creating/deleting children does not change the refcount of a QObject, since this is done purely in C++
On Thu, 2012-03-29 at 19:22 +0800, Goldfish Huang wrote: > Hi, all. > > I am doubted how SIP deal with QObject's cycle reference, when I try > to fix some unknown memory leaks. It seems that SIP only keep a > reference to QObject, whatever how many children it has. Then a > QObject must have not less than 2 reference count, one from Python and > another from SIP. The question is, when I delete the QObject from > Python, how SIP detects that and decrease the reference? It supposed > that the reference count will be decreased to 1, and never destructed. > > The code pastes below: > > import sys, gc > from PyQt4.QtCore import * > > gc.disable() > c=QObjectCleanupHandler() > o1=QObject() > QObject(o1), QObject(o1) > c.add(o1) > print sys.getrefcount(o1) , len(o1.children()) > > #delete a child but the reference count remains 2. > o1.children()[0].setParent(None) > print sys.getrefcount(o1) , len(o1.children()) > > #decrease reference count of o1 by one. > del o1 > > #It is destructed! > print c.isEmpty() > > > -- > 免服务器办公室聊天软件、笔记本、日记本：http://besteam.im/。 > Python及Qt相关Blog：http://besteam.im/blogs/ > _______________________________________________ > PyQt mailing list PyQt@riverbankcomputing.com > http://www.riverbankcomputing.com/mailman/listinfo/pyqt _______________________________________________ PyQt mailing list PyQt@riverbankcomputing.com http://www.riverbankcomputing.com/mailman/listinfo/pyqt
