Crash in takeChild() while deleting a QTreeWidgetItem

LAXMIU

Hi,

I have an application which uses QTreeWidget to create a tree of 2 columns. When I doble click on any item in the tree and use DELETE key to delete, it deletes the rows contents and then clicking on any other place in the tree (for example clicking on next row to remove the mouse focus) deletes the row and the application crashes.

The crash is coming in line ModelForm::deleteCurrent() : c = p->takeChild(indexOfChild(c));

Please note that the application DOES NOT crashes using Qt 4.4.1 , but it CRASHES when I use Qt. 4.5.3

Following is the stacktrace:
@
#0 0x06a84823 in QPersistentModelIndex::operator QModelIndex const& () from
/hm/cmind/cic/MS/IC615/DEL/lnx86/tools/Qt/32bit/lib/libQtCore.so.4
#1 0x0208d39f in QAbstractItemView::updateEditorGeometries () from
/hm/cmind/cic/MS/IC615/DEL/lnx86/tools/Qt/32bit/lib/libQtGui.so.4
#2 0x0207edd2 in QAbstractItemViewPrivate::_q_rowsRemoved () from
/hm/cmind/cic/MS/IC615/DEL/lnx86/tools/Qt/32bit/lib/libQtGui.so.4
#3 0x020c5eaa in QTreeViewPrivate::rowsRemoved () from
/hm/cmind/cic/MS/IC615/DEL/lnx86/tools/Qt/32bit/lib/libQtGui.so.4
#4 0x020c64eb in QTreeView::rowsAboutToBeRemoved () from
/hm/cmind/cic/MS/IC615/DEL/lnx86/tools/Qt/32bit/lib/libQtGui.so.4
#5 0x0208a865 in QAbstractItemView::qt_metacall () from
/hm/cmind/cic/MS/IC615/DEL/lnx86/tools/Qt/32bit/lib/libQtGui.so.4
#6 0x020d12ba in QTreeView::qt_metacall () from
/hm/cmind/cic/MS/IC615/DEL/lnx86/tools/Qt/32bit/lib/libQtGui.so.4
#7 0x0210a12a in QTreeWidget::qt_metacall () from
/hm/cmind/cic/MS/IC615/DEL/lnx86/tools/Qt/32bit/lib/libQtGui.so.4
#8 0x06aa5583 in QMetaObject::activate () from
/hm/cmind/cic/MS/IC615/DEL/lnx86/tools/Qt/32bit/lib/libQtCore.so.4
#9 0x06aa61e2 in QMetaObject::activate () from
/hm/cmind/cic/MS/IC615/DEL/lnx86/tools/Qt/32bit/lib/libQtCore.so.4
#10 0x06adf7ff in QAbstractItemModel::rowsAboutToBeRemoved () from
/hm/cmind/cic/MS/IC615/DEL/lnx86/tools/Qt/32bit/lib/libQtCore.so.4
#11 0x06a86965 in QAbstractItemModel::beginRemoveRows () from
/hm/cmind/cic/MS/IC615/DEL/lnx86/tools/Qt/32bit/lib/libQtCore.so.4
#12 0x021074c6 in QTreeModel::beginRemoveItems () from
/hm/cmind/cic/MS/IC615/DEL/lnx86/tools/Qt/32bit/lib/libQtGui.so.4
#13 0x02107f89 in QTreeWidgetItem::takeChild () from
/hm/cmind/cic/MS/IC615/DEL/lnx86/tools/Qt/32bit/lib/libQtGui.so.4
#14 0x0a554ee6 in ModelForm::deleteCurrent ()
@

The code is as follows:
main.cpp:
@
#include <QApplication>
#include <QHeaderView>
#include "ModelForm.h"

int main(int argc, char *argv[])
{
QApplication app(argc, argv);
app.setStyle("windows");
ModelForm *treeWidget = new ModelForm();
return app.exec();
}
@

ModelForm.h
@
#include "ModelFormDelegate.h"
#include <QtCore/QVariant>
#include <QtGui/QtGui>

#define CHECKBOXCOL 0
#define FILENAMECOL 1
#define SECTIONCOL 2
#define GLOBALBLOCKNAME "Global Model Files"
#define EMPTYROWTEXT "<Click here to add model file>"
#define BLOCKCOL 0
#define FILESTR "File ""
#define NOTEXIST "" does not exist."

