UIFIS/OUP/ViewModel.cs

using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace OUP
{
    public class ViewModel : BaseViewModel
    {

        private RelayCommand _submitCommand;

        public RelayCommand SubmitCommand
        {
            get
            {
                return _submitCommand ??
                    (_submitCommand = new RelayCommand(x =>
                    {
                        if (_product.IdProduct == 0)
                        {
                           
                            Helper.GetContext().Product.Add(_product);

                        }
                        Helper.GetContext().SaveChanges();

                    }));
            }
        }


        private Product _product;
        private ObservableCollection<Product> _products;

        public ObservableCollection<Product> Products
        {
            get => _products;
            set
            {
                _products = value;
                OnPropertyChanged();
            }
        }
        public Product Product
        {
            get => _product;
            set
            {
                _product = value;
                OnPropertyChanged();
            }
        }
        public ViewModel(Product product)
        {
            _product = product;
            _products = new ObservableCollection<Product>(Helper.GetContext().Product);
        }


    }
}