public CommoditiesViewModel(IInventoryManagementModel inventoryManagementModel)
        {
            _inventoryManagementModel = inventoryManagementModel;

            // set up event handling
            _inventoryManagementModel.SaveChangesComplete += _inventoryManagementModel_SaveChangesComplete;
            _inventoryManagementModel.GetCommoditiesComplete += _inventoryManagementModel_GetCommoditiesComplete;
            _inventoryManagementModel.PropertyChanged += _inventoryManagementModel_PropertyChanged;

            // load all commodities
            _inventoryManagementModel.GetCommoditiesAsync();
        }
        public CommoditiesViewModel(IInventoryManagementModel inventoryManagementModel)
        {
            _inventoryManagementModel = inventoryManagementModel;

            // set up event handling
            _inventoryManagementModel.SaveChangesComplete    += _inventoryManagementModel_SaveChangesComplete;
            _inventoryManagementModel.GetCommoditiesComplete += _inventoryManagementModel_GetCommoditiesComplete;
            _inventoryManagementModel.PropertyChanged        += _inventoryManagementModel_PropertyChanged;

            // load all commodities
            _inventoryManagementModel.GetCommoditiesAsync();
        }