PyQt QThread：如何在同一個線程中的worker對象上運行一個函數？

Question

我只是無法弄清楚如何正確使用QThreads。 我有一個worker對象，這里有一個gui，它有兩個組合框：當用戶在comboWorkspace上選擇一個項目時，comboModel上的項目將加載。 發生的事情是，無論何時我從comboWorkspace中選擇它，它都會再次從worker中運行get_workspaces函數。 這可能是因為我一遍又一遍地調用QThread的“啟動”功能。 如果這里有很多錯誤，我很抱歉。 如果有人能夠讓我知道如何正確處理這個問題。 非常感謝！

* setupUi函數的完整代碼位於：pastebin.com/Y7dGbRLu

from PyQt5 import QtCore, QtGui, QtWidgets
import os
import time
from functools import partial
import copy

class anaplanWorker(QtCore.QObject):

    signal_workspacenames = QtCore.pyqtSignal(str)
    signal_modelnames = QtCore.pyqtSignal(str)
    finish_progressbar = QtCore.pyqtSignal()
    start_progressbar = QtCore.pyqtSignal()
    finish_workspace_thread = QtCore.pyqtSignal()
    finish_model_thread = QtCore.pyqtSignal()
    count_run = 0

    def __init__(self, parent=None):
         QtCore.QThread.__init__(self, parent)


    def get_workspaces(self):
        ws_names = ['Name One', 'Name Two', 'Name Three']

        self.start_progressbar.emit()
        for ws_name in ws_names:
            self.signal_workspacenames.emit(ws_name)

        self.finish_workspace_thread.emit()


    def get_models(self,workspaceindex):

        self.start_progressbar.emit()

        models = ['Model One', 'Model Two', 'Model Three']

        for model_name in models:
            self.signal_modelnames.emit(model_name)

        self.finish_model_thread.emit()


class Ui_MainWindow(object):
    def setupUi(self, MainWindow):
        """ui setup for combo combo boxes: comboWorkspace and comboModel"""

    def progress_start(self):
        print("start")

    def progress_finish(self):
        print("finish")

#workspace functions
    def add_workspace(self, workspace_name):
        self.comboWorkspace.addItem(workspace_name)

    def start_workspace(self):

        self.comboWorkspace.clear()
        self.workspace_thread = self.anaplan_thread
        self.anaplan_worker.moveToThread(self.workspace_thread)
        self.workspace_thread.started.connect(self.anaplan_worker.get_workspaces)        
        self.workspace_thread.start()

#model functions
    def add_model(self, model_name):
        self.comboModel.addItem(model_name)

    def start_model(self):
        #clear combomodel
        self.comboModel.clear()
        workspaceIndex = self.comboWorkspace.currentIndex()

        self.model_thread = self.anaplan_thread
        self.anaplan_worker.moveToThread(self.model_thread)

        self.model_thread.started.connect(partial(self.anaplan_worker.get_models, workspaceIndex))

        self.model_thread.start()

#quit threads
    def quit_model_thread(self):
        self.model_thread.quit()
        print("quit model thread")

    def quit_workspace_thread(self):
        self.workspace_thread.quit()
        print("quit workspace thread")


    def retranslateUi(self, MainWindow):
        _translate = QtCore.QCoreApplication.translate
        MainWindow.setWindowTitle(_translate("MainWindow", "Tool"))
        self.labelWorkspace.setText(_translate("MainWindow", "Workspace"))
        self.labelModel.setText(_translate("MainWindow", "Model"))

        self.anaplan_worker = anaplanWorker()
        self.anaplan_thread = QtCore.QThread()

        self.anaplan_worker.signal_workspacenames.connect(self.add_workspace)

        self.anaplan_worker.signal_modelnames.connect(self.add_model)

        self.anaplan_worker.finish_workspace_thread.connect(self.quit_workspace_thread)

        self.anaplan_worker.finish_model_thread.connect(self.quit_model_thread)

        self.comboWorkspace.activated[str].connect(self.start_model)


if __name__ == "__main__":
    import sys
    app = QtWidgets.QApplication(sys.argv)
    MainWindow = QtWidgets.QMainWindow()
    ui = Ui_MainWindow()
    ui.setupUi(MainWindow)
    MainWindow.show()
    ui.start_workspace()
    sys.exit(app.exec_())

