using System;

using System.Collections.Generic;

using System.Collections.ObjectModel;

public class MyClass: MyInterface

{

    public MyClass() 

    {

        this.ReceivedNewObjects += SaveNewObjects;

    }

    //Calls a WebService to check for new Objects

    //Called by a timer in the ViewModel

    public ICollection<Object> GetNewObjects()

    {

        var newObjects = new Collection<Object>(); //actually calls a service here

        if(newObjects.Count>0)

        {

            OnReceivingNewObjects(newObjects);

        }

​

        return new Collection<Object>();

    }

    private void SaveNewObjects(object sender, ICollection<Object> newObjects)

    {

        //Calls DataLayer to save new objects

    }

    public event EventHandler<ICollection<Object>> ReceivedNewObjects;

     protected virtual void OnReceivingNewObjects(ICollection<Object> newObjects)

        {

            ReceivedNewObjects?.Invoke(this, newObjects);

        }

​

}

​

public interface MyInterface

{

    ICollection<Object> GetNewObjects();

    event EventHandler<ICollection<Object>> ReceivedNewObjects;

}

​