+You need to override \helpref{GetNumberOfRows}{wxdataviewlistmodelgetnumberofrows},
+\helpref{GetNumberOfCols}{wxdataviewlistmodelgetnumberofcols},
+\helpref{GetColType}{wxdataviewlistmodelgetcoltype} and
+\helpref{GetValue}{wxdataviewlistmodelgetvalue} in order to
+define the data model (which acts as an interface between
+your actual data and the wxDataViewCtrl).
+
+wxDataViewModel and this class (as indeed the entire wxDataViewCtrl
+code) is using \helpref{wxVariant}{wxvariant} to store data and
+its type in a generic way. wxVariant can be extended to contain
+almost any data without changes to the original class.
+