python - QObject::setParent:无法设置父级，新父级位于Python中的不同线程中-6ren

python - QObject::setParent:无法设置父级，新父级位于Python中的不同线程中

转载作者：行者123 更新时间：2023-12-01 08:10:57

我使用 PyQt5 开发的 GUI 遇到问题。

应用尝试从不同的线程更新窗口进度条的值(QThreadPool())。当它尝试更新进度条时，Python 会发出如下警告:

QObject::setParent: Cannot set parent, new parent is in a different thread

这在一定程度上不会影响应用程序，但一段时间后应用程序会崩溃并显示以下错误消息。

QBackingStore::endPaint() called with active painter on backingstore paint device

有人可以帮我摆脱第一个警告吗？我想这会解决问题。

我将发布代码的最小示例。

main.py

import sys
from PyQt5.QtCore import *
from PyQt5 import QtCore, QtGui, QtWidgets
import thread_for_audio_record
import time


class FW(object):
    def __init__(self):
        self.threadpool = QThreadPool()

    def f_w(self, window):
        self.window = window
        self.window.setObjectName("Test")
        self.window.resize(1054, 700)
        self.window.setStyleSheet("background-color: rgb(180, 180, 180);")
        self.central_widget = QtWidgets.QWidget(self.window)
        self.central_widget.setObjectName("centralwidget")
        self.horizontal_layout = QtWidgets.QHBoxLayout(self.central_widget)
        self.horizontal_layout.setObjectName("horizontalLayout")
        spacer_item = QtWidgets.QSpacerItem(129, 20, QtWidgets.QSizePolicy.Expanding, QtWidgets.QSizePolicy.Minimum)
        self.horizontal_layout.addItem(spacer_item)
        self.vertical_layout = QtWidgets.QVBoxLayout()
        self.vertical_layout.setObjectName("verticalLayout")
        spacer_item_1 = QtWidgets.QSpacerItem(128, 13, QtWidgets.QSizePolicy.Minimum, QtWidgets.QSizePolicy.Expanding)
        self.vertical_layout.addItem(spacer_item_1)
        self.label_utterance = QtWidgets.QLabel(self.central_widget)
        font = QtGui.QFont()
        font.setPointSize(15)
        font.setBold(True)
        font.setBold(True)
        font.setWeight(75)
        self.label_utterance.setFont(font)
        self.label_utterance.setAlignment(QtCore.Qt.AlignCenter)
        self.label_utterance.setObjectName("label_utterance")
        self.vertical_layout.addWidget(self.label_utterance)
        self.text_edit_utterance = QtWidgets.QTextEdit(self.central_widget)
        self.text_edit_utterance.setStyleSheet("background-color: rgb(255, 255, 255);")
        self.text_edit_utterance.setObjectName("text_edit_utterance")
        self.text_edit_utterance.setReadOnly(True)
        self.text_edit_utterance.setFont(font)
        self.vertical_layout.addWidget(self.text_edit_utterance)
        self.line_edit_message_for_user = QtWidgets.QLineEdit(self.central_widget)
        self.line_edit_message_for_user.setStyleSheet("background-color: rgb(255, 255, 255);")
        self.line_edit_message_for_user.setObjectName("lineEdit")
        self.progressBar = QtWidgets.QProgressBar(self.central_widget)
        self.progressBar.setProperty("value", 0)
        self.progressBar.setObjectName("progressBar")
        self.vertical_layout.addWidget(self.progressBar)
        self.vertical_layout.addWidget(self.line_edit_message_for_user)
        self.push_button_start_recording = QtWidgets.QPushButton(self.central_widget)
        font = QtGui.QFont()
        font.setBold(True)
        font.setWeight(75)
        self.push_button_start_recording.setFont(font)
        self.push_button_start_recording.setStyleSheet("background-color: rgb(85, 170, 0);")
        self.push_button_start_recording.setObjectName("pushButton_start_
                                                           recording")

