Merge branch '3.0.0'

EmbeddingTestBeds/Embedding.Droid/Embedding.Droid.csproj

@@ -15,7 +15,7 @@
     <AndroidApplication>True</AndroidApplication>
     <AndroidResgenFile>Resources\Resource.Designer.cs</AndroidResgenFile>
     <GenerateSerializationAssemblies>Off</GenerateSerializationAssemblies>
-    <AndroidUseLatestPlatformSdk>True</AndroidUseLatestPlatformSdk>
+    <AndroidUseLatestPlatformSdk>False</AndroidUseLatestPlatformSdk>
     <TargetFrameworkVersion>v8.0</TargetFrameworkVersion>
     <AndroidManifest>Properties\AndroidManifest.xml</AndroidManifest>
     <NuGetPackageImportStamp>

EmbeddingTestBeds/Embedding.XF/Embedding.XF.csproj

@@ -30,5 +30,7 @@
     <ProjectReference Include="..\..\Xamarin.Forms.Platform\Xamarin.Forms.Platform.csproj" />
     <ProjectReference Include="..\..\Xamarin.Forms.Xaml\Xamarin.Forms.Xaml.csproj" />
   </ItemGroup>
-  <Import Project="..\..\.nuspec\Xamarin.Forms.targets" />
-</Project>
+  
+  <Import Project="..\..\.nuspec\Xamarin.Forms.targets" Condition="Exists('..\..\.nuspec\Xamarin.Forms.Build.Tasks.dll')" />
+ 
+</Project> 

PagesGallery/PagesGallery.Droid/PagesGallery.Droid.csproj

@@ -16,7 +16,7 @@
     <AndroidResgenFile>Resources\Resource.Designer.cs</AndroidResgenFile>
     <GenerateSerializationAssemblies>Off</GenerateSerializationAssemblies>
     <AndroidManifest>Properties\AndroidManifest.xml</AndroidManifest>
-    <AndroidUseLatestPlatformSdk>true</AndroidUseLatestPlatformSdk>
+    <AndroidUseLatestPlatformSdk>False</AndroidUseLatestPlatformSdk>
     <TargetFrameworkVersion>v8.0</TargetFrameworkVersion>
     <AndroidSupportedAbis>armeabi,armeabi-v7a,x86</AndroidSupportedAbis>
     <AndroidStoreUncompressedFileExtensions />
@@ -205,7 +205,6 @@
     <AndroidResource Include="Resources\values\styles.xml" />
   </ItemGroup>
   <Import Project="$(MSBuildExtensionsPath)\Xamarin\Android\Xamarin.Android.CSharp.targets" />
-  <Import Project="..\..\.nuspec\Xamarin.Forms.targets" />
   <Target Name="EnsureNuGetPackageBuildImports" BeforeTargets="PrepareForBuild">
     <PropertyGroup>
       <ErrorText>This project references NuGet package(s) that are missing on this computer. Use NuGet Package Restore to download them.  For more information, see http://go.microsoft.com/fwlink/?LinkID=322105. The missing file is {0}.</ErrorText>

PagesGallery/PagesGallery.UWP/PagesGallery.UWP.csproj

@@ -164,7 +164,6 @@
     <VisualStudioVersion>14.0</VisualStudioVersion>
   </PropertyGroup>
   <Import Project="$(MSBuildExtensionsPath)\Microsoft\WindowsXaml\v$(VisualStudioVersion)\Microsoft.Windows.UI.Xaml.CSharp.targets" />
-  <Import Project="..\..\.nuspec\Xamarin.Forms.targets" />
   <!-- To modify your build process, add your task inside one of the targets below and uncomment it. 
        Other similar extension points exist, see Microsoft.Common.targets.
   <Target Name="BeforeBuild">

