using System;

using System.Text;

using System.ComponentModel;

using MvvmCross;

​

public class Program

{

    public static void Main()

    {

        var vm = new ViewModel();

        new View(vm);

        new View(vm);

        new View(vm);

        new View(vm);

        new View(vm);

        vm.Notify();

    }

​

    class ViewModel : INotifyPropertyChanged

    {

        public event PropertyChangedEventHandler PropertyChanged = delegate

        {

        };

        public void Notify()

        {

            PropertyChanged.Invoke(null, null);

        }

    }

​

    class View

    {

        static int count = 0;

        int number;

        ViewModel _vm;

        public View(ViewModel vm)

        {

            number = ++count;

            _vm = vm;

            vm.PropertyChanged -= ViewModel_PropertyChanged;

            vm.PropertyChanged += ViewModel_PropertyChanged;

        }

​

        private void ViewModel_PropertyChanged(object sender, System.ComponentModel.PropertyChangedEventArgs e)

        {

            Console.WriteLine($"Number {number}");

        }

    }

}