[Xaml] support native views and native bindings (#266)

Allows including Native views directly in xaml.
Support for ios, android, UWP

5 files changed, 339 insertions, 2 deletions

diff --git a/Xamarin.Forms.Xaml.UnitTests/Issues/BPNotResolvedOnSubClass.xaml.cs b/Xamarin.Forms.Xaml.UnitTests/Issues/BPNotResolvedOnSubClass.xaml.cs
index 65bb73f1..c6913949 100644
--- a/Xamarin.Forms.Xaml.UnitTests/Issues/BPNotResolvedOnSubClass.xaml.cs
+++ b/Xamarin.Forms.Xaml.UnitTests/Issues/BPNotResolvedOnSubClass.xaml.cs
@@ -3,6 +3,7 @@ using System.Collections.Generic;
 
 using Xamarin.Forms;
 using NUnit.Framework;
+using Xamarin.Forms.Core.UnitTests;
 
 namespace Xamarin.Forms.Xaml.UnitTests
 {
@@ -29,6 +30,18 @@ namespace Xamarin.Forms.Xaml.UnitTests
 		[TestFixture]
 		class Tests
 		{
+			[SetUp]
+			public void Setup()
+			{
+				Device.PlatformServices = new MockPlatformServices();
+			}
+
+			[TearDown]
+			public void TearDown()
+			{
+				Device.PlatformServices = null;
+			}
+
 			[TestCase(true)]
 			[TestCase(false)]
 			public void CorrectlyResolveBPOnSubClasses (bool useCompiledXaml)
diff --git a/Xamarin.Forms.Xaml.UnitTests/Issues/Issue1497.cs b/Xamarin.Forms.Xaml.UnitTests/Issues/Issue1497.cs
index 3813f73a..b35339d5 100644
--- a/Xamarin.Forms.Xaml.UnitTests/Issues/Issue1497.cs
+++ b/Xamarin.Forms.Xaml.UnitTests/Issues/Issue1497.cs
@@ -1,11 +1,24 @@
 using System;
 using NUnit.Framework;
+using Xamarin.Forms.Core.UnitTests;
 
 namespace Xamarin.Forms.Xaml.UnitTests
 {
 	[TestFixture]
 	public class Issue1497
 	{
+		[SetUp]
+		public void Setup()
+		{
+			Device.PlatformServices = new MockPlatformServices();
+		}
+
+		[TearDown]
+		public void TearDown()
+		{
+			Device.PlatformServices = null;
+		}
+
 		[Test]
 		public void BPCollectionsWithSingleElement ()
 		{
@@ -23,5 +36,4 @@ namespace Xamarin.Forms.Xaml.UnitTests
 			Assert.True (grid.ColumnDefinitions [0].Width.IsStar);
 		}
 	}
-}
-
+}
\ No newline at end of file
diff --git a/Xamarin.Forms.Xaml.UnitTests/NativeViewsAndBindings.xaml b/Xamarin.Forms.Xaml.UnitTests/NativeViewsAndBindings.xaml
new file mode 100644
index 00000000..a35f8e50
--- /dev/null
+++ b/Xamarin.Forms.Xaml.UnitTests/NativeViewsAndBindings.xaml
@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
+		xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
+		xmlns:ios="clr-namespace:Xamarin.Forms.Xaml.UnitTests;targetPlatform=iOS"
+		xmlns:android="clr-namespace:Xamarin.Forms.Xaml.UnitTests;targetPlatform=Android"
+		x:Class="Xamarin.Forms.Xaml.UnitTests.NativeViewsAndBindings">
+	<StackLayout>
+		<ContentView x:Name="view0">
+			<ios:MockUIView Foo="foo" Bar="42" Baz="{Binding Baz}" View.HorizontalOptions="End" View.VerticalOptions="{Binding VerticalOption}" />
+			<android:MockAndroidView Foo="foo" Bar="42" Baz="{Binding Baz}" View.HorizontalOptions="End" View.VerticalOptions="{Binding VerticalOption}" />
+		</ContentView>
+	</StackLayout>
+</ContentPage>
\ No newline at end of file
diff --git a/Xamarin.Forms.Xaml.UnitTests/NativeViewsAndBindings.xaml.cs b/Xamarin.Forms.Xaml.UnitTests/NativeViewsAndBindings.xaml.cs
new file mode 100644
index 00000000..ce02d63b
--- /dev/null
+++ b/Xamarin.Forms.Xaml.UnitTests/NativeViewsAndBindings.xaml.cs
@@ -0,0 +1,293 @@
+using System;
+using System.Collections.Generic;
+using System.ComponentModel;
+using NUnit.Framework;
+using Xamarin.Forms;
+using Xamarin.Forms.Core.UnitTests;
+
+namespace Xamarin.Forms.Xaml.UnitTests