        self.push_button_start_recording.clicked.connect(self.start_button_
                                                               func)
        self.vertical_layout.addWidget(self.push_button_start_recording)
        self.push_button_end_recording = QtWidgets.QPushButton(self.central_widget)
        font = QtGui.QFont()
        font.setBold(True)
        font.setWeight(75)
        self.push_button_end_recording.setFont(font)
        self.push_button_end_recording.setStyleSheet("background-color: rgb(182, 0, 0);")
        self.push_button_end_recording.setObjectName("pushButton_end_
                                                        recording")
        self.vertical_layout.addWidget(self.push_button_end_recording)
        self.label_status = QtWidgets.QLabel(self.central_widget)
        font = QtGui.QFont()
        font.setBold(True)
        font.setWeight(75)
        self.label_status.setFont(font)
        self.label_status.setObjectName("label_status")
        self.vertical_layout.addWidget(self.label_status)
        self.text_edit_status = QtWidgets.QTextEdit(self.central_widget)
        self.text_edit_status.setStyleSheet("background-color: rgb(255, 255, 255);")
        self.text_edit_status.setObjectName("textEdit_status")
        self.text_edit_status.setReadOnly(True)
        self.vertical_layout.addWidget(self.text_edit_status)
        self.push_button_record_again = QtWidgets.QPushButton(self.central_widget)
        font = QtGui.QFont()
        font.setBold(True)
        font.setWeight(75)
        self.push_button_record_again.setFont(font)
        self.push_button_record_again.setStyleSheet("background-color: rgb(255, 255, 127);")
        self.push_button_record_again.setObjectName("pushButton_record_
                                                               again")
        self.vertical_layout.addWidget(self.push_button_record_again)
        self.push_button_next_utterance = QtWidgets.QPushButton(self.central_widget)
        font = QtGui.QFont()
        font.setBold(True)
        font.setWeight(75)
        self.push_button_next_utterance.setFont(font)
        self.push_button_next_utterance.setStyleSheet("background-color: rgb(85, 170, 0);")
        self.push_button_next_utterance.setObjectName("pushButton_next_
                                                         utterance")
        self.vertical_layout.addWidget(self.push_button_next_utterance)
        spacer_item_2 = QtWidgets.QSpacerItem(128, 13, QtWidgets.QSizePolicy.Minimum, QtWidgets.QSizePolicy.Expanding)
        self.vertical_layout.addItem(spacer_item_2)
        self.horizontal_layout.addLayout(self.vertical_layout)
        spacer_item_3 = QtWidgets.QSpacerItem(128, 20, QtWidgets.QSizePolicy.Expanding, QtWidgets.QSizePolicy.Minimum)
        self.horizontal_layout.addItem(spacer_item_3)
        self.window.setCentralWidget(self.central_widget)
        self.menubar = QtWidgets.QMenuBar(self.window)
        self.menubar.setGeometry(QtCore.QRect(0, 0, 1054, 21))
        self.menubar.setObjectName("menubar")
        self.window.setMenuBar(self.menubar)
        self.statusbar = QtWidgets.QStatusBar(self.window)
        self.statusbar.setObjectName("statusbar")
        self.window.setStatusBar(self.statusbar)
        self.retranslate_ui(self.window)
        QtCore.QMetaObject.connectSlotsByName(self.window)

    def retranslate_ui(self, window):

