在 PyQt 脚本中使用多处理时的 RuntimeError 和 IOError

RuntimeError and IOError when using multiprocessing in a PyQt script

我正在尝试在 PyQt class 内的 for 循环中使用多处理模块。 不幸的是,这个脚本给了我很多错误。这是仅显示 "Run" 按钮并在循环中启动进程并打印值的脚本。

import multiprocessing
from PyQt4 import QtGui
import sys

class SurfViewer(QtGui.QMainWindow):
    def __init__(self, parent=None):
        super(SurfViewer, self).__init__()
        self.parent = parent
        self.centralWidget = QtGui.QWidget()
        self.setCentralWidget(self.centralWidget)
        self.mainHBOX_param_scene = QtGui.QHBoxLayout()
        self.Button_Run = QtGui.QPushButton('Run')
        self.mainHBOX_param_scene.addWidget(self.Button_Run)
        self.centralWidget.setLayout(self.mainHBOX_param_scene)

        self.Button_Run.clicked.connect(self.Runclick)

    def Runclick(self):
        for i in range(5):
            p = multiprocessing.Process(target=self.mp_worker,args=(i,))
            p.start()

    def mp_worker(self,a):
        print('a:' + str(a))
        return

def main():
    app = QtGui.QApplication(sys.argv)
    ex = SurfViewer(app)
    ex.show()
    sys.exit(app.exec_())

if __name__ == '__main__':
    main()

我不明白我做错了什么,因为下面的代码运行良好:

import multiprocessing

class maclass():
    def __init__(self,):
        for i in range(5):
            p = multiprocessing.Process(target=self.mp_worker , args=(i,))
            p.start()

    def mp_worker(self,a):
        print('a:' +str(a))
        return

def main():
    maclass()

if __name__ == '__main__':
    main()

唯一的区别是多进程是在 Button_Run.clicked. event 中完成的。

我得到的错误是(来自第一个脚本):

Traceback (most recent call last):

File "", line 1, in

File "C:\Anaconda2\lib\multiprocessing\forking.py", line 381, in main self = load(from_parent)

File "C:\Anaconda2\lib\pickle.py", line 1384, in load return Unpickler(file).load()

File "C:\Anaconda2\lib\pickle.py", line 864, in load dispatchkey

File "C:\Anaconda2\lib\pickle.py", line 1221, in load_build setstate = getattr(inst, "setstate", None)

RuntimeError: super-class init() of type QPushButton was never called

但是当我尝试在更大的应用程序中使用多进程时,我也会遇到其他错误,例如:

File "C:\Anaconda2\lib\pickle.py", line 492, in save_string

self.write(BINSTRING + pack(" i", n) + obj)

IOError: [Errno 32] Broken pipe

也许这个可以与第一个错误相关联。

有人已经看到该问题的解决方案了吗?

编辑: 我尝试使用下面的@ImportanceOfBeingErnest 示例。所以这是新代码:

import multiprocessing
from PyQt4 import QtGui
import sys

class maclass():
    def __init__(self,):
        pass

    def start(self, n):
        lfp=[]
        for i in range(n):
            recv_end, send_end = multiprocessing.Pipe()
            p = multiprocessing.Process(target=self.mp_worker , args=(i,send_end))
            p.start()
            send_end.close()
            lfp.append(recv_end.recv())
            recv_end.close()
            print(i, lfp)
         #p.join()

    def mp_worker(self,a,send_end):
        print('a:' +str(a))
        send_end.send(a)
        return

class SurfViewer(QtGui.QMainWindow):
    def __init__(self, parent=None):
        super(SurfViewer, self).__init__()
        self.parent = parent
        self.centralWidget = QtGui.QWidget()
        self.setCentralWidget(self.centralWidget)
        self.mainHBOX_param_scene = QtGui.QHBoxLayout()
        self.Button_Run = QtGui.QPushButton('Run')
        self.mainHBOX_param_scene.addWidget(self.Button_Run)
        self.centralWidget.setLayout(self.mainHBOX_param_scene)

        self.worker = maclass()
        self.Button_Run.clicked.connect(self.start)

    def start(self):
        for k in range(5):
            self.worker.start(4)

def main():
    app = QtGui.QApplication(sys.argv)
    ex = SurfViewer(app)
    ex.show()
    sys.exit(app.exec_())

if __name__ == '__main__':
    main()

在这种情况下,我想从 recv_end, send_end = multiprocessing.Pipe() 的工作人员那里收到结果。从我得到正确结果的意义上说,这段代码工作正常。不幸的是,我似乎失去了多处理能力。很明显我的管道有问题,但我不知道它是什么。

您需要将工作人员与 UI 分开。以下工作正常。如果你想修改 maclass 中的变量,你仍然可以从外部进行。

import multiprocessing
from PyQt4 import QtGui
import sys

class maclass():

    def __init__(self,):
        pass

    def start(self):
        for i in range(5):
            p = multiprocessing.Process(target=self.mp_worker , args=(i,))
            p.start()

    def mp_worker(self,a):
        print('a:' +str(a))
        return


class SurfViewer(QtGui.QMainWindow):
    def __init__(self, parent=None):
        super(SurfViewer, self).__init__()
        self.parent = parent
        self.centralWidget = QtGui.QWidget()
        self.setCentralWidget(self.centralWidget)
        self.mainHBOX_param_scene = QtGui.QHBoxLayout()
        self.Button_Run = QtGui.QPushButton('Run')
        self.mainHBOX_param_scene.addWidget(self.Button_Run)
        self.centralWidget.setLayout(self.mainHBOX_param_scene)

        self.worker = maclass()
        self.Button_Run.clicked.connect(self.start)

    def start(self):
        self.worker.start()


def main():
    app = QtGui.QApplication(sys.argv)
    ex = SurfViewer(app)
    ex.show()
    sys.exit(app.exec_())


if __name__ == '__main__':
    main()

我终于找到了解决问题的方法。 下面是执行多处理并处理来自多线程工作者的结果 return 的代码:

import multiprocessing
from PyQt4 import QtGui
import sys

class maclass():

    def __init__(self,):
        pass
    @classmethod
    def start(self, n):
        lfp=[]
        r=[]
        for i in range(n):
            # queue = multiprocessing.Queue()
            recv_end, send_end = multiprocessing.Pipe()
            p = multiprocessing.Process(target=self.mp_worker , args=(i,send_end))
            p.start()
            r.append(recv_end)
        for recv_end in r:
            lfp.append(recv_end.recv() )
            print(i, lfp) 
    @classmethod
    def mp_worker(self,a,send_end):
        print('a:' +str(a))
        send_end.send(a)
        return


class SurfViewer(QtGui.QMainWindow):
    def __init__(self, parent=None):
        super(SurfViewer, self).__init__()
        self.parent = parent
        self.centralWidget = QtGui.QWidget()
        self.setCentralWidget(self.centralWidget)
        self.mainHBOX_param_scene = QtGui.QHBoxLayout()
        self.Button_Run = QtGui.QPushButton('Run')
        self.mainHBOX_param_scene.addWidget(self.Button_Run)
        self.centralWidget.setLayout(self.mainHBOX_param_scene)

        self.worker = maclass()
        self.Button_Run.clicked.connect(self.start)

    def start(self):
        for k in range(5):
            self.worker.start(20)



def main():
    app = QtGui.QApplication(sys.argv)
   ex = SurfViewer(app)
    ex.show()
    sys.exit(app.exec_())


if __name__ == '__main__':
    main()

非常感谢帮助过我的人。