- Added non KVO dependent iOS specific, extendable ICreatesObservable…

…ForProperty implementation supporting some core UIKit controls

- Added MonoTouch Linker XML definition file that should be added to MonoTouch projects in release configuration. Otherwise the Monotouch Linker might optimize away properties referenced soley through ReactiveUI (reflection-driven) data-binding

ReactiveUI.Platforms/Cocoa/Buildsupport/Linker.xml

@@ -0,0 +1,40 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<linker>
+  <assembly fullname="monotouch">
+    <type fullname="MonoTouch.UIKit.UIControl" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UITextField" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UITextView" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UILabel" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UISlider" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UISearchBar" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UIButton" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UITableView" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UIActionSheet" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UIDatePicker" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UIView" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UIProgressView" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UISwitch" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UIActivityIndicatorView" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UIAlertView" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UIBarButtonItem" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UIBarItem" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UICollectionView" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UIScrollView" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UIImage" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UIImageView" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UINavigationBar" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UINavigationItem" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UIPageControl" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UIPickerView" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UIRefreshControl" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UISegmentedControl" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UIStepper" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UITabBar" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UITabBarItem" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UITableViewCell" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UIToolbar" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UITouch" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UIWebView" preserve="properties"></type>
+    <type fullname="MonoTouch.UIKit.UIWindow" preserve="properties"></type>
+  </assembly>
+</linker>

ReactiveUI.Platforms/Cocoa/UIKitObservableForProperty.cs

@@ -0,0 +1,37 @@
+using System;
+using ReactiveUI;
+using System.Collections.Generic;
+using MonoTouch.UIKit;
+using System.Linq;
+using MonoTouch.Foundation;
+using System.Reactive.Linq;
+using System.Runtime.InteropServices;
+using System.Reactive.Disposables;
+
+namespace ReactiveUI.Cocoa
+{
+	public class UIKitObservableForProperty : UIKitObservableForPropertyBase
+	{
+		public UIKitObservableForProperty ()
+		{
+			Register(typeof(UIControl), "Value", 9, (s, p)=> ObservableFromUIControlEvent(s, p, UIControlEvent.ValueChanged));
+
+			Register(typeof(UITextField), "Text", 10, (s, p) => ObservableFromNotification(s, p, UITextField.TextFieldTextDidChangeNotification));
+
+			Register(typeof(UIDatePicker), "Date",10,  (s, p)=> ObservableFromUIControlEvent(s, p, UIControlEvent.ValueChanged));
+
+			Register(typeof(UISegmentedControl), "SelectedSegment", 10, (s, p)=> ObservableFromUIControlEvent(s, p, UIControlEvent.ValueChanged));
+
+			Register(typeof(UISwitch), "On", 10, (s, p)=> ObservableFromUIControlEvent(s, p, UIControlEvent.ValueChanged));
+
+			Register(typeof(UISegmentedControl), "SelectedSegment", 10, (s, p)=> ObservableFromUIControlEvent(s, p, UIControlEvent.ValueChanged));
+
+			// Warning: This will stomp the Control's delegate
+			Register(typeof(UITabBar), "SelectedItem", 10, (s, p) => ObservableFromEvent(s, p, "ItemSelected"));
+
+			// Warning: This will stomp the Control's delegate
+			Register(typeof(UISearchBar), "Text", 10, (s, p) => ObservableFromEvent(s, p, "TextChanged"));
+		}
+	}
+}
+