+{
+	public abstract class MockNativeView
+	{ 
+		public string Foo { get; set; }
+		public int Bar { get; set; }
+		public string Baz { get; set; }
+	}
+
+	public class MockUIView : MockNativeView
+	{
+		public IList<MockUIView> SubViews { get; set; }
+	}
+
+	class MockUIViewWrapper : View
+	{
+		public MockUIView NativeView { get; }
+
+		public MockUIViewWrapper(MockUIView nativeView)
+		{
+			NativeView = nativeView;
+			nativeView.TransferbindablePropertiesToWrapper(this);
+		}
+
+		protected override void OnBindingContextChanged()
+		{
+			NativeView.SetBindingContext(BindingContext, nv => nv.SubViews);
+			base.OnBindingContextChanged();
+		}
+	}
+
+	public class MockAndroidView : MockNativeView
+	{
+		public IList<MockAndroidView> SubViews { get; set; }
+	}
+
+	class MockAndroidViewWrapper : View
+	{
+		public MockAndroidView NativeView { get; }
+
+		public MockAndroidViewWrapper(MockAndroidView nativeView)
+		{
+			NativeView = nativeView;
+			nativeView.TransferbindablePropertiesToWrapper(this);
+		}
+
+		protected override void OnBindingContextChanged()
+		{
+			NativeView.SetBindingContext(BindingContext, nv => nv.SubViews);
+			base.OnBindingContextChanged();
+		}
+	}
+
+	public static class MockNativeViewExtensions
+	{
+		public static View ToView(this MockUIView nativeView)
+		{
+			return new MockUIViewWrapper(nativeView);
+		}
+
+		public static void SetBinding(this MockUIView target, string targetProperty, BindingBase binding, string updateSourceEventName = null)
+		{
+			NativeBindingHelpers.SetBinding(target, targetProperty, binding, updateSourceEventName);
+		}
+
+		internal static void SetBinding(this MockUIView target, string targetProperty, BindingBase binding, INotifyPropertyChanged propertyChanged)
+		{
+			NativeBindingHelpers.SetBinding(target, targetProperty, binding, propertyChanged);
+		}
+
+		public static void SetBinding(this MockUIView target, BindableProperty targetProperty, BindingBase binding)
+		{
+			NativeBindingHelpers.SetBinding(target, targetProperty, binding);
+		}
+
+		public static void SetValue(this MockUIView target, BindableProperty targetProperty, object value)
+		{
+			NativeBindingHelpers.SetValue(target, targetProperty, value);
+		}
+
+		public static void SetBindingContext(this MockUIView target, object bindingContext, Func<MockUIView, IEnumerable<MockUIView>> getChild = null)
+		{
+			NativeBindingHelpers.SetBindingContext(target, bindingContext, getChild);
+		}
+
+		internal static void TransferbindablePropertiesToWrapper(this MockUIView target, MockUIViewWrapper wrapper)
+		{
+			NativeBindingHelpers.TransferBindablePropertiesToWrapper(target, wrapper);
+		}
+
+		public static View ToView(this MockAndroidView nativeView)
+		{
+			return new MockAndroidViewWrapper(nativeView);
+		}
+
+		public static void SetBinding(this MockAndroidView target, string targetProperty, BindingBase binding, string updateSourceEventName = null)
+		{
+			NativeBindingHelpers.SetBinding(target, targetProperty, binding, updateSourceEventName);
+		}
+
+		internal static void SetBinding(this MockAndroidView target, string targetProperty, BindingBase binding, INotifyPropertyChanged propertyChanged)
+		{
+			NativeBindingHelpers.SetBinding(target, targetProperty, binding, propertyChanged);
+		}
+
+		public static void SetBinding(this MockAndroidView target, BindableProperty targetProperty, BindingBase binding)
+		{