class ModelForm : public QWidget
{
Q_OBJECT

public:
QTreeWidget modelTree;
ModelForm( QWidget parent = 0, Qt::WFlags fl = 0 );
~ModelForm();
virtual bool event ( QEvent * e );

signals:
void deleteRow(QTreeWidgetItem*, int);

public slots:
void deleteCurrent();

private slots:
void itemChanged(QTreeWidgetItem * item,int col);
void deleteRowSlot(QTreeWidgetItem*, int);
void addModelFilesSlot(const QStringList&);
private:
void resizeEvent(QResizeEvent * event) {};
QTreeWidgetItem* getBlockItem(QString blockname);
void resetModelForm();
void addBlankRow(QTreeWidgetItem* item);

    ModelFormDelegate* _delegate;
    QTreeWidgetItem * globalModels;

};
@

ModelFormDelegate.h
@
#include <QItemDelegate>
#include <Qt/QtGui>

class QAbstractItemView;
class ModelForm;

class ModelFileEditor : public QWidget
{

Q_OBJECT

public:
ModelFileEditor( QWidget* parent, ModelForm* qwidget, Qt::WFlags fl = 0 );
~ModelFileEditor();
QLineEdit* lineEdit;
QPushButton* btn;
static QString lastFilePath;

signals:
void editingFinished();
void addModelFiles(const QStringList&);

private slots:
void textChangedSlot( const QString &);
void editingFinishedSlot();
private:
ModelForm* _parent;
};

class ModelFormDelegate : public QItemDelegate
{
Q_OBJECT

public:
ModelFormDelegate(QObject *parent = 0);
ModelFormDelegate(QObject *parent, QAbstractItemView aiv, ModelForm qwidget);

virtual void dummy() { };


void    paint(QPainter                      *painter,
              const QStyleOptionViewItem    &option,
              const QModelIndex             &index) const;

QWidget *createEditor(QWidget *parent, const QStyleOptionViewItem &option,
                      const QModelIndex &index) const;
void setEditorData(QWidget *editor, const QModelIndex &index) const;
void setModelData(QWidget *editor, QAbstractItemModel *model,
                  const QModelIndex &index) const;

signals:
void addModelFilesSignal(const QStringList&);

private slots:
void emitCommitData();
void addModelFiles(const QStringList&);
private:
QAbstractItemView m_view;
QMap<int,QStringList> sectionList;
ModelForm _parent;

};
@

[edit: highlight added / Denis Kormalev]
[move: No quick code / Tobias Hunger]

LAXMIU

ModelForm.cpp
@
#include "ModelForm.h"

ModelForm::ModelForm( QWidget* parent, Qt::WFlags fl):QWidget( parent, fl )
{
modelTree=new QTreeWidget;
QGridLayout *mainLayout = new QGridLayout;
QVBoxLayout *VLayout = new QVBoxLayout;
VLayout->setMargin(0);
mainLayout->setMargin(0);
VLayout->addWidget(modelTree,0);
mainLayout->addLayout(VLayout, 0,0);
setLayout(mainLayout);
_delegate = NULL;
globalModels = NULL;

_delegate = new ModelFormDelegate(modelTree,modelTree,this);
modelTree->setItemDelegate(_delegate);
modelTree->setColumnCount(3);
modelTree->header()->resizeSection(CHECKBOXCOL,60);
modelTree->header()->resizeSection(FILENAMECOL,400);
modelTree->header()->setResizeMode(FILENAMECOL, QHeaderView::Stretch);
modelTree->header()->setResizeMode(CHECKBOXCOL, QHeaderView::Interactive);
modelTree->header()->setResizeMode(SECTIONCOL, QHeaderView::Interactive);
modelTree->header()->setStretchLastSection(false);
modelTree->setContextMenuPolicy(Qt::CustomContextMenu);
modelTree->setSelectionMode(QAbstractItemView::ExtendedSelection);
modelTree->setTextElideMode(Qt::ElideLeft);
modelTree->setEditTriggers(QAbstractItemView::AllEditTriggers);

modelTree->setTabKeyNavigation(true);

