protected override void OnCreate(Bundle savedInstanceState)
{
base.OnCreate(savedInstanceState);
SetContentView(Resource.Layout.Checkout_layout);
Cheeseknife.Inject(this);
products = Ultilities.GetData <Product>("data.json");
adapter = new BillAdapter(products);
rvProducts.SetLayoutManager(new LinearLayoutManager(this));
rvProducts.SetAdapter(adapter);
tvBillMoney.Text = products.Sum(p => p.Count * p.UnitPrice) + " vnd";
}