Fixed some stuff, added an ICreatesObservableForProperty for WinForms

Author: anaisbetts

ReactiveUI.Platforms/PlatformUnitTestDetector.cs

@@ -10,7 +10,11 @@
 using Windows.ApplicationModel;
 #endif
 
+#if WINFORMS
+namespace ReactiveUI.Winforms
+#else
 namespace ReactiveUI
+#endif
 {
     /// <summary>
     /// Because RxUI.dll is in a PLib, it doesn't have the SuperPowers it needs

ReactiveUI.Platforms/ReactiveUI.Winforms_Net45.csproj

@@ -31,7 +31,7 @@
     <DebugType>full</DebugType>
     <Optimize>false</Optimize>
     <OutputPath>bin\Debug\Net45\</OutputPath>
-    <DefineConstants>DEBUG;TRACE;NET_45</DefineConstants>
+    <DefineConstants>TRACE;DEBUG;WINFORMS</DefineConstants>
     <ErrorReport>prompt</ErrorReport>
     <WarningLevel>4</WarningLevel>
     <CodeContractsEnableRuntimeChecking>False</CodeContractsEnableRuntimeChecking>
@@ -65,7 +65,7 @@
     <DebugType>pdbonly</DebugType>
     <Optimize>true</Optimize>
     <OutputPath>bin\Release\Net45\</OutputPath>
-    <DefineConstants>TRACE;NET_45</DefineConstants>
+    <DefineConstants>TRACE;WINFORMS</DefineConstants>
     <ErrorReport>prompt</ErrorReport>
     <WarningLevel>4</WarningLevel>
     <CodeContractsEnableRuntimeChecking>False</CodeContractsEnableRuntimeChecking>
@@ -123,12 +123,13 @@
   </ItemGroup>
   <ItemGroup>
     <Compile Include="ComponentModelTypeConverter.cs" />
+    <Compile Include="PlatformUnitTestDetector.cs" />
     <Compile Include="Winforms\ReactiveBindingList.cs" />
     <Compile Include="Winforms\CreatesCommandBinding.cs" />
     <Compile Include="Winforms\PlatformOperations.cs" />
-    <Compile Include="Winforms\PlatformUnitTestDetector.cs" />
     <Compile Include="Winforms\Properties\AssemblyInfo.cs" />
     <Compile Include="Winforms\Registrations.cs" />
+    <Compile Include="Winforms\WinformsCreatesObservableForProperty.cs" />
     <Compile Include="Winforms\WinformsDefaultPropertyBinding.cs" />
   </ItemGroup>
   <ItemGroup>

ReactiveUI.Platforms/Winforms/PlatformUnitTestDetector.cs

@@ -7,12 +7,10 @@
 using System.Windows;
 using ReactiveUI;
 using System.Reactive.Concurrency;
-
+using System.Windows.Forms;
 
 namespace ReactiveUI.Winforms
 {
-    using System.Windows.Forms;
-
     /// <summary>
     /// Ignore me. This class is a secret handshake between RxUI and RxUI.Xaml
     /// in order to register certain classes on startup that would be difficult
@@ -28,7 +26,7 @@ public void Register(Action<Func<object>, Type> registerFunction)
 
             registerFunction(() => new WinformsDefaultPropertyBinding(), typeof(IDefaultPropertyBindingProvider));
             registerFunction(() => new CreatesWinformsCommandBinding(), typeof(ICreatesCommandBinding));
-         
+            registerFunction(() => new WinformsCreatesObservableForProperty(), typeof(ICreatesObservableForProperty));
 
             RxApp.InUnitTestRunnerOverride = PlatformUnitTestDetector.InUnitTestRunner();
             if (RxApp.InUnitTestRunner()) {
@@ -37,7 +35,6 @@ public void Register(Action<Func<object>, Type> registerFunction)
 
