项目更改时更新WPF列表

public class MyViewModel : INotifyPropertyChanged
{
    private ObservableCollection<string> _items;

    public ObservableCollection<string> Items
    {
        get { return _items; }
        set
        {
            _items = value;
            OnPropertyChanged("Items");
        }
    }

    public MyViewModel()
    {
        _items = new ObservableCollection<string>();
    }

    public event PropertyChangedEventHandler PropertyChanged;

    protected virtual void OnPropertyChanged(string propertyName)
    {
        PropertyChangedEventHandler handler = PropertyChanged;
        if (handler != null) handler(this, new PropertyChangedEventArgs(propertyName));
    }
}

        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:MyApp"
        mc:Ignorable="d"
        Title="MainWindow" Height="350" Width="525">
   <Window.DataContext>
       <local:MyViewModel />
    </Window.DataContext>
    <Grid>
       <ListView ItemsSource="{Binding Items}">
           <ListView.View>
               <GridView>
                   <GridViewColumn Header="Item" DisplayMemberBinding="{Binding}" />
                </GridView>
            </ListView.View>
        </ListView>
    </Grid>
</Window>

((MyViewModel)DataContext).Items.Add("New item");