PagesGallery/PagesGallery.iOS/PagesGallery.iOS.csproj

@@ -157,7 +157,6 @@
     <Reference Include="Xamarin.iOS" />
   </ItemGroup>
   <Import Project="$(MSBuildExtensionsPath)\Xamarin\iOS\Xamarin.iOS.CSharp.targets" />
-  <Import Project="..\..\.nuspec\Xamarin.Forms.targets" />
   <Import Project="..\..\packages\NETStandard.Library.2.0.0\build\netstandard2.0\NETStandard.Library.targets" Condition="Exists('..\..\packages\NETStandard.Library.2.0.0\build\netstandard2.0\NETStandard.Library.targets')" />
   <Target Name="EnsureNuGetPackageBuildImports" BeforeTargets="PrepareForBuild">
     <PropertyGroup>

PagesGallery/PagesGallery/PagesGallery.csproj

@@ -28,5 +28,5 @@
     <ProjectReference Include="..\..\Xamarin.Forms.Xaml\Xamarin.Forms.Xaml.csproj" />
   </ItemGroup>
 
-  <Import Project="..\..\.nuspec\Xamarin.Forms.targets" />
+  <Import Project="..\..\.nuspec\Xamarin.Forms.targets" Condition="Exists('..\..\.nuspec\Xamarin.Forms.Build.Tasks.dll')" />
 </Project>

Stubs/Xamarin.Forms.Platform.Android/Xamarin.Forms.Platform.Android (Forwarders).csproj

@@ -14,7 +14,7 @@
     <FileAlignment>512</FileAlignment>
     <AndroidResgenFile>Resources\Resource.Designer.cs</AndroidResgenFile>
     <GenerateSerializationAssemblies>Off</GenerateSerializationAssemblies>
-    <AndroidUseLatestPlatformSdk>True</AndroidUseLatestPlatformSdk>
+    <AndroidUseLatestPlatformSdk>False</AndroidUseLatestPlatformSdk>
     <DevInstrumentationEnabled>True</DevInstrumentationEnabled>
     <SolutionDir Condition="$(SolutionDir) == '' Or $(SolutionDir) == '*Undefined*'">..\..\</SolutionDir>
     <RestorePackages>true</RestorePackages>

Xamarin.Forms.Build.Tasks/CompiledConverters/BindablePropertyConverter.cs

@@ -1,5 +1,6 @@
 using System.Collections.Generic;
 using System.Linq;
+using System.Xml;
 using Mono.Cecil;
 using Mono.Cecil.Cil;
 