+			NativeBindingHelpers.SetBinding(target, targetProperty, binding);
+		}
+
+		public static void SetValue(this MockAndroidView target, BindableProperty targetProperty, object value)
+		{
+			NativeBindingHelpers.SetValue(target, targetProperty, value);
+		}
+
+		public static void SetBindingContext(this MockAndroidView target, object bindingContext, Func<MockAndroidView, IEnumerable<MockAndroidView>> getChild = null)
+		{
+			NativeBindingHelpers.SetBindingContext(target, bindingContext, getChild);
+		}
+
+		internal static void TransferbindablePropertiesToWrapper(this MockAndroidView target, MockAndroidViewWrapper wrapper)
+		{
+			NativeBindingHelpers.TransferBindablePropertiesToWrapper(target, wrapper);
+		}
+	}
+
+	public class MockIosNativeValueConverterService : INativeValueConverterService
+	{
+		public bool ConvertTo(object value, Type toType, out object nativeValue)
+		{
+			nativeValue = null;
+			if (typeof(MockUIView).IsInstanceOfType(value) && toType.IsAssignableFrom(typeof(View))) {
+				nativeValue = ((MockUIView)value).ToView();
+				return true;
+			}
+			return false;
+		}
+	}
+
+	public class MockAndroidNativeValueConverterService : INativeValueConverterService
+	{
+		public bool ConvertTo(object value, Type toType, out object nativeValue)
+		{
+			nativeValue = null;
+			if (typeof(MockAndroidView).IsInstanceOfType(value) && toType.IsAssignableFrom(typeof(View))) {
+				nativeValue = ((MockAndroidView)value).ToView();
+				return true;
+			}
+			return false;
+		}
+	}
+
+	public class MockIosNativeBindingService : INativeBindingService
+	{
+		public bool TrySetBinding(object target, string propertyName, BindingBase binding)
+		{
+			var view = target as MockUIView;
+			if (view == null)
+				return false;
+			if (target.GetType().GetProperty(propertyName)?.GetMethod == null)
+				return false;
+			view.SetBinding(propertyName, binding);
+			return true;
+		}
+
+		public bool TrySetBinding(object target, BindableProperty property, BindingBase binding)
+		{
+			var view = target as MockUIView;
+			if (view == null)
+				return false;
+			view.SetBinding(property, binding);
+			return true;
+		}
+
+		public bool TrySetValue(object target, BindableProperty property, object value)
+		{
+			var view = target as MockUIView;
+			if (view == null)
+				return false;
+			view.SetValue(property, value);
+			return true;
+		}
+	}
+
+	public class MockAndroidNativeBindingService : INativeBindingService
+	{
+		public bool TrySetBinding(object target, string propertyName, BindingBase binding)
+		{
+			var view = target as MockAndroidView;
+			if (view == null)
+				return false;
+			view.SetBinding(propertyName, binding);
+			return true;
+		}
+
+		public bool TrySetBinding(object target, BindableProperty property, BindingBase binding)
+		{
+			var view = target as MockAndroidView;
+			if (view == null)
+				return false;
+			view.SetBinding(property, binding);
+			return true;
+		}
+
+		public bool TrySetValue(object target, BindableProperty property, object value)
+		{
+			var view = target as MockAndroidView;
+			if (view == null)
+				return false;
+			view.SetValue(property, value);
+			return true;
+		}
+	}
+
+	public partial class NativeViewsAndBindings : ContentPage
+	{
+		public NativeViewsAndBindings()
+		{
+			InitializeComponent();
+		}
+
+		public NativeViewsAndBindings(bool useCompiledXaml)
+		{
+			//this stub will be replaced at compile time
+		}
+
