public override Task OnNavigatedToAsync(object parameter, NavigationMode mode, IDictionary<string, object> state) { Messenger.Default.Send(new NotificationMessage<string>("Reset_Listview", "Reset")); Messenger.Default.Register<WidthMessage>(this, (message) => { var m = message.Width; this.ItemWidth = m; }); return base.OnNavigatedToAsync(parameter, mode, state); }