        _translate = QtCore.QCoreApplication.translate
        window.setWindowTitle(_translate("Utterance Recording", "Test"))
        self.label_utterance.setText(_translate("Utterance Recording", "Test"))
        self.line_edit_message_for_user.setText(_translate("Utterance Recording", "Test."))
        self.text_edit_utterance.setText(_translate("utterance_parsing", ('Test')))
        self.push_button_start_recording.setText(_translate("Utterance Recording", "Start Recording"))
        self.push_button_end_recording.setText(_translate("Utterance Recording", "End Recording"))
        self.label_status.setText(_translate("Utterance Recording", "Test"))
        self.push_button_record_again.setText(_translate("Utterance Recording", "Test"))
        self.push_button_next_utterance.setText(_translate("Utterance Recording", "Test"))

    def inside_thread(self):
        percentage = 0
        while percentage < 120:
            percentage = percentage + 20
            time.sleep(0.2)
            self.progressBar.setValue(percentage)

    def start_button_func(self):
        self.worker = thread_for_audio_record.Worker(self.inside_thread)
        self.threadpool.start(self.worker)


if __name__ == "__main__":
    app = QtWidgets.QApplication(sys.argv)
    utterance_parsing_window = QtWidgets.QMainWindow()
    utterance_parsing = FW()
    utterance_parsing.f_w(utterance_parsing_window)
    utterance_parsing_window.show()
    sys.exit(app.exec_())

thread_for_audio_record.py

import os
from PyQt5.QtCore import *


class Worker(QRunnable):

    def __init__(self, fn):
        super(Worker, self).__init__()
        self.fn = fn
        self.originating_PID = os.getpid()
        self._running = True

    @pyqtSlot()
    def run(self):
        self.fn()

单击开始录制按钮，您将看到进度条正在更新。但给出警告消息是因为更新来自不同的线程。

最佳答案

首先，不要按照 PyQt 的建议修改 Qt Designer 生成的代码，而是创建另一个从适当的小部件继承的类，并使用初始类作为接口(interface)。

言归正传，Qt 不允许直接从另一个线程更新 GUI，在您的情况下，在辅助线程中调用 QProgressBar 的 setValue 导致在 secuandario 线程中进行绘制，因此 Qt 提示说它不能保证操作(例如，在您的情况下，它显然不会产生问题，但 Qt 不保证这种情况总是发生)。来自其他线程的 GUI 更新必须是间接的，可以通过信号、QEvent、QMetaObject::invokeMethod 等。在本例中我将使用信号:

import sys
from PyQt5 import QtCore, QtGui, QtWidgets
import thread_for_audio_record
import time


