PySide和QProgressBar在不同的线程中更新 [英] PySide and QProgressBar update in a different thread

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本文介绍了PySide和QProgressBar在不同的线程中更新的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！

问题描述

这可能是一篇长文章，所以，在此先感谢与我在一起直到最后.这里的问题是(我认为这是一个非常基本的问题，只是我对PiSide和Qt的经验不足，这使我更难了.)我有一个带有一个菜单项的主窗口，假设为"Process".代码如下-

This may be a little long post, so, thanks in advance to be with me till the end. Here is the problem, (i think a fairly basic one, just my inexperience with PiSide and Qt making it harder for me.) I have a main window with one menu item, suppose "Process". the code is following -

from PySide import QtCore, QtGui

class Ui_MainWindow(object):

      def setupUi(self, MainWindow, AppObj):
            .
            .
            self.statusbar = QtGui.QStatusBar(MainWindow)
            self.statusbar.setObjectName("statusbar")
            MainWindow.setStatusBar(self.statusbar)
            .
            .
            .
           self.actionProcess = QtGui.QAction(MainWindow)
           self.actionProcess.setObjectName("actionProcess")
           self.actionProcess.triggered.connect(self.myappObj.menuActionProcess) 
           .

在这里self.myappobj指的是我创建的一个应用程序类，它充当我的应用程序的主要逻辑控制器.代码-

Here self.myappobj refers to a app class I have created which acts as the main logic controller for my app. The code -

from PySide import QtCore, QtGui
from MainWindow import Ui_MainWindow

class App(QtGui.QDialog):
      def __init__(self, parent=None):
          self.__mainWindow = QtGui.QMainWindow()
          self.__mainWindowDesignContext = Ui_MainWindow()
          self.__mainWindowDesignContext.setupUi(self.__mainWindow, self)
          self.__mainWindow.show()
      def menuActionProcess(self):
          self.processThread = BatchProcesser()
          self.progressBar = QtGui.QProgressBar()
          statusBar.addWidget(self.progressBar)
          self.progressBar.show()
          self.progressBar.setMinimum(0)
          self.progressBar.setMaximum(100)
          QtCore.QObject.connect(self.processThread, QtCore.SIGNAL("progress(int)"),self.progressBar, QtCore.SLOT("setValue(int)"), QtCore.Qt.DirectConnection)
          if not self.processThread.isRunning():
              self.processThread.exiting = False
              self.processThread.start()

因此，很容易看出我在这里要做的是创建一个主窗口.在其中添加一个名为"Process"的菜单，单击该菜单应触发应用程序类中的回调menuActionProcess方法，在其中创建一个进度条，并将其附加到主窗口的状态栏中(实际代码还有很多其他内容，我在这里给出的是重新排列的必要部分，以作为一个伪示例) 最后在上述代码中提到的BatchProcesser类中，我正在执行此操作-

So, it is easy to see that what i am trying to do here is to create a main window. Add a menu there called "Process", clicking on which should trigger the callback menuActionProcess method in the app class, where I am making a progress bar and attaching it with the Status Bar of my main window (The actual code has many other things, what i give here is the necessary parts rearranged as an pseudo example) and finally in the BatchProcesser class mentioned in the above code, I am doing this -

from PySide.QtGui import *
from PySide.QtCore import *

class BatchProcesser(QThread):
     __errorHappened = False
     def __init__(self, parent=None):
         QThread.__init__(self, parent)
         self.exiting = False
     def run(self):
         for a in range(101):
            print a
            QThread.msleep(100)
            self.emit(SIGNAL("progress(int)"), a)
            print a

据我所知，这应该在与主线程不同的线程中更新附加到状态栏的进度条.这将允许用户自由地与GUI交互.

In my understanding this should update the Progress Bar attached to the Status Bar in a different thread than the main thread. This will allow the user to interact with the GUI freely.

现在，如果我尝试冲洗它，一切都很好，直到我点击处理"菜单.然后，进度条会平缓，但不会更新，并且控制台已满，并显示错误-

Right now, If i try to rin this, everything is fine until i hit the Process menu. Then, the progress bar appeases but does not update and the console is full with error -

0 QPixmap:在GUI线程外使用像素图是不安全的

0 QPixmap: It is not safe to use pixmaps outside the GUI thread

QPixmap:在GUI线程外使用像素图是不安全的