How to update ListView on property change in Xamarin.Forms (SfListView)

You can update Grouping and Sorting of SfListView on property change by using LiveDataUpdateMode in Xamarin.Forms.

You can also refer the following article

https://www.syncfusion.com/kb/11419/how-to-update-listview-on-property-change-in-xamarin-forms-sflistview

C#

Adding GroupDescriptors, SortDescriptors and LiveDataUpdateMode properties of DataSource to ListView.

namespace ListViewXamarin
{
    public class Behavior : Behavior<SfListView>
    {
        SfListView listView;
        protected override void OnAttachedTo(SfListView bindable)
        {
            listView = bindable;
            listView.Loaded += Bindable_Loaded;
            base.OnAttachedTo(bindable);
        }
 
        private void Bindable_Loaded(object sender, ListViewLoadedEventArgs e)
        {
            listView.DataSource.LiveDataUpdateMode = LiveDataUpdateMode.AllowDataShaping;
            listView.DataSource.GroupDescriptors.Add(
                new GroupDescriptor()
                {
                    PropertyName = "ContactName",
                    KeySelector = (object obj1) =>
                    {
                        var item = (obj1 as Contacts);
                        return item.ContactName[0].ToString();
                    }
                });
            listView.DataSource.SortDescriptors.Add(
                new SortDescriptor()
                {
                    PropertyName = "ContactName"
                });
        }
        protected override void OnDetachingFrom(SfListView bindable)
        {
            listView.Loaded -= Bindable_Loaded;
            listView = null;
            base.OnDetachingFrom(bindable);
        }
    }
}

C#

Modifying item on ListView item tapped

namespace ListViewXamarin
{
    public class ContactsViewModel : INotifyPropertyChanged
    {
        public Command ChangeItem { get; set; }
 
        public ContactsViewModel()
        {
            ChangeItem = new Command(OnChangeItem);
        }
        private void OnChangeItem(object obj)
        {
            if((obj as Syncfusion.ListView.XForms.ItemTappedEventArgs).ItemType == ItemType.GroupHeader)
            {
                return;
            }
            var item = (obj as Syncfusion.ListView.XForms.ItemTappedEventArgs).ItemData as Contacts;
            item.ContactName = "Chan";
        }
    }
}

Output