[PyQt] UTF-8 files handling in PyQT4

[piotr maliński]

Hi, I'm writing a simple text editor in PyQT4. It works for ASCII
characters but I use UTF-8 encoded files with non-ASCI characters like
Polish letters (łóżźć etc.) I've used the "simple" way:

###########################
import sys
from PyQt4 import QtCore, QtGui
from edytor import Ui_notatnik

class StartQT4(QtGui.QMainWindow):
	def __init__(self, parent=None):
		QtGui.QWidget.__init__(self, parent)
		self.ui = Ui_notatnik()
		self.ui.setupUi(self)
		QtCore.QObject.connect(self.ui.button_open,QtCore.SIGNAL("clicked()"),
self.file_dialog)
		QtCore.QObject.connect(self.ui.button_save,QtCore.SIGNAL("clicked()"),
self.file_save)
	def file_dialog(self):
		fd = QtGui.QFileDialog(self)
		self.filename = fd.getOpenFileName()
		from os.path import isfile
		if isfile(self.filename):
			text = open(self.filename).read()
			self.ui.editor_window.setText(text)
	def file_save(self):
		from os.path import isfile
		if isfile(self.filename):
			file = open(self.filename, 'w')
			file.write(self.ui.editor_window.toPlainText())
			file.close()

if __name__ == "__main__":
	app = QtGui.QApplication(sys.argv)
	myapp = StartQT4()
	myapp.show()
	sys.exit(app.exec_())
##############################
It works ok for ASCI characters but when I open a file with Polish
letters they aren't displayed properly (textEdit) - also saving a file
with such letters won't save them correctly.

Similar with QFile:
##############################
# -*- coding: utf-8 -*-
import sys
from PyQt4 import QtCore, QtGui
from edytor import Ui_notatnik

class StartQT4(QtGui.QMainWindow):
	def __init__(self, parent=None):
		QtGui.QWidget.__init__(self, parent)
		self.ui = Ui_notatnik()
		self.ui.setupUi(self)
		QtCore.QObject.connect(self.ui.button_open,QtCore.SIGNAL("clicked()"),
self.file_dialog)
		QtCore.QObject.connect(self.ui.button_save,QtCore.SIGNAL("clicked()"),
self.file_save)
	def file_dialog(self):
		fd = QtGui.QFileDialog(self)
		self.filename = fd.getOpenFileName()
		from os.path import isfile
		if isfile(self.filename):
			s = QtCore.QFile(str(self.filename))
			s.open(QtCore.QIODevice.ReadOnly)
			self.ui.editor_window.setPlainText(str(s.readAll()))
			s.close()
	def file_save(self):
		from os.path import isfile
		if isfile(self.filename):
			s = QtCore.QFile(str(self.filename))
			s.open(QtCore.QIODevice.WriteOnly)
			s.writeData(str(self.ui.editor_window.toPlainText()))
			s.close()

if __name__ == "__main__":
	app = QtGui.QApplication(sys.argv)
	myapp = StartQT4()
	myapp.show()
	sys.exit(app.exec_())
#######################################
but when I try to save the file with Polish letters I get:

UnicodeEncodeError: 'ascii' codec can't encode characters in position
20-23: ordinal not in range(128)