Fixed bug in file loader.

Implemented ResetModified.

ucalc/Data/BillingLoader.cs

@@ -59,12 +59,12 @@ namespace UCalc.Data
         public override object ReadJson(JsonReader reader, Type objectType, object existingValue,
             JsonSerializer serializer)
         {
-            return existingValue ?? string.Empty;
+            return reader.Value ?? "";
         }
 
         public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
         {
-            writer.WriteValue(value ?? string.Empty);
+            writer.WriteValue(value ?? "");
         }
     }
 

ucalc/Models/Model.cs

@@ -248,7 +248,9 @@ namespace UCalc.Models
 
         public void ResetModified()
         {
-            throw new NotImplementedException();
+            using var validator = BeginValidation();
+
+            Root.ResetModified();
         }
 
         public event PropertyChangedEventHandler PropertyChanged;

ucalc/Models/Properties.cs

@@ -81,6 +81,11 @@ namespace UCalc.Models
 
             return i;
         }
+
+        public virtual void ResetModified()
+        {
+            Modified = false;
+        }
     }
 
     public abstract class ValueProperty<T> : Property
@@ -244,6 +249,14 @@ namespace UCalc.Models
 
             base.OnPropertyChanged(propertyName);
         }
+
+        public override void ResetModified()
+        {
+            foreach (var property in _properties)
+            {
+                property.ResetModified();
+            }
+        }
     }
 
     public abstract class MultiProperty<T> : Property, IReadOnlyList<T>, INotifyCollectionChanged where T : Property
@@ -342,6 +355,14 @@ namespace UCalc.Models
             base.OnPropertyChanged(propertyName);
         }
 
+        public override void ResetModified()
+        {
+            foreach (var property in _properties)
+            {
+                property.ResetModified();
+            }
+        }
+
         public IEnumerator<T> GetEnumerator()
         {
             return _properties.GetEnumerator();