Crash in takeChild() while deleting a QTreeWidgetItem

DenisKormalev · wrote on 29 Sept 2010, 09:51

LAXMIU, I've added highlighting to your code, please don't forget to use it by yourself in future :)

alexander · wrote on 29 Sept 2010, 10:48

why do you use takeChild()?
try only delete item

@void ModelForm::deleteCurrent() {
QList<QTreeWidgetItem *> itemList = modelTree->selectedItems();
for(int i= 0; i <itemList.size(); i++) {
if(itemList.at(i) != NULL && itemList.at(i)->parent() != NULL) {
QTreeWidgetItem *c=itemList.at(i);
QTreeWidgetItem p = c->parent();
delete c;
}
}
//now select the current item
QTreeWidgetItem curItem = modelTree->currentItem();
if(curItem){
modelTree->setItemSelected(curItem, true);
}
}@

LAXMIU · wrote on 5 Oct 2010, 03:01

Hi Alexander,

I tried removing takeChild too, the crash now coming in the destructor of QTreeWidgetItem as follows:

#0 0x00270823 in QPersistentModelIndex::operator QModelIndex const& ()
from /net/ciclnx11d/export/home/laxmi/PERFORCE/DEL/lnx86/tools/Qt/32bit/lib/libQtCore.so.4
#1 0x0120539f in QAbstractItemView::updateEditorGeometries () from /net/ciclnx11d/export/home/laxmi/PERFORCE/DEL/lnx86/tools/Qt/32bit/lib/libQtGui.so.4
#2 0x011f6dd2 in QAbstractItemViewPrivate::_q_rowsRemoved () from /net/ciclnx11d/export/home/laxmi/PERFORCE/DEL/lnx86/tools/Qt/32bit/lib/libQtGui.so.4
#3 0x0123deaa in QTreeViewPrivate::rowsRemoved () from /net/ciclnx11d/export/home/laxmi/PERFORCE/DEL/lnx86/tools/Qt/32bit/lib/libQtGui.so.4
#4 0x0123e4eb in QTreeView::rowsAboutToBeRemoved () from /net/ciclnx11d/export/home/laxmi/PERFORCE/DEL/lnx86/tools/Qt/32bit/lib/libQtGui.so.4
#5 0x01202865 in QAbstractItemView::qt_metacall () from /net/ciclnx11d/export/home/laxmi/PERFORCE/DEL/lnx86/tools/Qt/32bit/lib/libQtGui.so.4
#6 0x012492ba in QTreeView::qt_metacall () from /net/ciclnx11d/export/home/laxmi/PERFORCE/DEL/lnx86/tools/Qt/32bit/lib/libQtGui.so.4
#7 0x0128212a in QTreeWidget::qt_metacall () from /net/ciclnx11d/export/home/laxmi/PERFORCE/DEL/lnx86/tools/Qt/32bit/lib/libQtGui.so.4
#8 0x00291583 in QMetaObject::activate () from /net/ciclnx11d/export/home/laxmi/PERFORCE/DEL/lnx86/tools/Qt/32bit/lib/libQtCore.so.4
#9 0x002921e2 in QMetaObject::activate () from /net/ciclnx11d/export/home/laxmi/PERFORCE/DEL/lnx86/tools/Qt/32bit/lib/libQtCore.so.4
#10 0x002cb7ff in QAbstractItemModel::rowsAboutToBeRemoved () from /net/ciclnx11d/export/home/laxmi/PERFORCE/DEL/lnx86/tools/Qt/32bit/lib/libQtCore.so.4
#11 0x00272965 in QAbstractItemModel::beginRemoveRows () from /net/ciclnx11d/export/home/laxmi/PERFORCE/DEL/lnx86/tools/Qt/32bit/lib/libQtCore.so.4
#12 0x0127f4c6 in QTreeModel::beginRemoveItems () from /net/ciclnx11d/export/home/laxmi/PERFORCE/DEL/lnx86/tools/Qt/32bit/lib/libQtGui.so.4
#13 0x0127f6b0 in QTreeWidgetItem::~QTreeWidgetItem () from /net/ciclnx11d/export/home/laxmi/PERFORCE/DEL/lnx86/tools/Qt/32bit/lib/libQtGui.so.4
#14 0x0804c7da in ModelForm::deleteCurrent (this=0x857ff60) at ModelForm.cpp:179

LAXMIU · wrote on 5 Oct 2010, 03:04

[quote author="Denis Kormalev" date="1285753913"]LAXMIU, I've added highlighting to your code, please don't forget to use it by yourself in future :)[/quote]

Hi Denis,
Please let me know the procedure/steps of highlighting the code. I really don't know. I am new to this forum. I could not either find any icon above for doing so.

Thanks andregards,
Laxmi

? This user is from outside of this forum · wrote on 5 Oct 2010, 05:23

just enclose only your code with the @ tag ... one before and one after your code :)

tobias.hunger · wrote on 5 Oct 2010, 09:27

LAXMIU: ... or just mark the code with your mouse and click on the second icon from the right (the one with the tooltip "Code").

tobias.hunger · wrote on 5 Oct 2010, 09:27

This thread kind of reminds me of computer magazines in the early 80ties...

DenisKormalev · wrote on 5 Oct 2010, 09:55

[quote author="Tobias Hunger" date="1286270859"]This thread kind of reminds me of computer magazines in the early 80ties...[/quote]

A lot of code and small amount of text?:)

LAXMIU · wrote on 20 Oct 2010, 03:26

I have removed unnecessary repetition of code from the thread.
Hopefully its readable now.

Thanks,
Laxmi

? This user is from outside of this forum · wrote on 20 Oct 2010, 06:56

ok laxmi, I copied all the code and tried on Qt 4.7, no crashes ... any specific reason you are still on Qt 4.5.x ?

LAXMIU · wrote on 20 Oct 2010, 07:16

Thanks a lot Chetan,

We have migrated from 4.4.1 to 4.5.3 in one of our product releases. Hopefully, we will be getting the latest Qt version attached for our next product release.

May I get any pointer that its actually a bug in Qt 4.5.3?
Have you been able to reproduce the crash in Qt 4.5.3? (If thats available with you)

Thanks,
Laxmi

LAXMIU · wrote on 20 Oct 2010, 08:11

"Qt 4.5.3 bug filed for this issue":http://bugreports.qt.nokia.com/browse/QTBUG-14572

? This user is from outside of this forum · wrote on 20 Oct 2010, 08:43

hi laxmi, can u convert it to a link

LAXMIU · wrote on 20 Oct 2010, 09:28

Hi Chetan, I did .

? This user is from outside of this forum · wrote on 20 Oct 2010, 09:53

4.5.3 is old :( ... it would map to Qt 2009.?? can you let me know