ReactiveUI.Platforms/Cocoa/UIKitObservableForPropertyBase.cs

@@ -0,0 +1,155 @@
+using System;
+using ReactiveUI;
+using MonoTouch.Foundation;
+using MonoTouch.UIKit;
+using System.Reactive.Disposables;
+using System.Collections.Generic;
+using System.Linq;
+using System.Reactive.Linq;
+
+namespace ReactiveUI.Cocoa
+{
+	public abstract class UIKitObservableForPropertyBase :
+		ICreatesObservableForProperty
+	{
+		#region ICreatesObservableForProperty implementation
+
+		public int GetAffinityForObject(Type type, bool beforeChanged = false)
+		{
+			if(beforeChanged)
+				return 0;
+
+			var info = config.Keys
+				.Where(x=> x.IsAssignableFrom(type))
+				.Where(x=> config[x].Values.Any())
+				.Select(x=> config[x].Values.OrderByDescending(y=> y.Affinity).FirstOrDefault())
+				.OrderByDescending(x=> x.Affinity)
+				.FirstOrDefault();
+
+			if(info == null)
+				return 0;
+
+			return info.Affinity;
+		}
+
+		public IObservable<IObservedChange<object, object>> GetNotificationForProperty(object sender, string propertyName, bool beforeChanged = false)
+		{
+			var type = sender.GetType();
+
+			if(beforeChanged)
+				return Observable.Never<IObservedChange<object, object>>();
+
+			Dictionary<string, ObservablePropertyInfo> typeProperties;
+			if(!config.TryGetValue(type, out typeProperties))
+				throw new NotSupportedException(string.Format("Notifications for {0} are not supported", type.Name));
+
+			ObservablePropertyInfo info;
+			if(!typeProperties.TryGetValue(propertyName, out info))
+				throw new NotSupportedException(string.Format("Notifications for {0}.{1} are not supported", type.Name, propertyName));
+
+			return info.CreateObservable((NSObject) sender, propertyName);
+		}
+
+		#endregion
+
+		internal class ObservablePropertyInfo
+		{
+			public int Affinity;
+			public Func<NSObject, string, IObservable<IObservedChange<object, object>>> CreateObservable;
+		}
+
+		/// <summary>
+		/// Configuration map
+		/// </summary>
+		readonly Dictionary<Type, Dictionary<string, ObservablePropertyInfo>> config =
+			new Dictionary<Type, Dictionary<string, ObservablePropertyInfo>>();
+
+		/// <summary>
+		/// Registers an observable factory for the specified type and property.
+		/// </summary>
+		/// <param name="type">Type.</param>
+		/// <param name="property">Property.</param>
+		/// <param name="createObservable">Create observable.</param>
+		protected void Register(Type type, string property, int affinity, Func<NSObject, string, IObservable<IObservedChange<object, object>>> createObservable)
+		{
+			Dictionary<string, ObservablePropertyInfo> typeProperties;
+			if(!config.TryGetValue(type, out typeProperties))
+			{
+				typeProperties = new Dictionary<string, ObservablePropertyInfo>();
+				config[type] = typeProperties;
+			}
+
+			var info = new ObservablePropertyInfo { Affinity = affinity, CreateObservable = createObservable };
+			typeProperties[property] = info;
+		}
+
+		/// <summary>
+		/// Creates an Observable for a UIControl Event
+		/// </summary>
+		/// <returns>An observable</returns>
+		/// <param name="sender">The sender</param>
+		/// <param name="propertyName">The property name </param>
+		/// <param name="evt">The control event to listen for</param>
+		protected static IObservable<IObservedChange<object, object>> ObservableFromUIControlEvent(NSObject sender, string propertyName, UIControlEvent evt)
+		{
+			return Observable.Create<IObservedChange<object, object>>(subj =>
+			{
+				var control = (UIControl) sender;
+
+				EventHandler handler = (s,e)=>
+				{
+					subj.OnNext(new ObservedChange<object, object>() { Sender = sender, PropertyName = propertyName });
+				};
+
+				control.AddTarget(handler, evt);
+
+				return Disposable.Create(() =>
+				{
+					control.RemoveTarget(handler, evt);
+				});
+			});
+		}
+
+		/// <summary>
+		/// Creates an Observable for a NSNotificationCenter notification
+		/// </summary>
+		/// <returns>The from notification.</returns>
+		/// <param name="sender">Sender.</param>
+		/// <param name="propertyName">Property name.</param>
+		/// <param name="notification">Notification.</param>
+		protected static IObservable<IObservedChange<object, object>> ObservableFromNotification(NSObject sender, string propertyName, NSString notification)
+		{
+			return Observable.Create<IObservedChange<object, object>>(subj =>
+			{
+				var handle = NSNotificationCenter.DefaultCenter.AddObserver (notification, (e)=>
+				{
+					subj.OnNext(new ObservedChange<object, object>() { Sender = sender, PropertyName = propertyName });
+				}, sender);
+
+				return Disposable.Create(() =>
+				{
+					NSNotificationCenter.DefaultCenter.RemoveObserver(handle);
+				});
+			});
+		}
+
+		/// <summary>
+		/// Creates an Observable for a NSNotificationCenter notification
+		/// </summary>
+		/// <returns>The from notification.</returns>
+		/// <param name="sender">Sender.</param>
+		/// <param name="propertyName">Property name.</param>
+		/// <param name="notification">Notification.</param>
+		protected static IObservable<IObservedChange<object, object>> ObservableFromEvent(NSObject sender, string propertyName, string eventName)
+		{
+			return Observable.Create<IObservedChange<object, object>>(subj =>
+			{
+				return Observable.FromEventPattern(sender, eventName).Subscribe((e) =>
+				{
+					subj.OnNext(new ObservedChange<object, object>() { Sender = sender, PropertyName = propertyName });
+				});
+			});
+		}
+	}
+}
+

ReactiveUI.Platforms/ReactiveUI.Cocoa_Monotouch.csproj

@@ -71,6 +71,8 @@
     <Compile Include="PlatformUnitTestDetector.cs" />
     <Compile Include="Registrations.cs" />
     <Compile Include="Cocoa\PlatformOperations.cs" />
+    <Compile Include="Cocoa\UIKitObservableForProperty.cs" />
+    <Compile Include="Cocoa\UIKitObservableForPropertyBase.cs" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\ReactiveUI\ReactiveUI_Monotouch.csproj">

ReactiveUI.Platforms/Registrations.cs

@@ -52,7 +52,8 @@ public void Register(Action<Func<object>, Type> registerFunction)
 #endif
 
 #if COCOA
-            registerFunction(() => new KVOObservableForProperty(), typeof(ICreatesObservableForProperty));
+			registerFunction(() => new UIKitObservableForProperty(), typeof(ICreatesObservableForProperty));
+			registerFunction(() => new KVOObservableForProperty(), typeof(ICreatesObservableForProperty));
             registerFunction(() => new CocoaDefaultPropertyBinding(), typeof(IDefaultPropertyBindingProvider));
             registerFunction(() => new TargetActionCommandBinder(), typeof(ICreatesCommandBinding));
 #endif

ReactiveUI/RxApp.cs

@@ -41,7 +41,7 @@ public static class RxApp
     {
         public static void Initialize()
         {
-            _TaskpoolScheduler = Scheduler.TaskPool;
+			_TaskpoolScheduler = TaskPoolScheduler.Default;
 
             DefaultExceptionHandler = Observer.Create<Exception>(ex => {
                 // NB: If you're seeing this, it means that an