[PyQt] Segfault with QString

[Filip Gruszczyński]

> It's practically impossible to help if you just post a code fragment. The
>  problem is almost certain to be in the bits of code you haven't posted.
>
>  Try and come up with a simple but complete script that demonstrates the
>  problem so that other people can reproduce it.

OK, I have created smaller script, that segfaults. Here it is:

#!/usr/bin/python

from PyQt4 import *
from PyQt4.QtCore import *
from PyQt4.QtGui import *
import sys

USE_SILENT = 1
USE_REQUIRED = 2

class NumericContent:
	
	def __init__(self, min = 0, max = 0):
		self.min = min
		self.max = max
				
	def getValues(self):
		return range(self.min, self.max + 1)

class Element(QObject):
	
	def __init__(self, name, content = None, value = None):
		QObject.__init__(self)
		self.__name = name
		self.__content = content
		self.__value = value
		
	def getValue(self):
		return self.__value
	
	def setValue(self, value):
		self.__value = value
		
	def getName(self):
		return self.__name
		
	def hasContent(self):
		return self.__content != None
		
	def getContent(self):
		return self.__content
		
	def setContent(self, content):
		self.__content = content
		
class Attribute(Element):
	
	def __init__(self, name, content):
		Element.__init__(self, name, content)
	
	def isFinal(self):
		return True
		
	def getValues(self):
		return self.getContent().getValues()
		
	def __repr__(self):
		return str(self.getName()) + " " + str(self.getValue()) + "\n"
		
def display():
	print str(a.getValue())

if __name__ == "__main__":
	app = QApplication(sys.argv)
	widget = QWidget()
	box = QComboBox()
	button = QPushButton("Button")
	layout = QHBoxLayout()
	layout.addWidget(box)
	layout.addWidget(button)
	widget.setLayout(layout)
	widget.show()
	a = Attribute('attr', NumericContent(1, 4))
	for i in a.getValues():
		box.addItem(QString(str(i)))
	box.connect(box, SIGNAL('currentIndexChanged(QString)'), a.setValue);
	box.emit(SIGNAL('currentIndexChanged(QString)'), box.currentText())
	box.connect(button, SIGNAL('clicked()'), display)
	sys.exit(app.exec_())



To make it segfault, you just have to run it, change value in combo
box, and push the button. If you don't change the the value in the
combo box and push the button, it will correctly print the value onto
the std out.

Furthermore, if you change method

	def setValue(self, value):
		self.__value = value

to

	def setValue(self, value):
		self.__value = str(value)

it works perfectly fine. Can anyone explain me, what have I done wrong?

-- 
Filip Gruszczyński