xamarin.forms更改可观察集合的属性不会更新UI

using System.Collections.ObjectModel;
using System.ComponentModel;
using Xamarin.Forms;

public class Item : INotifyPropertyChanged
{
    private string name;
    public string Name
    {
        get { return name; }
        set
        {
            if (name != value)
            {
                name = value;
                OnPropertyChanged("Name");
            }
        }
    }

    public event PropertyChangedEventHandler PropertyChanged;

    protected virtual void OnPropertyChanged(string propertyName)
    {
        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
    }
}

public class ViewModel
{
    public ObservableCollection<Item> Items { get; set; }

    public ViewModel()
    {
        Items = new ObservableCollection<Item>
        {
            new Item { Name = "Item 1" },
            new Item { Name = "Item 2" },
            new Item { Name = "Item 3" }
        };
    }

    public void ChangeItemName()
    {
        Items[0].Name = "New Name"; // 更改可观察集合的属性
    }
}

public class MainPage : ContentPage
{
    public MainPage()
    {
        var viewModel = new ViewModel();

        var listView = new ListView
        {
            ItemsSource = viewModel.Items,
            ItemTemplate = new DataTemplate(() =>
            {
                var nameLabel = new Label();
                nameLabel.SetBinding(Label.TextProperty, "Name");
                return new ViewCell { View = nameLabel };
            })
        };

        var button = new Button
        {
            Text = "Change Name",
            Command = new Command(() => viewModel.ChangeItemName())
        };

        Content = new StackLayout
        {
            Children = { listView, button }
        };
    }
}