CurrentCellActivatingCallback typedef
        CurrentCellActivatingCallback =
     bool Function(RowColumnIndex newRowColumnIndex, RowColumnIndex oldRowColumnIndex)
    
    
Signature for SfDataGrid.onCurrentCellActivating callback.
Implementation
typedef CurrentCellActivatingCallback =
    bool Function(
      RowColumnIndex newRowColumnIndex,
      RowColumnIndex oldRowColumnIndex,
    );