[PyKDE] PyQt4 problems with underlying C/C++ objects [weird]

[Krystian Samp]

Hi all,

I've got the following error:

Traceback (most recent call last):
  File "test2.py", line 47, in mousePressEvent
    item = MyItem2(self.options)
  File "test2.py", line 10, in __init__
    i.setParentItem(self)
RuntimeError: underlying C/C++ object has been deleted

for this code (I've tried to make it as short as possible):

import sys
from PyQt4 import QtGui, QtCore

class MyItem2(QtGui.QGraphicsItem):
    def __init__(self, items):
        QtGui.QGraphicsItem.__init__(self)

        self.items = items
        for i in self.items:
            i.setParentItem(self)

    def paint(self, painter, option, widget):
        painter.drawEllipse(0, 0, 10, 10)

    def boundingRect(self):
        return QtCore.QRectF(0, 0, 20, 20)


class MyItem1(QtGui.QGraphicsItem):
    def __init__(self):
        QtGui.QGraphicsItem.__init__(self)

    def paint(self, painter, option, widget):
        painter.drawEllipse(0, 0, 20, 20)

    def boundingRect(self):
        return QtCore.QRectF(0, 0, 20, 20)


class MyItem(QtGui.QGraphicsItem):
    def __init__(self, options):
        QtGui.QGraphicsItem.__init__(self)

        self.options = options
        self.activated = False
        self.items = []

    def paint(self, painter, option, widget):
        pass

    def boundingRect(self):
        return QtCore.QRectF(-100, -100, 200, 200)

    def mousePressEvent(self, event):
        self.activated = not self.activated
        if self.activated:
            item = MyItem2(self.options)
            self.scene().addItem(item)
            self.items.append(item)
            item.setParentItem(self)
        if not self.activated:
            for i in self.items:
                i.setParentItem(None)
                self.scene().removeItem(i)
            self.items = []

class MyView(QtGui.QGraphicsView):
    def __init__(self):
        QtGui.QGraphicsView.__init__(self)

        self.scene = QtGui.QGraphicsScene()

        self.items = [MyItem1(), MyItem1(), MyItem1()]
        self.item = MyItem(self.items)

        self.scene.addItem(self.item)
        self.setScene(self.scene)

# main program
app = QtGui.QApplication(sys.argv)
view = MyView()
view.show()

sys.exit(app.exec_())

After running it, click several times on the 'canvas' to see the error.
It is strange. The error concerns objects which I hold in MyItem.objects. I
do not understand why the underlying objects are lost. Can anyone explain me
that?
Moreover if I comment the line 'self.items = []' then there is no such
error. Is it possible that this assignment destroys C/C++ objects under the
curtain? Hard to believe.

best regards,
Krystian
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