QStringList labels;
labels << "" << "Model File" << "Section";
modelTree->setHeaderLabels(labels);

 resetModelForm();
       
 connect( _delegate, SIGNAL( addModelFilesSignal(const QStringList&) ),
   this, SLOT(  addModelFilesSlot(const QStringList&) ) );
 connect( modelTree, SIGNAL( itemChanged(QTreeWidgetItem *, int) ),
   this, SLOT(  itemChanged(QTreeWidgetItem *,int) ) );
 connect(this, SIGNAL(deleteRow(QTreeWidgetItem*, int)), this, SLOT(deleteRowSlot(QTreeWidgetItem*, int)));

 if (!parent) show();

}

bool ModelForm::event(QEvent *event)
{
if(event->type() == QEvent::Leave) {
QTreeWidgetItem *item = modelTree->currentItem();
if(item != NULL){
int col = modelTree->currentColumn();
ModelFileEditor *fileEdit = qobject_cast<ModelFileEditor *>(modelTree->itemWidget(item,col));
QLineEdit *lineEdit = qobject_cast<QLineEdit *>(modelTree->itemWidget(item,col));
if(fileEdit){
if(item->text(col) != fileEdit->lineEdit->text()){
item->setText(col,fileEdit->lineEdit->text());
}
}
else if(lineEdit){
if(item->text(col) != lineEdit->text()){
item->setText(col,lineEdit->text());
}
}
}
}
return QWidget::event(event);
}

void ModelForm::resetModelForm() {
modelTree->clearSelection();
QTreeWidgetItem* current = modelTree->currentItem();
if(current) {
modelTree->closePersistentEditor(current,FILENAMECOL);
}
modelTree->clear();
globalModels = new QTreeWidgetItem;
modelTree->blockSignals(true);
globalModels->setText(BLOCKCOL,GLOBALBLOCKNAME);
globalModels->setFlags(Qt::ItemIsEnabled|Qt::ItemIsUserCheckable);
modelTree->blockSignals(false);
modelTree->addTopLevelItem(globalModels);
addBlankRow(globalModels);
}

void ModelForm::addBlankRow(QTreeWidgetItem* item) {
QTreeWidgetItem* chItem = new QTreeWidgetItem;

item->addChild(chItem);
modelTree->expandItem(item);
modelTree->blockSignals(true);
chItem->setFlags(Qt::ItemIsUserCheckable | Qt::ItemIsEnabled | Qt::ItemIsDragEnabled | Qt::ItemIsEditable);
chItem->setCheckState(CHECKBOXCOL,Qt::Unchecked);
chItem->setText(FILENAMECOL,QString(EMPTYROWTEXT));
modelTree->blockSignals(false);
}

QTreeWidgetItem* ModelForm::getBlockItem( QString blockName) {
if(QString::compare(QString(GLOBALBLOCKNAME),blockName) == 0) {
return globalModels;
} else {
int itemCount = modelTree->topLevelItemCount();
for(int i=0; i<itemCount;i++) {
if(QString::compare(modelTree->topLevelItem(i)->text(BLOCKCOL),blockName) == 0) {
return modelTree->topLevelItem(i);
}
}
}
return NULL;
}
void ModelForm::itemChanged( QTreeWidgetItem * item,int col) {
if(col == FILENAMECOL) {
QString file = item->text(FILENAMECOL);
if(item->parent() != NULL) {
QTreeWidgetItem* p = item->parent();
int index = p->indexOfChild(item);
if((index == p->childCount() -1) && (file != QString(EMPTYROWTEXT))) {
if(file.isEmpty()){
modelTree->blockSignals(true);
item->setText(FILENAMECOL,QString(EMPTYROWTEXT));
modelTree->blockSignals(false);
}
else {
item->setFlags(item->flags()|Qt::ItemIsSelectable);
item->setCheckState(CHECKBOXCOL,Qt::Checked);
addBlankRow(p);
}
} else if( index != p->childCount() -1 && (file.isEmpty() || file == QString(EMPTYROWTEXT))) {
// delete this row
emit deleteRow(p, index);
}
}
}
}

