fixes the estimate line edition

BookAStar/BookAStar/Converters/EnumConverter.cs

@@ -0,0 +1,22 @@
+using System;
+using System.Globalization;
+using Xamarin.Forms;
+
+namespace BookAStar.Converters
+{
+    /// <summary>
+    /// When EnumType:int
+    /// </summary>
+    class EnumConverter : IValueConverter
+    {
+        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
+        {
+            return value.ToString();
+        }
+
+        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
+        {
+            return (int) value;
+        }
+    }
+}