             WindowsFormsSynchronizationContext.AutoInstall = true;
             RxApp.MainThreadScheduler = new WaitForDispatcherScheduler(() => new SynchronizationContextScheduler(new WindowsFormsSynchronizationContext()));
-
         }
     }
 }

ReactiveUI.Platforms/Winforms/Registrations.cs

@@ -0,0 +1,56 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Reactive.Disposables;
+using System.Reactive.Linq;
+using System.Reflection;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace ReactiveUI.Winforms
+{
+    public class WinformsCreatesObservableForProperty : ICreatesObservableForProperty
+    {
+        static readonly MemoizingMRUCache<Tuple<Type, string>, EventInfo> eventInfoCache = new MemoizingMRUCache<Tuple<Type, string>, EventInfo>((pair, _) => {
+            return pair.Item1.GetEvents(System.Reflection.BindingFlags.FlattenHierarchy | System.Reflection.BindingFlags.Instance | System.Reflection.BindingFlags.Public)
+                .FirstOrDefault(x => x.Name == pair.Item2 + "Changed");
+        }, RxApp.SmallCacheLimit);
+
+        public int GetAffinityForObject(Type type, string propertyName, bool beforeChanged = false)
+        {
+            if (!type.FullName.ToLowerInvariant().StartsWith("system.windows.forms")) return 0;
+
+            lock (eventInfoCache) {
+                var ei = eventInfoCache.Get(Tuple.Create(type, propertyName));
+                return (beforeChanged == false && ei != null) ?  8 : 0;
+            }
+        }
+
+        public IObservable<IObservedChange<object, object>> GetNotificationForProperty(object sender, string propertyName, bool beforeChanged = false)
+        {
+            var type = sender.GetType();
+            var ei = default(EventInfo);
+            var getter = Reflection.GetValueFetcherOrThrow(type, propertyName);
+
+            lock (eventInfoCache) {
+                ei = eventInfoCache.Get(Tuple.Create(type, propertyName));
+            }
+
+            return Observable.Create<IObservedChange<object, object>>(subj => {
+                bool completed = false;
+                var handler = new EventHandler((o, e) => {
+                    if (completed) return;
+                    try {
+                        subj.OnNext(new ObservedChange<object, object>() { Sender = sender, PropertyName = propertyName, Value = getter(sender) });
+                    } catch (Exception ex) {
+                        subj.OnError(ex);
+                        completed = true;
+                    }
+                });
+
+                ei.AddEventHandler(sender, handler);
+                return Disposable.Create(() => ei.RemoveEventHandler(sender, handler));
+            });
+        }
+    }
+}

ReactiveUI.Platforms/Winforms/WinformsCreatesObservableForProperty.cs

@@ -114,7 +114,9 @@
     <Compile Include="Winforms\CommandBindingTests.cs">
       <SubType>Component</SubType>
     </Compile>
-    <Compile Include="Winforms\DefaultPropertyBindingTests.cs" />
+    <Compile Include="Winforms\DefaultPropertyBindingTests.cs">
+      <SubType>Component</SubType>
+    </Compile>
     <Compile Include="Winforms\ReactiveBindingListTests.cs" />
     <Compile Include="Xaml\DependencyObjectObservableForPropertyTest.cs" />
     <Compile Include="ErrorsTest.cs" />
@@ -147,7 +149,7 @@
       <Name>ReactiveUI.NLog_Net45</Name>
     </ProjectReference>
     <ProjectReference Include="..\ReactiveUI.Platforms\ReactiveUI.Winforms_Net45.csproj">
-      <Project>{F5ECBDE5-E525-4482-B568-63217BCB0A0B}</Project>
+      <Project>{f5ecbde5-e525-4482-b568-63217bcb0a0b}</Project>
       <Name>ReactiveUI.Winforms_Net45</Name>
     </ProjectReference>
     <ProjectReference Include="..\ReactiveUI.Testing\ReactiveUI.Testing_Net45.csproj">