//Modified below function so that files are inserted instead of adding it at last.
void ModelForm::addModelFilesSlot(const QStringList& paths){
QTreeWidgetItem* curItem = NULL;
curItem = modelTree->currentItem();
int curCol = modelTree->currentColumn();
// if curItem is not toplevel item
if(curItem && (curCol !=-1) && (modelTree->indexOfTopLevelItem(curItem) == -1)) {
QTreeWidgetItem* parent = curItem->parent();
if(parent){
int childIndex = parent->indexOfChild(curItem);
for (int i = 0; i < paths.size(); ++i) {
QTreeWidgetItem* child = new QTreeWidgetItem();
child->setFlags(Qt::ItemIsSelectable|Qt::ItemIsUserCheckable |
Qt::ItemIsEnabled | Qt::ItemIsDragEnabled | Qt::ItemIsEditable);
child->setCheckState(CHECKBOXCOL,Qt::Checked);
child->setText(FILENAMECOL,(paths.at(i)));
parent->insertChild(((childIndex+1)+i), child);
}
}
}
}

void ModelForm::deleteRowSlot(QTreeWidgetItem* item , int index) {
QTimer::singleShot(1, this, SLOT(deleteCurrent()));
}
@

[edit: highlight added / Denis Kormalev]

LAXMIU

@
void ModelForm::deleteCurrent() {
QList<QTreeWidgetItem *> itemList = modelTree->selectedItems();
modelTree->blockSignals(true);
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();
c= p->takeChild(p->indexOfChild(c));
delete c;
if( modelTree->isItemExpanded(p)) {
modelTree->collapseItem(p);
modelTree->expandItem(p);
}
}
}
modelTree->blockSignals(false);
//now select the current item
QTreeWidgetItem curItem = modelTree->currentItem();
if(curItem){
modelTree->setItemSelected(curItem, true);
}
}
@

[edit: highlight added / Denis Kormalev]

LAXMIU

ModelFormDelegate.cpp
@
#include <QtGui/QtGui>

#include "ModelFormDelegate.h"
#include "ModelForm.h"

QString ModelFileEditor::lastFilePath = NULL;

ModelFileEditor::ModelFileEditor( QWidget* parent, ModelForm* qwidget, Qt::WFlags fl )
:QWidget( parent, fl ), _parent(qwidget)
{
lineEdit = new QLineEdit;
lineEdit->setFrame(FALSE);
btn = new QPushButton(QString(" ... "));
QHBoxLayout *mainLayout = new QHBoxLayout;
mainLayout->setMargin(0);
mainLayout->setSpacing(0);
mainLayout->addWidget(lineEdit,5);
mainLayout->addWidget(btn,0);
mainLayout->addSpacing(5);
setLayout(mainLayout);
connect(lineEdit, SIGNAL(editingFinished()), this, SIGNAL(editingFinished()));
connect(lineEdit, SIGNAL(editingFinished()), this, SLOT(editingFinishedSlot()));
connect(lineEdit, SIGNAL(textChanged(const QString &) ),this, SLOT(textChangedSlot( const QString &)));
this->setFocusProxy(lineEdit);
setTabOrder(lineEdit,btn);
}

void ModelFileEditor::editingFinishedSlot() {
f(lineEdit) {
if((lineEdit->text() != QString(EMPTYROWTEXT)) && (lineEdit->text() != QString(""))) {

QString temp(FILESTR);

temp.append(lineEdit->text());
temp.append(NOTEXIST);
lineEdit->setToolTip(temp);
}
}
}

void ModelFileEditor::textChangedSlot( const QString & text){
if(lineEdit){
lineEdit->setToolTip(text);
}
editingFinishedSlot();
}

ModelFormDelegate::ModelFormDelegate(QObject *parent)
: QItemDelegate(parent),m_view(NULL){}

ModelFormDelegate::ModelFormDelegate(QObject *parent, QAbstractItemView *aiv,ModelForm *qwidget)
: QItemDelegate(parent),m_view(aiv),_parent(qwidget){}

