using System; using Xamarin.Forms; using System.Globalization; namespace TripExpenses.UI { public class MultiTriggerConverter : IValueConverter { public object Convert(object value, Type targetType, object parameter, CultureInfo culture) { if ((int)value > 0) // length > 0 ? return true; // some data has been entered else return false; // input is empty } public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture) { throw new NotSupportedException (); } } }