QTreeWidgetItem* item = new QTreeWidgetItem(); item->setFlags(item->flags() | Qt::ItemIsSelectable);
QTreeWidgetItem* item = new QTreeWidgetItem(); item->setFlags(item->flags() | Qt::ItemIsEditable);
QTreeWidgetItem* item = new QTreeWidgetItem(); item->setFlags(item->flags() | Qt::ItemIsEnabled);
QTreeWidgetItem* item = new QTreeWidgetItem(); item->setFlags(item->flags() | Qt::ItemIsUserCheckable);The package/library for QTreeWidgetItem flags is Qt.