我正在尝试学习如何在PyQt Gui应用程序中使用QThreads。我有一些可以运行一段时间的东西,(通常)可以在其中更新Gui的点,但是我想将主要工作拆分为自己的线程(有时东西会卡住,最终有一个取消/重试按钮,如果Gui被冻结(因为主循环被阻塞),则该按钮显然不起作用)。
我已阅读https://mayaposch.wordpress.com/2011/11/01/how-to-really-truly-use- qthreads-the-full- explanation/。该页面显示,重新实现该run方法不是实现该方法的方法。我遇到的问题是找到一个PyQt示例,该示例具有一个执行Gui的主线程和一个不执行此操作的工作线程。该博客文章适用于C ++,因此尽管它的示例确实有帮助,但我仍然有些失落。有人可以给我指出在Python中执行正确方法的示例吗?
run
这是一个单独的工作线程的工作示例,该工作线程可以发送和接收信号以使其与GUI通信。
我做了两个简单的按钮,一个按钮在一个单独的线程中开始长时间的计算,另一个按钮立即终止计算并重置工作线程。
通常,强行终止线程并不是执行此操作的最佳方法,但是在某些情况下,始终不能正常退出是不可行的。
from PyQt4 import QtGui, QtCore import sys import random class Example(QtCore.QObject): signalStatus = QtCore.pyqtSignal(str) def __init__(self, parent=None): super(self.__class__, self).__init__(parent) # Create a gui object. self.gui = Window() # Create a new worker thread. self.createWorkerThread() # Make any cross object connections. self._connectSignals() self.gui.show() def _connectSignals(self): self.gui.button_cancel.clicked.connect(self.forceWorkerReset) self.signalStatus.connect(self.gui.updateStatus) self.parent().aboutToQuit.connect(self.forceWorkerQuit) def createWorkerThread(self): # Setup the worker object and the worker_thread. self.worker = WorkerObject() self.worker_thread = QtCore.QThread() self.worker.moveToThread(self.worker_thread) self.worker_thread.start() # Connect any worker signals self.worker.signalStatus.connect(self.gui.updateStatus) self.gui.button_start.clicked.connect(self.worker.startWork) def forceWorkerReset(self): if self.worker_thread.isRunning(): print('Terminating thread.') self.worker_thread.terminate() print('Waiting for thread termination.') self.worker_thread.wait() self.signalStatus.emit('Idle.') print('building new working object.') self.createWorkerThread() def forceWorkerQuit(self): if self.worker_thread.isRunning(): self.worker_thread.terminate() self.worker_thread.wait() class WorkerObject(QtCore.QObject): signalStatus = QtCore.pyqtSignal(str) def __init__(self, parent=None): super(self.__class__, self).__init__(parent) @QtCore.pyqtSlot() def startWork(self): for ii in range(7): number = random.randint(0,5000**ii) self.signalStatus.emit('Iteration: {}, Factoring: {}'.format(ii, number)) factors = self.primeFactors(number) print('Number: ', number, 'Factors: ', factors) self.signalStatus.emit('Idle.') def primeFactors(self, n): i = 2 factors = [] while i * i <= n: if n % i: i += 1 else: n //= i factors.append(i) if n > 1: factors.append(n) return factors class Window(QtGui.QWidget): def __init__(self): QtGui.QWidget.__init__(self) self.button_start = QtGui.QPushButton('Start', self) self.button_cancel = QtGui.QPushButton('Cancel', self) self.label_status = QtGui.QLabel('', self) layout = QtGui.QVBoxLayout(self) layout.addWidget(self.button_start) layout.addWidget(self.button_cancel) layout.addWidget(self.label_status) self.setFixedSize(400, 200) @QtCore.pyqtSlot(str) def updateStatus(self, status): self.label_status.setText(status) if __name__=='__main__': app = QtGui.QApplication(sys.argv) example = Example(app) sys.exit(app.exec_())