public AssignedPartsViewModel() { ScanCommand = new AsyncCommand(Scan); SearchCommand = new AsyncCommand(Search); RemoveItemsCommand = new AsyncCommand(RemoveItems); Items = new ObservableRangeCollection <PartUsage>(); SelectedItems = new ObservableRangeCollection <PartUsage>(); PartKeeper = new PartKeeper(); PartUsageKeeper = new PartUsageKeeper(); }