class FW(object):
    def f_w(self, window):
        self.window = window
        self.window.setObjectName("Test")
        self.window.resize(1054, 700)
        self.window.setStyleSheet("background-color: rgb(180, 180, 180);")
        self.central_widget = QtWidgets.QWidget(self.window)
        self.central_widget.setObjectName("centralwidget")
        self.horizontal_layout = QtWidgets.QHBoxLayout(self.central_widget)
        self.horizontal_layout.setObjectName("horizontalLayout")
        spacer_item = QtWidgets.QSpacerItem(129, 20, QtWidgets.QSizePolicy.Expanding, QtWidgets.QSizePolicy.Minimum)
        self.horizontal_layout.addItem(spacer_item)
        self.vertical_layout = QtWidgets.QVBoxLayout()
        self.vertical_layout.setObjectName("verticalLayout")
        spacer_item_1 = QtWidgets.QSpacerItem(128, 13, QtWidgets.QSizePolicy.Minimum, QtWidgets.QSizePolicy.Expanding)
        self.vertical_layout.addItem(spacer_item_1)
        self.label_utterance = QtWidgets.QLabel(self.central_widget)
        font = QtGui.QFont()
        font.setPointSize(15)
        font.setBold(True)
        font.setBold(True)
        font.setWeight(75)
        self.label_utterance.setFont(font)
        self.label_utterance.setAlignment(QtCore.Qt.AlignCenter)
        self.label_utterance.setObjectName("label_utterance")
        self.vertical_layout.addWidget(self.label_utterance)
        self.text_edit_utterance = QtWidgets.QTextEdit(self.central_widget)
        self.text_edit_utterance.setStyleSheet("background-color: rgb(255, 255, 255);")
        self.text_edit_utterance.setObjectName("text_edit_utterance")
        self.text_edit_utterance.setReadOnly(True)
        self.text_edit_utterance.setFont(font)
        self.vertical_layout.addWidget(self.text_edit_utterance)
        self.line_edit_message_for_user = QtWidgets.QLineEdit(self.central_widget)
        self.line_edit_message_for_user.setStyleSheet("background-color: rgb(255, 255, 255);")
        self.line_edit_message_for_user.setObjectName("lineEdit")
        self.progressBar = QtWidgets.QProgressBar(self.central_widget)
        self.progressBar.setProperty("value", 0)
        self.progressBar.setObjectName("progressBar")
        self.vertical_layout.addWidget(self.progressBar)
        self.vertical_layout.addWidget(self.line_edit_message_for_user)
        self.push_button_start_recording = QtWidgets.QPushButton(self.central_widget)
        font = QtGui.QFont()
        font.setBold(True)
        font.setWeight(75)
        self.push_button_start_recording.setFont(font)
        self.push_button_start_recording.setStyleSheet("background-color: rgb(85, 170, 0);")
        self.push_button_start_recording.setObjectName("pushButton_start_ recording")
        self.vertical_layout.addWidget(self.push_button_start_recording)
        self.push_button_end_recording = QtWidgets.QPushButton(self.central_widget)
        font = QtGui.QFont()
        font.setBold(True)
        font.setWeight(75)
        self.push_button_end_recording.setFont(font)
        self.push_button_end_recording.setStyleSheet("background-color: rgb(182, 0, 0);")
        self.push_button_end_recording.setObjectName("pushButton_end_recording")
        self.vertical_layout.addWidget(self.push_button_end_recording)
        self.label_status = QtWidgets.QLabel(self.central_widget)
        font = QtGui.QFont()
        font.setBold(True)
        font.setWeight(75)
        self.label_status.setFont(font)
        self.label_status.setObjectName("label_status")
        self.vertical_layout.addWidget(self.label_status)
        self.text_edit_status = QtWidgets.QTextEdit(self.central_widget)
        self.text_edit_status.setStyleSheet("background-color: rgb(255, 255, 255);")
        self.text_edit_status.setObjectName("textEdit_status")
        self.text_edit_status.setReadOnly(True)
        self.vertical_layout.addWidget(self.text_edit_status)
        self.push_button_record_again = QtWidgets.QPushButton(self.central_widget)
        font = QtGui.QFont()
        font.setBold(True)
        font.setWeight(75)
        self.push_button_record_again.setFont(font)
        self.push_button_record_again.setStyleSheet("background-color: rgb(255, 255, 127);")
        self.push_button_record_again.setObjectName("pushButton_record_again")
        self.vertical_layout.addWidget(self.push_button_record_again)
        self.push_button_next_utterance = QtWidgets.QPushButton(self.central_widget)
        font = QtGui.QFont()
        font.setBold(True)
        font.setWeight(75)
        self.push_button_next_utterance.setFont(font)
        self.push_button_next_utterance.setStyleSheet("background-color: rgb(85, 170, 0);")
        self.push_button_next_utterance.setObjectName("pushButton_next_utterance")
        self.vertical_layout.addWidget(self.push_button_next_utterance)
        spacer_item_2 = QtWidgets.QSpacerItem(128, 13, QtWidgets.QSizePolicy.Minimum, QtWidgets.QSizePolicy.Expanding)
        self.vertical_layout.addItem(spacer_item_2)
        self.horizontal_layout.addLayout(self.vertical_layout)
        spacer_item_3 = QtWidgets.QSpacerItem(128, 20, QtWidgets.QSizePolicy.Expanding, QtWidgets.QSizePolicy.Minimum)
        self.horizontal_layout.addItem(spacer_item_3)
        self.window.setCentralWidget(self.central_widget)
        self.menubar = QtWidgets.QMenuBar(self.window)
        self.menubar.setGeometry(QtCore.QRect(0, 0, 1054, 21))
        self.menubar.setObjectName("menubar")
        self.window.setMenuBar(self.menubar)
        self.statusbar = QtWidgets.QStatusBar(self.window)
        self.statusbar.setObjectName("statusbar")
        self.window.setStatusBar(self.statusbar)
        self.retranslate_ui(self.window)
        QtCore.QMetaObject.connectSlotsByName(self.window)

    def retranslate_ui(self, window):