void ModelFormDelegate::paint(QPainter *painter,
const QStyleOptionViewItem &option,
const QModelIndex &index) const
{
int col = index.column();
int row = index.row();
int pRow = index.parent().row();
if (index.isValid() && !index.parent().isValid()) {
QModelIndex index2(index.sibling(index.row(),0));
QStyleOptionViewItem sovi(option);
sovi.rect=QRect(0, option.rect.y(),
painter->viewport().width(),
option.rect.height());
if(m_view)
sovi.rect.setX(m_view->visualRect(index2).x());
QItemDelegate::paint(painter,sovi,index2);
} else {
int rows = -1;
if(m_view)
{
rows = qobject_cast<QTreeWidget *>(m_view)->topLevelItem(pRow)->childCount();
}
QModelIndex lastRowIndex(index.sibling(rows-1,col));
QModelIndex lastColIndex(index.sibling(row,2));
int w = option.rect.width();
int h = option.rect.height();
if(index == lastRowIndex)
{
h= h-1;
}
if(index == lastColIndex)
{
w= w-1;
}
QItemDelegate::paint(painter, option, index);
painter->setPen(QColor(Qt::lightGray));
QRect myrect(option.rect.x(),option.rect.y(),w,h);
painter->drawRect(myrect);
}
}
QWidget *ModelFormDelegate::createEditor(QWidget parent,
const QStyleOptionViewItem & / option */,
const QModelIndex &index) const
{
int col = index.column();

if( !index.parent().isValid()) return NULL;

if(col == 2 ) { // section
QLineEdit *lineEdit = new QLineEdit(parent);
connect( lineEdit, SIGNAL(editingFinished()), this , SLOT(emitCommitData()));
return lineEdit;
} else if(col == 0 ){// checkBox
return NULL;
} else if(col == 3 ){// push button for browser
QPushButton * pushButton = new QPushButton(QString("..."),parent);
connect(pushButton, SIGNAL(clicked()), this, SLOT(emitCommitData()));
return pushButton;
} else if(col == 1 ){ //file
ModelFileEditor *fileEdit = new ModelFileEditor(parent,_parent);
connect(fileEdit, SIGNAL(editingFinished()), this, SLOT(emitCommitData()));
connect(fileEdit, SIGNAL(addModelFiles(const QStringList&)), this, SLOT(addModelFiles(const QStringList&)));
return fileEdit;
} else {
return NULL;
}
return NULL;
}

void ModelFormDelegate::setEditorData(QWidget *editor,
const QModelIndex &index) const
{
int col = index.column();
if(col == 2 ) {
QLineEdit *lineEdit = qobject_cast<QLineEdit *>(editor);
if( !lineEdit) {
return;
}
if((lineEdit->text())!= (index.model()->data(index).toString())) {
lineEdit->setText(index.model()->data(index).toString());
lineEdit->selectAll();
}

} else if(col == 1 ){
ModelFileEditor *fileEdit = qobject_cast<ModelFileEditor *>(editor);
if (!fileEdit) {
return;
}
if ((fileEdit->lineEdit->text())!= (index.model()->data(index).toString())) {
fileEdit->lineEdit->setText(index.model()->data(index).toString());
}
fileEdit->lineEdit->selectAll();

} else if(col == 3 ){
QPushButton *btn = qobject_cast<QPushButton *>(editor);
if (!btn)
return;
}
}

void ModelFormDelegate::setModelData(QWidget *editor, QAbstractItemModel *model,
const QModelIndex &index) const
{
int col = index.column();
if(col == 2 ) {
QLineEdit *lineEdit = qobject_cast<QLineEdit *>(editor);
if( !lineEdit) {
return;
}
model->setData(index, lineEdit->text());

} else if(col == 1 ){
ModelFileEditor *fileEdit = qobject_cast<ModelFileEditor *>(editor);
if (!fileEdit) {
return;
}
model->setData(index, fileEdit->lineEdit->text());
} else if(col == 3 ){
QPushButton *btn = qobject_cast<QPushButton *>(editor);
if (!btn)
return;
model->setData(index, true);
}
}

void ModelFormDelegate::addModelFiles(const QStringList& files)
{
emit addModelFilesSignal(files);
}
@

[edit: highlight added / Denis Kormalev]

tobias.hunger

Could you please use the code tags to format your code sections? It is hardly readable the way it is printed now!

thorbjorn

This might have something to do with @modelTree->blockSignals(true);@, which I guess could cause the view not to be entirely aware of the child removals, but I'm not sure. In any case this forum is not the proper place to report bugs, you should use "http://bugreports.qt.nokia.com/":http://bugreports.qt.nokia.com/ for that.

LAXMIU

.

LAXMIU

Hi,
I tried removing blockSignals from the deleteCurrent functionality , but it did not work out.

Thanks, Laxmi

LAXMIU

.

LAXMIU

.

DenisKormalev

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

alexander

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

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

[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

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

tobias.hunger

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

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

DenisKormalev

[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

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

Thanks,
Laxmi

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 ?