In many situations, we only need to present relatively small numbers of items to the user. In these common cases, we can use Qt's convenience item view classes (QListWidget, QTableWidget, and QTReeWidget) and populate them with items directly.
For large data sets, duplicating the data is often not an option. In these cases, we can use Qt's views (QListView, QTableView, and QtreeView), in conjunction with a data model, which can be a custom model or one of Qt's predefined models. For example, if the data set is held in a database, we can combine a QTableView with a QSqlTableModel.
