errors in addressbook tutorial?

[Eolo]

First, greetings to all. I just initiated in Qt 4.3.4. and I have been following the tutorial that accompanies the installation 'addressbook'. I have scrupulously followed all the steps but when I arrive while adding this code:

if (dialog.exec()) { 
QString name = dialog.name(); 
QString email = dialog.email(); 
if (!name.isEmpty() && !email.isEmpty()) { 
QListWidgetItem *item = new QListWidgetItem(name, ui.addressList); 
item->setData(Qt::UserRole, email); 
ui.addressList->setCurrentItem(item); 
} 
}

if (dialog.exec()) { 
QString name = dialog.name(); 
QString email = dialog.email(); 
if (!name.isEmpty() && !email.isEmpty()) { 
QListWidgetItem *item = new QListWidgetItem(name, ui.addressList); 
item->setData(Qt::UserRole, email); 
ui.addressList->setCurrentItem(item); 
} 
}

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to compile, I get the errors:

`QListWidgetItem' undeclared (first use this function)
`QListWidgetItem' has not been declared
`item' undeclared (first use this function)

What is that? Do the tutorial has mistakes or I who is wrong? I appreciate any clarification to my question. Thanks.