self.show()


    def initUi(self):


        self.thread = QThread()
        self.worker = Worker(self)
        self.worker.moveToThread(self.thread)
        self.thread.start()

        self.button = QPushButton(
                'Start long running task')

        self.layout = QGridLayout()        
        self.layout.addWidget(self.button, 0, 0)

        self.setLayout(self.layout)



def Worker(QObject):

    def __init__(self, parent):
        super(Worker, self).__init__(parent)
        do_work()

    def do_work(self):

        for _ in range(20):
            print('running . . .')
            sleep(2)



def main(args):

    app = QApplication(args)
    window = Window()
    sys.exit(app.exec_())


if __name__ == '__main__':
    main(sys.argv)

我在代码 sn-p 中包含了我遇到的错误。 从在线文章中我了解到，在 PyQt5 中我不应该继承 QThread。

Answer 1

你有两个问题，第一个是worker必须是一个类才能改变：

def Worker(QObject):

到

class Worker(QObject):

另一个问题是你必须通过实例调用do_work，即self，因为它发生了变化：

do_work()

到：

self.do_work()

下面我展示一个完整的例子：

import sys

from PyQt5.QtWidgets import QApplication, QWidget, QPushButton, QGridLayout

from PyQt5.QtCore import QThread, QObject


class Window(QWidget):

    def __init__(self):

        super().__init__()
        self.initUi()

        self.low = 0
        self.high = 100

        self.show()


    def initUi(self):


        self.thread = QThread()
        self.worker = Worker()
        self.worker.moveToThread(self.thread)

        self.thread.started.connect(self.worker.do_work)
        self.thread.finished.connect(self.thread.deleteLater)

        self.button = QPushButton(
                'Start long running task')

        self.button.clicked.connect(self.thread.start)

        self.layout = QGridLayout()        
        self.layout.addWidget(self.button, 0, 0)
        self.setLayout(self.layout)



class Worker(QObject):
    def __init__(self, parent=None):
        QObject.__init__(self, parent=parent)

    def do_work(self):
        for _ in range(20):
            print('running . . .')
            QThread.sleep(2)



def main(args):

    app = QApplication(args)
    window = Window()
    window.show()
    sys.exit(app.exec_())


if __name__ == '__main__':
    main(sys.argv)