Your model needs to implement QAbstractItemModel::setData() and emit the dataChanged() signal as described in the docs. The default item delegate used by the table view should handle the return key and call this method with the new value. (In other words, the base QTableView will just work). You also need to implement the QAbstractItemModel::flags() method to add the Qt::ItemIsEditable flag to the defaults for thhose items the user is allowed to edit.
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