Answer 1

您應該更多地分割代碼。 它會解決你的很多問題。

您有兩個主要問題：每次更改索引時，您都會再次設置信號/插槽連接（一個連接意味着一個呼叫）。 您正在為兩個不同的任務使用相同的線程。

您應該創建一個新類MainWindow並在其中移動您的業務邏輯。 您的Ui_MainWindow類應該只處理UI部分（窗口小部件，布局等）。

你的anaplanWorker有很多問題：它來自QObject但是調用了QThread.__init__ ，你用它來創建一個線程和一個對象工作者 。 直接使用QThread會更清楚。

該類應分為兩個不同的部分，一個用於工作區，一個用於模型：

class ModelWorker(QtCore.QObject):

    signal_modelnames = QtCore.pyqtSignal(str)
    finish_progressbar = QtCore.pyqtSignal()
    start_progressbar = QtCore.pyqtSignal()
    finish_model_thread = QtCore.pyqtSignal()

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

    def get_models(self,workspaceindex):
        print("Get models with", workspaceindex)
        self.start_progressbar.emit()

        models = ['Model One', 'Model Two', 'Model Three']

        for model_name in models:
            self.signal_modelnames.emit(model_name)

        self.finish_model_thread.emit()

class WorkspaceWorker(QtCore.QObject):
    signal_workspacenames = QtCore.pyqtSignal(str)
    finish_progressbar = QtCore.pyqtSignal()
    start_progressbar = QtCore.pyqtSignal()
    finish_workspace_thread = QtCore.pyqtSignal()
    finish_model_thread = QtCore.pyqtSignal()

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


    def get_workspaces(self):
        ws_names = ['Name One', 'Name Two', 'Name Three']

        self.start_progressbar.emit()
        for ws_name in ws_names:
            self.signal_workspacenames.emit(ws_name)

        self.finish_workspace_thread.emit()

然后，在MainWindow類中，創建並設置線程和連接。 您只需在需要時啟動該線程。

class MainWindow(QMainWindow, Ui_MainWindow):
    def __init__(self, parent=None):
        super().__init__(parent)

        self.setupUi(self)

        self.workspaceWorker = WorkspaceWorker()
        self.modelWorker = ModelWorker()

        self.workspaceWorker_thread = QThread(self)
        self.modelWorker_thread = QThread(self)

        self.workspaceWorker.moveToThread(self.workspaceWorker_thread)
        self.modelWorker.moveToThread(self.modelWorker_thread)

        self.workspaceWorker.signal_workspacenames.connect(self.add_workspace)
        self.workspaceWorker.finish_workspace_thread.connect(self.quit_workspace_thread)

        self.modelWorker.signal_modelnames.connect(self.add_model)
        self.modelWorker.finish_model_thread.connect(self.quit_model_thread)

        self.comboWorkspace.activated[str].connect(self.start_model)

        self.modelWorker_thread.started.connect(lambda: self.modelWorker.get_models(self.comboWorkspace.currentIndex()))
        self.workspaceWorker_thread.started.connect(self.workspaceWorker.get_workspaces)

        self.start_workspace()


    def add_workspace(self, workspace_name):
        self.comboWorkspace.addItem(workspace_name)

    def start_workspace(self):

        self.comboWorkspace.clear()
        self.workspaceWorker_thread.start()

#model functions
    def add_model(self, model_name):
        self.comboModel.addItem(model_name)

    def start_model(self):
        #clear combomodel
        self.comboModel.clear()
        self.modelWorker_thread.start()

#quit threads
    def quit_model_thread(self):
        self.modelWorker_thread.quit()
        print("quit model thread")

    def quit_workspace_thread(self):
        self.workspaceWorker_thread.quit()
        print("quit workspace thread")