        _translate = QtCore.QCoreApplication.translate
        window.setWindowTitle(_translate("Utterance Recording", "Altran Audio Manager"))
        self.label_utterance.setText(_translate("Utterance Recording", "Test"))
        self.line_edit_message_for_user.setText(_translate("Utterance Recording", "Test."))
        self.text_edit_utterance.setText(_translate("utterance_parsing", ('Test')))
        self.push_button_start_recording.setText(_translate("Utterance Recording", "Start Recording"))
        self.push_button_end_recording.setText(_translate("Utterance Recording", "End Recording"))
        self.label_status.setText(_translate("Utterance Recording", "Test"))
        self.push_button_record_again.setText(_translate("Utterance Recording", "Test"))
        self.push_button_next_utterance.setText(_translate("Utterance Recording", "Test"))


class MainWindow(QtWidgets.QMainWindow, FW):
    progressChanged = QtCore.pyqtSignal(int)

    def __init__(self, parent=None):
        super(MainWindow, self).__init__(parent)
        self.threadpool = QtCore.QThreadPool()
        self.f_w(self)
        self.push_button_start_recording.clicked.connect(self.start_button_func)
        self.progressChanged.connect(self.progressBar.setValue)

    def inside_thread(self):
        percentage = 0
        while percentage < 120:
            percentage = percentage + 20
            time.sleep(0.2)
            self.progressChanged.emit(percentage)

    def start_button_func(self):
        self.worker = thread_for_audio_record.Worker(self.inside_thread)
        self.threadpool.start(self.worker)


if __name__ == "__main__":
    app = QtWidgets.QApplication(sys.argv)
    w = MainWindow()
    w.show()
    sys.exit(app.exec_())

关于python - QObject::setParent:无法设置父级，新父级位于Python中的不同线程中，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/55257343/

