[iOS] Keep our native property listener around the same time we keep our proxy, check if we are KVO compliant before adding observer (#403)

2 files changed, 50 insertions, 15 deletions

diff --git a/Xamarin.Forms.ControlGallery.iOS/AppDelegate.cs b/Xamarin.Forms.ControlGallery.iOS/AppDelegate.cs
index 3eb36bfc..71c5e0c6 100644
--- a/Xamarin.Forms.ControlGallery.iOS/AppDelegate.cs
+++ b/Xamarin.Forms.ControlGallery.iOS/AppDelegate.cs
@@ -156,7 +156,7 @@ namespace Xamarin.Forms.ControlGallery.iOS
 			MessagingCenter.Subscribe<Bugzilla40911>(this, Bugzilla40911.ReadyToSetUp40911Test, SetUp40911Test);
 
 			// When the native binding gallery loads up, it'll let us know so we can set up the native bindings
-			MessagingCenter.Subscribe<NativeBindingGalleryPage >(this, NativeBindingGalleryPage.ReadyForNativeBindingsMessage, AddNativeBindings);
+			MessagingCenter.Subscribe<NativeBindingGalleryPage>(this, NativeBindingGalleryPage.ReadyForNativeBindingsMessage, AddNativeBindings);
 
 			LoadApplication(app);
 			return base.FinishedLaunching(uiApplication, launchOptions);
@@ -297,6 +297,12 @@ namespace Xamarin.Forms.ControlGallery.iOS
 			uilabel.SetBinding("Text", new Binding("NativeLabel"));
 			uilabel.SetBinding(nameof(uilabel.TextColor), new Binding("NativeLabelColor", converter: nativeColorConverter));
 
+			var kvoSlider = new KVOUISlider();
+			kvoSlider.MaxValue = 100;
+			kvoSlider.MinValue = 0;
+			kvoSlider.SetBinding(nameof(kvoSlider.KVOValue), new Binding("Age", BindingMode.TwoWay));
+			sl?.Children.Add(kvoSlider);
+
 			var uiView = new UIView(new RectangleF(0, 0, width, heightCustomLabelView));
 			uiView.Add(uilabel);
 			sl?.Children.Add(uiView);
@@ -321,32 +327,61 @@ namespace Xamarin.Forms.ControlGallery.iOS
 			page.Layout.Children.Add(button);
 		}
 
-		public void StartPressed40911 ()
-        {
+		public void StartPressed40911()
+		{
 			var loginViewController = new UIViewController { View = { BackgroundColor = UIColor.White } };
-			var button = UIButton.FromType (UIButtonType.RoundedRect);
-            button.SetTitle ("Login", UIControlState.Normal);
-            button.Frame = new CGRect (20, 100, 200, 44);
-            loginViewController.View.AddSubview (button);
-
-            button.TouchUpInside += (sender, e) => {
-                Xamarin.Forms.Application.Current.MainPage = new ContentPage {Content = new Label {Text = "40911 Success"} };
-                loginViewController.DismissViewController (true, null);
+			var button = UIButton.FromType(UIButtonType.RoundedRect);
+			button.SetTitle("Login", UIControlState.Normal);
+			button.Frame = new CGRect(20, 100, 200, 44);
+			loginViewController.View.AddSubview(button);
+
+			button.TouchUpInside += (sender, e) =>
+			{
+				Xamarin.Forms.Application.Current.MainPage = new ContentPage { Content = new Label { Text = "40911 Success" } };
+				loginViewController.DismissViewController(true, null);
 			};
 
-			var window= UIApplication.SharedApplication.KeyWindow;
+			var window = UIApplication.SharedApplication.KeyWindow;
 			var vc = window.RootViewController;
 			while (vc.PresentedViewController != null)
 			{
 				vc = vc.PresentedViewController;
 			}
 
-            vc.PresentViewController (loginViewController, true, null);
+			vc.PresentViewController(loginViewController, true, null);
 		}
 
 		#endregion
 	}
 
+	[Register("KVOUISlider")]
+	public class KVOUISlider : UISlider
+	{
+
+		public KVOUISlider()
+		{
+			ValueChanged += (s, e) => KVOValue = Value;
+		}
+
+		float _kVOValue;
+		[Export("kvovalue")]
+		public float KVOValue
+		{
+			get
+			{
+
+				return _kVOValue;
+			}
+			set
+			{
+
+				WillChangeValue(nameof(KVOValue).ToLower());
+				_kVOValue = Value = value;
+				DidChangeValue(nameof(KVOValue).ToLower());
+			}
+		}
+	}
+
 	public class ColorConverter : IValueConverter
 	{
 		public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
diff --git a/Xamarin.Forms.ControlGallery.iOS/Xamarin.Forms.ControlGallery.iOS.csproj b/Xamarin.Forms.ControlGallery.iOS/Xamarin.Forms.ControlGallery.iOS.csproj
index c1ef6f4c..9af0106a 100644
--- a/Xamarin.Forms.ControlGallery.iOS/Xamarin.Forms.ControlGallery.iOS.csproj
+++ b/Xamarin.Forms.ControlGallery.iOS/Xamarin.Forms.ControlGallery.iOS.csproj
@@ -24,7 +24,7 @@
     <WarningLevel>4</WarningLevel>
     <ConsolePause>false</ConsolePause>
     <MtouchArch>i386, x86_64</MtouchArch>
-    <MtouchLink>SdkOnly</MtouchLink>
+    <MtouchLink>None</MtouchLink>
     <MtouchDebug>True</MtouchDebug>
     <CodesignEntitlements>Entitlements.plist</CodesignEntitlements>
     <MtouchSdkVersion></MtouchSdkVersion>
@@ -268,4 +268,4 @@
     </XamarinComponentReference>
   </ItemGroup>
   <Import Project="..\packages\Xamarin.Insights.1.12.3\build\Xamarin.iOS10\Xamarin.Insights.targets" Condition="Exists('..\packages\Xamarin.Insights.1.12.3\build\Xamarin.iOS10\Xamarin.Insights.targets')" />
-</Project>
\ No newline at end of file
+</Project>