+		[TestFixture]
+		public class Tests
+		{
+			[SetUp]
+			public void SetUp()
+			{ 
+				Device.PlatformServices = new MockPlatformServices();
+			}
+
+			[TearDown]
+			public void TearDown()
+			{
+				Device.PlatformServices = null;
+			}
+
+			void SetUpPlatform(TargetPlatform platform)
+			{
+				Device.OS = platform;
+				if (platform == TargetPlatform.iOS) {
+					DependencyService.Register<INativeValueConverterService, MockIosNativeValueConverterService>();
+					DependencyService.Register<INativeBindingService, MockIosNativeBindingService>();
+				} else if (platform == TargetPlatform.Android) {
+					DependencyService.Register<INativeValueConverterService, MockAndroidNativeValueConverterService>();
+					DependencyService.Register<INativeBindingService, MockAndroidNativeBindingService>();
+				}
+			}
+
+			[TestCase(false, TargetPlatform.iOS)]
+			[TestCase(false, TargetPlatform.Android)]
+			//[TestCase(true)]
+			public void NativeInContentView(bool useCompiledXaml, TargetPlatform platform)
+			{
+				SetUpPlatform(platform);
+				var layout = new NativeViewsAndBindings(useCompiledXaml);
+				layout.BindingContext = new {
+					Baz = "Bound Value",
+					VerticalOption=LayoutOptions.EndAndExpand
+				};
+				var view = layout.view0;
+				Assert.NotNull(view.Content);
+				MockNativeView nativeView = null;
+				if (platform == TargetPlatform.iOS) {
+					Assert.That(view.Content, Is.TypeOf<MockUIViewWrapper>());
+					Assert.That(((MockUIViewWrapper)view.Content).NativeView, Is.TypeOf<MockUIView>());
+					nativeView = ((MockUIViewWrapper)view.Content).NativeView;
+				} else if (platform == TargetPlatform.Android) {
+					Assert.That(view.Content, Is.TypeOf<MockAndroidViewWrapper>());
+					Assert.That(((MockAndroidViewWrapper)view.Content).NativeView, Is.TypeOf<MockAndroidView>());
+					nativeView = ((MockAndroidViewWrapper)view.Content).NativeView;
+				}
+
+				Assert.AreEqual("foo", nativeView.Foo);
+				Assert.AreEqual(42, nativeView.Bar);
+				Assert.AreEqual("Bound Value", nativeView.Baz);
+				Assert.AreEqual(LayoutOptions.End, view.Content.GetValue(View.HorizontalOptionsProperty));
+				Assert.AreEqual(LayoutOptions.EndAndExpand, view.Content.GetValue(View.VerticalOptionsProperty));
+			}
+		}
+	}
+}
\ No newline at end of file
diff --git a/Xamarin.Forms.Xaml.UnitTests/Xamarin.Forms.Xaml.UnitTests.csproj b/Xamarin.Forms.Xaml.UnitTests/Xamarin.Forms.Xaml.UnitTests.csproj
index 86e2eeb0..26bf6d41 100644
--- a/Xamarin.Forms.Xaml.UnitTests/Xamarin.Forms.Xaml.UnitTests.csproj
+++ b/Xamarin.Forms.Xaml.UnitTests/Xamarin.Forms.Xaml.UnitTests.csproj
@@ -359,6 +359,9 @@
     <Compile Include="TypeExtension.xaml.cs">
       <DependentUpon>TypeExtension.xaml</DependentUpon>
     </Compile>
+    <Compile Include="NativeViewsAndBindings.xaml.cs">
+      <DependentUpon>NativeViewsAndBindings.xaml</DependentUpon>
+    </Compile>
   </ItemGroup>
   <Import Project="$(MSBuildBinPath)\Microsoft.CSharp.targets" />
   <Import Project="..\.nuspec\Xamarin.Forms.Debug.targets" />
@@ -638,6 +641,9 @@
     <EmbeddedResource Include="TypeExtension.xaml">
       <Generator>MSBuild:UpdateDesignTimeXaml</Generator>
     </EmbeddedResource>
+    <EmbeddedResource Include="NativeViewsAndBindings.xaml">
+      <Generator>MSBuild:UpdateDesignTimeXaml</Generator>
+    </EmbeddedResource>
   </ItemGroup>
   <ItemGroup>
     <Service Include="{82A7F48D-3B50-4B1E-B82E-3ADA8210C358}" />