Simple Xamarin MessagingCenter example.

MessagingCenterExample.cs

//Without sending arguments

//Subscribe
MessagingCenter.Subscribe<object> (this, "Arrived", (sender) => {
    // do something whenever the "Arrived" message is sent from whatever type 
    //<object> is.
});

//Send
//All subscribers to "Arrived" of type "this" will be notified.
MessagingCenter.Send<object> (this, "Arrived");

//Unsubscribe
MessagingCenter.Unsubscribe<object> (this, "Arrived");



//With sending arguments.

//Subscribe
MessagingCenter.Subscribe<object, string> (this, "Arrived", (sender, string) => {
    // do something whenever the "Arrived" message is sent from whatever type 
    //<object> is.
    myEntry.Text = string;
});

//Send
//All subscribers to "Arrived" of type "this" will be notified.
MessagingCenter.Send<object, string> (this, "Arrived", "New String");

//Unsubscribe
MessagingCenter.Unsubscribe<object, string> (this, "Arrived");