public MainPage()
{
this.InitializeComponent();
DataContext = this;
StoreClass store = new StoreClass();
InStockList.ItemsSource = store.GetCurrentStockList();
StockToAddList.ItemsSource = store.GetCurrentDeliverysList();
CustomerList = new ObservableCollection <CustomerClass>(store.GetCurrentCustomerList());
StockList = new ObservableCollection <StockClass>(store.GetCurrentStockList());
CustomerOrders = new ObservableCollection <CustomerOrderClass>(store.GetCurrentCustomerOrders());
}