void collectionList_SelectionChanged(System.Object sender, Xamarin.Forms.SelectionChangedEventArgs e)
        {
            if (collectionList.SelectedItem == null)
            {
                return;
            }

            var userObject = (e.CurrentSelection.FirstOrDefault() as Faculty);

            if (userObject != null)
            {
                string current = userObject.Name;

                Debug.WriteLine($"current selected faculty:{current}");

                var newPage = new ContactDetailsPage(new User {
                    Name = current
                });
                //var newPage = new ContactDetailsPage(user: userObject);
                Navigation.PushAsync(newPage);
            }



            collectionList.SelectedItem = null;
        }
        void OnCollectionViewSelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            if (collectionList.SelectedItem == null)
            {
                return;
            }

            var userObject = (e.CurrentSelection.FirstOrDefault() as User);

            if (userObject != null)
            {
                string current = userObject.Name;

                Debug.WriteLine($"current selected item:{current}");

                var newPage = new ContactDetailsPage(user: userObject);
                Navigation.PushAsync(newPage);
            }



            collectionList.SelectedItem = null;
        }