QTreeWidgetItemIterator

[dragon]

Hello anybody

I look for information for QTreeWidgetItemIterator on the net but i didn't found anything this item.
It is new in QT-4.1 but no documentation.

I want to save a file with saveFile(const QString &fileName).
see code:

void MainWindow::saveFile(const QString &fileName)
{
 
	QFile file( fileName );
	if ( !file.open(QFile::WriteOnly))
	  return;
 
	QTextStream out( &file );
	QTreeWidgetItemIterator it( contactView );
	for( ; it.current(); ++it )
		for ( unsigned int i = 0; i < 3; i++ )
			out << it.current()->text( i) << "\n";
	file.close();
 
}

void MainWindow::saveFile(const QString &fileName)
{

	QFile file( fileName );
	if ( !file.open(QFile::WriteOnly))
	  return;

	QTextStream out( &file );
	QTreeWidgetItemIterator it( contactView );
	for( ; it.current(); ++it )
		for ( unsigned int i = 0; i < 3; i++ )
			out << it.current()->text( i) << "\n";
	file.close();
	
}

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The compiler complains over this errors.
mainwindow.cpp: In member function ‘void MainWindow::saveFile(const QString&)’:
/usr/local/Trolltech/Qt-4.1.0-rc1/include/QtGui/qtreewidgetitemiterator.h:86: fout: ‘QTreeWidgetItem* QTreeWidgetItemIterator::current’ is protected
mainwindow.cpp:139: fout: within this context
mainwindow.cpp:139: fout: ‘it.QTreeWidgetItemIterator::current’ cannot be used as a function
/usr/local/Trolltech/Qt-4.1.0-rc1/include/QtGui/qtreewidgetitemiterator.h:86: fout: ‘QTreeWidgetItem* QTreeWidgetItemIterator::current’ is protected
mainwindow.cpp:141: fout: within this context
mainwindow.cpp:141: fout: ‘it.QTreeWidgetItemIterator::current’ cannot be used as a function
Where can i find documentation for QTreeWidgetItemIterator.