文章推荐： asp.net-mvc - Devexpress Grid MVC 3 Razor 引擎

文章推荐： jQuery 移动 : login link goes to last cached page

文章推荐： oracle - 从批处理文件执行 SQL

c++ - 错误 `QObject` 子类和复制构造函数 : `QObject::QObject(const QObject&) is private`
以下是我遇到的编译错误: /usr/lib/qt-3.3/include/qobject.h: In copy constructor Product::Product(const Product&)
c++ - 'QObject::QObject' 无法访问在类 'QObject' 中声明的私有(private)成员
class CHIProjectData : public QObject { public: CHIProjectData(); CHIProjectData(QMap aProje
c++ - 'QObject::QObject(const QObject&)' 是私有(private)的
这个问题在这里已经有了答案: Could I have copy constructor for subclass of QObject? (3 个答案) 关闭 7 年前。我收到错误: C:\Qt
c++ - 'QObject& QObject::operator=(const QObject&)' 是私有(private)的
将一个项目从 Qt4 迁移到 Qt5 我得到了这个错误，我已经研究过，显然你不能从 QObject 创建一个派生类的复制构造函数(这太不可思议了，因为这段代码不是我的，它应该在以前的版本中编译).复制
c++ - 错误 - : 'QObject::QObject' : cannot access private member declared in class 'QObject'
我试图返回一个派生自 QObject 的类，但出现以下错误 Error : 'QObject::QObject' : cannot access private member declared in
c++ - QObject 派生类型是否需要父 QObject？
我正在编写一些派生自 QObject 的 Qt 类，它看起来像: class A : public QObject { Q_OBJECT public: A() : QObject() {}
c++ - 为什么我可以将 QObject* 分配给 QObject？
考虑以下代码: #include class A : public QObject { Q_OBJECT public: A(QObject* parent = 0)
c++ - QObject::connection(const QObject*, const char*, const char*, Qt::ConnectionType) "Cannot convert argument 3 from ' fileProcessor' to const QObject *"
我似乎需要 QObject 类型的 p 实例，我已经扩展了 QObject 并在 fileprocessor.h 中定义了关键字 Q_OBJECT，我不确定我还能做什么。 -文件处理器.h #ifnd
qt - 为什么我不能在 QObject 只是间接基类的类中设置 QObject 父级？
我有一个继承 QObject 的类 BatchItem，还有几个继承自 BatchItem 的类: #ifndef BATCHITEM_H #define BATCHITEM_H #include
c++ - 没有要调用的匹配函数 - 编译器说我在调用 (QObject *) 时调用 (QObject *&)
这是代码: void invokeQMLFunction2Arg(QObject * object, QString func, QVariant p1, QVariant p2) { QMe
c++ - QObject::connect 函数中的 QObject* 上下文
我读过 documentation对于 QObject::connect(对于 Qt 5.4)，但我对重载有疑问 QMetaObject::Connection QObject::connect(co
python - 无法在 QObject 上调用 findChild(QObject, 'child' )。无返回值
我最近一直在使用QTCreator，我爱上了ATM。不幸的是，我想将它与 Python 一起使用，但我遇到了问题。我遇到的最大问题是发现我的应用程序上下文的子级返回 None。 main.py imp
c++ - #include 和#include 的区别
使用 #include 有什么区别吗？和 #include ？这两个似乎都有效，所以必须有一些原因来说明为什么 #include是首选吗？最佳答案任何不带 .h 扩展名的标准 Qt 头文件都保证
python - PyQt4 - 无法在继承自 QGraphicsItem (继承 QObject)的类中使用 QObject 的函数
我写的Python代码看起来像这样: class Regularblock(QGraphicsItem): def __init__(self): super(QGraphic
c++ - 当 QObject 被销毁时，Qt 可以安排将 QObject* 设置为 nullptr 吗？
Qt 框架有一个 signal for all QObjects which is emmited before destruction那个QObject。此事件可用于在它指向的对象被销毁时自动清空一
c++ - 错误: 'QObject' 是 'SerialPort' QObject::connect(&uartObj, SIGNAL(readDone(QByteArray)), this, SLOT(hdlRxDone(QByteArray))) 的模糊基数；
我想创建 SerialPort 类，它可以自动接收消息，然后发出信号。但是当我编译它时显示错误信息: error: 'QObject' is an ambiguous base of 'Serial
qt - QObject 的空模式
(C++/Qt) 我有一个指向 QObject 的智能指针。让我们说一个 QWeakPointer。由于某些外部原因(可能发生在另一个对象中或由于某个事件)，指向的对象可能会被销毁。因为我有一个智能指
qt - QObject 的模糊析构函数？
QObject 析构函数的 Qt 引用说: 进出该对象的所有信号都会自动断开，该对象的任何未决发布事件都会从事件队列中删除。但是，使用 deleteLater() 通常比删除更安全直接一个 QObje
qt - QObject 无法为处于不同线程中的父对象创建子对象
您好，我需要从后台进行一些套接字通信，我为此使用了QtConcurrent::run，但给了我警告。 QObject: Cannot create children for a parent that
qt - 如何从父级中删除 QObject
如何打破 QObject 的父子所有权？似乎不再有明确的方法来做到这一点。打电话就够了 QObject::setParent(NULL) 最佳答案你是对的。制作 QObject一个孤儿，简单地做 /

行者123

个人简介

我是一名优秀的程序员,十分优秀！

作者热门文章

滴滴打车优惠券免费领取

全站热门文章

首页

博学

6Ren·AI

商城

python - QObject::setParent:无法设置父级，新父级位于Python中的不同线程中