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diff --git a/Xamarin.Forms.Platform.WinRT/AsyncValue.cs b/Xamarin.Forms.Platform.WinRT/AsyncValue.cs
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+//
+// AsyncValue.cs
+//
+// Author:
+// Eric Maupin <me@ermau.com>
+//
+// Copyright (c) 2013-2014 Xamarin, Inc.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+using System;
+using System.ComponentModel;
+using System.Runtime.CompilerServices;
+using System.Threading;
+using System.Threading.Tasks;
+
+#if WINDOWS_UWP
+
+namespace Xamarin.Forms.Platform.UWP
+#else
+
+namespace Xamarin.Forms.Platform.WinRT
+#endif
+{
+ internal sealed class AsyncValue<T> : INotifyPropertyChanged
+ {
+ readonly T _defaultValue;
+ readonly Task<T> _valueTask;
+ bool _isRunning = true;
+
+ public AsyncValue(Task<T> valueTask, T defaultValue)
+ {
+ if (valueTask == null)
+ throw new ArgumentNullException("valueTask");
+
+ _valueTask = valueTask;
+ _defaultValue = defaultValue;
+
+ TaskScheduler scheduler = TaskScheduler.FromCurrentSynchronizationContext();
+
+ _valueTask.ContinueWith(t => { IsRunning = false; }, scheduler);
+
+ _valueTask.ContinueWith(t => { OnPropertyChanged("Value"); }, CancellationToken.None, TaskContinuationOptions.OnlyOnRanToCompletion, scheduler);
+ }
+
+ public bool IsRunning
+ {
+ get { return _isRunning; }
+ set
+ {
+ if (_isRunning == value)
+ return;
+
+ _isRunning = value;
+ OnPropertyChanged();
+ }
+ }
+
+ public T Value
+ {
+ get
+ {
+ if (_valueTask.Status != TaskStatus.RanToCompletion)
+ return _defaultValue;
+
+ return _valueTask.Result;
+ }
+ }
+
+ public event PropertyChangedEventHandler PropertyChanged;
+
+ void OnPropertyChanged([CallerMemberName] string propertyName = null)
+ {
+ PropertyChangedEventHandler handler = PropertyChanged;
+ if (handler != null)
+ handler(this, new PropertyChangedEventArgs(propertyName));
+ }
+ }
+} \ No newline at end of file