public ValueConverterViewModel() { Factory = new NumberConverterFactory(); ConverterNames = new ObservableCollection <string>(); foreach (string name in Factory.ConverterNames) { ConverterNames.Add(name); } FromConverterName = Factory.ConverterNames.First(); ToConverterName = Factory.ConverterNames.First(); FromConverter = Factory.getConverter(FromConverterName); ToConverter = Factory.getConverter(ToConverterName); FromText = "0"; ToText = "0"; ConvertCommand = new RelayCommand(ConvertNumbers); }