MessagingCenterHelper.cs

public class MsgHub
{
	public static MsgHub Instance = new MsgHub();

	public static void Send<TArgs> (TArgs args) 
	{
		var msg = args.GetType ().Name;

		MessagingCenter.Send<MsgHub, TArgs> (Instance, msg, args);
	}

	public static void Subscribe<TArgs> (object subscriber, Action<TArgs> callback)
	{
		var msg = typeof(TArgs).Name;

		MessagingCenter.Subscribe<MsgHub, TArgs> (subscriber, msg, (s, a) => callback(a), Instance);
	}

	public static void Unsubscribe<TArgs> (object subscriber)
	{
		var msg = typeof(TArgs).Name;

		MessagingCenter.Unsubscribe<MsgHub, TArgs> (subscriber, msg);
	}
}