[PyQt] QObject: Cannot create children for a parent that is in a different thread. How to edit another threads objects?

Soumen banerjee soumen08 at gmail.com
Tue Sep 15 01:27:42 BST 2009


I cant understand what im doing wrong. Heres the code
gui.py:
from PyQt4 import QtCore, QtGui
import sys
from subprocess import Popen
class Ui_MainWindow(object):
	fileinit=False
	paused=True
	quit=False
	filename=""
	def setupUi(self, MainWindow):
		MainWindow.setObjectName("MainWindow")
		MainWindow.resize(394, 414)
		self.centralwidget = QtGui.QWidget(MainWindow)
		self.centralwidget.setObjectName("centralwidget")
		self.scrollArea = QtGui.QScrollArea(self.centralwidget)
		self.scrollArea.setGeometry(QtCore.QRect(19, 9, 361, 281))
		self.scrollArea.setWidgetResizable(True)
		self.scrollArea.setObjectName("scrollArea")
		self.scrollAreaWidgetContents = QtGui.QWidget(self.scrollArea)
		self.scrollAreaWidgetContents.setGeometry(QtCore.QRect(0, 0, 357, 277))
		self.scrollAreaWidgetContents.setObjectName("scrollAreaWidgetContents")
		self.textEdit = QtGui.QTextEdit(self.scrollAreaWidgetContents)
		self.textEdit.setGeometry(QtCore.QRect(-7, -6, 371, 291))
		self.textEdit.setObjectName("textEdit")
		self.scrollArea.setWidget(self.scrollAreaWidgetContents)
		self.pushButton = QtGui.QPushButton(self.centralwidget)
		self.pushButton.setGeometry(QtCore.QRect(30, 310, 80, 25))
		self.pushButton.setObjectName("pushButton")
		self.pushButton_2 = QtGui.QPushButton(self.centralwidget)
		self.pushButton_2.setGeometry(QtCore.QRect(139, 310, 91, 25))
		self.pushButton_2.setObjectName("pushButton_2")
		self.pushButton_3 = QtGui.QPushButton(self.centralwidget)
		self.pushButton_3.setGeometry(QtCore.QRect(280, 310, 80, 25))
		self.pushButton_3.setObjectName("pushButton_3")
		MainWindow.setCentralWidget(self.centralwidget)
		self.menubar = QtGui.QMenuBar(MainWindow)
		self.menubar.setGeometry(QtCore.QRect(0, 0, 394, 23))
		self.menubar.setObjectName("menubar")
		MainWindow.setMenuBar(self.menubar)
		self.statusbar = QtGui.QStatusBar(MainWindow)
		self.statusbar.setObjectName("statusbar")
		MainWindow.setStatusBar(self.statusbar)

		self.retranslateUi(MainWindow)
		QtCore.QObject.connect(self.pushButton, QtCore.SIGNAL("clicked()"), self.Open)
		QtCore.QObject.connect(self.pushButton_2,
QtCore.SIGNAL("clicked()"), self.Pause)
		QtCore.QObject.connect(self.pushButton_3,
QtCore.SIGNAL("clicked()"), self.Quit)
		QtCore.QMetaObject.connectSlotsByName(MainWindow)

	def retranslateUi(self, MainWindow):
		MainWindow.setWindowTitle(QtGui.QApplication.translate("MainWindow",
"MainWindow", None, QtGui.QApplication.UnicodeUTF8))
		self.pushButton.setText(QtGui.QApplication.translate("MainWindow",
"Open", None, QtGui.QApplication.UnicodeUTF8))
		self.pushButton_2.setText(QtGui.QApplication.translate("MainWindow",
"Pause/Resume", None, QtGui.QApplication.UnicodeUTF8))
		self.pushButton_3.setText(QtGui.QApplication.translate("MainWindow",
"Quit", None, QtGui.QApplication.UnicodeUTF8))
	def Pause(self):
		print "Pause"
		self.paused=not(self.paused)
	def Quit(self):
		self.quit=True
		print "setting quit"
	def Open(self):
		print "Open"
		self.filename=QtGui.QFileDialog.getOpenFileName()
		self.filename=str(self.filename)
		try:
			f=open("book.txt","r")
		except IOError:
			f=open("log.txt",'w')
			f.write('0')
			f.close()
		old=f.read(20)
		f.close()
		f=open(self.filename,'r')
		new=f.read(20)
		f.close()
		if(old!=new):
			f=open("log.txt",'w')
			f.write('0')
			f.close()
			f=open("book.txt",'w')
			f.write(new)
			f.close()
		self.fileinit=True
		print "setting fileinit"
		
and heres the main.py

from PyQt4 import QtCore, QtGui
import sip,gui
import sys
from subprocess import Popen
from threading import Thread
class AppThread(Thread):
	appinit=False
	def run(self):
		self.app = QtGui.QApplication(sys.argv)
		MainWindow = QtGui.QMainWindow()
		self.ui = gui.Ui_MainWindow()
		self.ui.setupUi(MainWindow)
		MainWindow.show()
		self.appinit=True
		sys.exit(self.app.exec_())
class Speak(Thread):
	def run(self):
		print "starting speaker"
		try:
			log=open("log.txt",'r')
			print log
			self.index=log.read()
			log.close()
			self.index=int(self.index)
		except IOError:
			print "setting new"
			index=0
#by now, index has been defined for both a new and an old book
		self.book=open(a.ui.filename,'r')
		self.book.seek(self.index)
		while(a.ui.quit==False):
			if (a.ui.paused==False):
				sen=self.readsen()
********			a.ui.textEdit.setText(sen)
				command="soundwrapper espeak "+' " '+sen+' " '
				k=Popen(command,shell=True)
				k.wait()
		print "quitted loop"
		index=self.book.tell()
		log=open("log.txt","w")
		log.write(str(index))
		log.close()
		print "calling exit"
		a.app.exit()
		sys.exit()
	def readsen(self):
		line=""
		sen=""
		while(line.find(".")== -1):
			sen=sen+line
			line=self.book.readline()
		sen=sen+line[0:line.find(".")+1]
		self.book.seek(self.book.tell()-len(line)+line.find(".")+1)
		return sen
a=AppThread()
a.start()
while 1:
	if a.appinit== True:
		if a.ui.fileinit==True:	
			s=Speak()
			s.start()
			break

Look at the line with many stars at the left. Is that an incorrect way
of calling the setText method of the textEdit in the other thread?
Pls Help,
Regards
Soumen


More information about the PyQt mailing list