未为wpf TextBox正确更新UI

public class ViewModel : INotifyPropertyChanged
{
    private string _text;

    public string Text
    {
        get { return _text; }
        set
        {
            if (_text != value)
            {
                _text = value;
                OnPropertyChanged(nameof(Text));
            }
        }
    }

    public event PropertyChangedEventHandler PropertyChanged;

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

<Window x:Class="YourNamespace.YourWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:local="clr-namespace:YourNamespace"
        Title="Your Window" Height="450" Width="800">
    <Window.DataContext>
        <local:ViewModel />
    </Window.DataContext>
    
    <Grid>
        <TextBox Text="{Binding Text}" />
    </Grid>
</Window>

private void UpdateTextButton_Click(object sender, RoutedEventArgs e)
{
    ViewModel.Text = "New Text";
}