notiXamarin9.txt

// MainActivity

public override bool OnCreateOptionsMenu(IMenu menu)
        {
            MenuInflater.Inflate(Resource.Menu.newsActionMenu, menu);
            return base.OnCreateOptionsMenu(menu);
        }

        public override bool OnOptionsItemSelected(IMenuItem item)
        {
            switch (item.ItemId)
            {
                case Resource.Id.action_read_later:
                    HandleReadLater();
                    return true;
                default:
                    return base.OnOptionsItemSelected(item);
            }
        }

        private void HandleReadLater()
        {
            Toast.MakeText(this, "read later", ToastLength.Short).Show();
        }

// En newsActionMenu.xml

<?xml version="1.0" encoding="utf-8" ?>
<!--For all properties see: http://developer.android.com/guide/topics/resources/menu-resource.html-->
<menu xmlns:android="http://schemas.android.com/apk/res/android">
  
  <item android:id="@+id/action_read_later"
         android:showAsAction="always"
         android:icon="@drawable/read_later_white" />
  
</menu>