public RatesViewModel(KeeperDb db)
{
CurrencyList = Enum.GetValues(typeof(CurrencyCodes)).OfType <CurrencyCodes>().ToList();
Rows = db.CurrencyRates;
IsCollectionChanged = false;
InitFilterList();
SelectedFilter = FilterList.First(f => !f.IsOn);
var view = CollectionViewSource.GetDefaultView(Rows);
view.Filter += OnFilter;
view.SortDescriptions.Add(new SortDescription("BankDay", ListSortDirection.Ascending));
}