FeedbackFormView.xaml.cs

public sealed partial class FeedbackView : Page, IViewFor<FeedbackViewModel>
{
    public static readonly DependencyProperty ViewModelProperty = DependencyProperty
           .Register(nameof(ViewModel), typeof(FeedbackViewModel), typeof(FeedbackView), null);

    public FeedbackView()
    {
        InitializeComponent();
        ViewModel = new FeedbackViewModel(new UwpSender(), new Clock());
        this.WhenActivated(disposables => { /* handle interactions, etc. */ });
    }

    public FeedbackViewModel ViewModel
    {
        get => (FeedbackViewModel)GetValue(ViewModelProperty);
        set => SetValue(ViewModelProperty, value);
    }

    object IViewFor.ViewModel
    {
        get => ViewModel;
        set => ViewModel = (FeedbackViewModel)value;
    }
}