private void ViewModelChanged(object sender, DependencyPropertyChangedEventArgs e)
        {
            this.viewModel_ = this.DataContext as InstrumentSelectorViewModel;

            Dictionary<string,InstrumentBaseViewModel>.ValueCollection valueList
                = new Dictionary<string, InstrumentBaseViewModel>.ValueCollection(this.viewModel_.PrototypeList_);

            this.prototypeDataGrid_.ItemsSource = valueList;
            
        }