to be tested

BookAStar/BookAStar/Helpers/ObservableString.cs

@@ -0,0 +1,59 @@
+using System;
+using System.Collections.Generic;
+
+namespace BookAStar
+{
+    public class ObservableString : IObservable<string>, IDisposable
+    {
+        public ObservableString(string data)
+        {
+            this.data = data;
+        }
+        private string data = null;
+        private List<IObserver<string>> observers = new List<IObserver<string>>();
+
+        public string Data
+        {
+            get
+            {
+                return data;
+            }
+
+            set
+            {
+                if (data != value)
+                {
+                    data = value;
+                    foreach (var obs in observers)
+                        obs.OnCompleted();
+                }
+            }
+        }
+
+        public override string ToString()
+        {
+            return data;
+        }
+
+        public static explicit operator ObservableString  (string data)
+        {
+            return new ObservableString(data);
+        }
+
+        public static explicit operator string (ObservableString observable)
+        {
+            return observable.ToString();
+        }
+
+        public void Dispose()
+        {
+            observers = null;
+        }
+
+        public IDisposable Subscribe(IObserver<string> observer)
+        {
+            observers.Add(observer);
+            return this;
+        }
+    }
+}