@@ -32,27 +33,23 @@ namespace Xamarin.Forms.Core.XamlC
 			var parts = value.Split('.');
 			if (parts.Length == 1) {
 				var parent = node.Parent?.Parent as IElementNode ?? (node.Parent?.Parent as IListNode)?.Parent as IElementNode;
-
-				if ((node.Parent as ElementNode)?.XmlType.NamespaceUri == XamlParser.XFUri &&
-				    ((node.Parent as ElementNode)?.XmlType.Name == "Setter" || (node.Parent as ElementNode)?.XmlType.Name == "PropertyCondition")) {
+				if (   (node.Parent as ElementNode)?.XmlType.NamespaceUri == XamlParser.XFUri
+				    && (   (node.Parent as ElementNode)?.XmlType.Name == nameof(Setter)
+				        || (node.Parent as ElementNode)?.XmlType.Name == nameof(PropertyCondition))) {
 					if (parent.XmlType.NamespaceUri == XamlParser.XFUri &&
-						(parent.XmlType.Name == "Trigger" || parent.XmlType.Name == "DataTrigger" || parent.XmlType.Name == "MultiTrigger" || parent.XmlType.Name == "Style")) {
+					    (   parent.XmlType.Name == nameof(Trigger)
+					     || parent.XmlType.Name == nameof(DataTrigger)
+					     || parent.XmlType.Name == nameof(MultiTrigger)
+					     || parent.XmlType.Name == nameof(Style))) {
 						var ttnode = (parent as ElementNode).Properties [new XmlName("", "TargetType")];
 						if (ttnode is ValueNode)
 							typeName = (ttnode as ValueNode).Value as string;
 						else if (ttnode is IElementNode)
 							typeName = ((ttnode as IElementNode).CollectionItems.FirstOrDefault() as ValueNode)?.Value as string ?? ((ttnode as IElementNode).Properties [new XmlName("", "TypeName")] as ValueNode)?.Value as string;
-					} else if (parent.XmlType.NamespaceUri == XamlParser.XFUri && parent.XmlType.Name == "VisualState") {
-						var current = parent.Parent.Parent.Parent as IElementNode;
-						if (current.XmlType.NamespaceUri == XamlParser.XFUri && current.XmlType.Name == "Setter") {
-							// Parent will be a Style, and the type will be that Style's TargetType
-							typeName =
-								((current?.Parent as IElementNode)?.Properties[new XmlName("", "TargetType")] as ValueNode)?.Value as string;
-						} else {
-							typeName = current.XmlType.Name;
-						}
+					} else if (parent.XmlType.NamespaceUri == XamlParser.XFUri && parent.XmlType.Name == nameof(VisualState)) {
+						typeName = FindTypeNameForVisualState(parent, node);
 					}
-				} else if ((node.Parent as ElementNode)?.XmlType.NamespaceUri == XamlParser.XFUri && (node.Parent as ElementNode)?.XmlType.Name == "Trigger")
+				} else if ((node.Parent as ElementNode)?.XmlType.NamespaceUri == XamlParser.XFUri && (node.Parent as ElementNode)?.XmlType.Name == nameof(Trigger))
 					typeName = ((node.Parent as ElementNode).Properties [new XmlName("", "TargetType")] as ValueNode).Value as string;
 				propertyName = parts [0];
 			} else if (parts.Length == 2) {
@@ -73,6 +70,29 @@ namespace Xamarin.Forms.Core.XamlC
 			return bpRef;
 		}
 
+		static string FindTypeNameForVisualState(IElementNode parent, IXmlLineInfo lineInfo)
+		{
+			//1. parent is VisualState, don't check that
+
+			//2. check that the VS is in a VSG
+			if (!(parent.Parent is IElementNode target) || target.XmlType.NamespaceUri != XamlParser.XFUri || target.XmlType.Name != nameof(VisualStateGroup))
+				throw new XamlParseException($"Expected {nameof(VisualStateGroup)} but found {parent.Parent}", lineInfo);
+
+			//3. if the VSG is in a VSGL, skip that as it could be implicit
+			if (   target.Parent is ListNode
+				|| (  (target.Parent as IElementNode)?.XmlType.NamespaceUri == XamlParser.XFUri
+				   && (target.Parent as IElementNode)?.XmlType.Name == nameof(VisualStateGroupList)))
+				target = target.Parent.Parent as IElementNode;
+			else
+				target = target.Parent as IElementNode;
+
+			//4. target is now a Setter in a Style, or a VE
+			if (target.XmlType.NamespaceUri == XamlParser.XFUri && target.XmlType.Name == nameof(Setter))
+				return ((target?.Parent as IElementNode)?.Properties[new XmlName("", "TargetType")] as ValueNode)?.Value as string;
+			else
+				return target.XmlType.Name;
+		}
+
 		public static FieldReference GetBindablePropertyFieldReference(TypeReference typeRef, string propertyName, ModuleDefinition module)
 		{
 			TypeReference declaringTypeReference;

Xamarin.Forms.ControlGallery.Android/Xamarin.Forms.ControlGallery.Android.csproj

@@ -22,7 +22,7 @@
     <AndroidStoreUncompressedFileExtensions />
     <MandroidI18n />
     <JavaOptions />
-    <AndroidUseLatestPlatformSdk>True</AndroidUseLatestPlatformSdk>
+    <AndroidUseLatestPlatformSdk>False</AndroidUseLatestPlatformSdk>
     <SolutionDir Condition="$(SolutionDir) == '' Or $(SolutionDir) == '*Undefined*'">..\</SolutionDir>
     <RestorePackages>true</RestorePackages>
     <NuGetPackageImportStamp>

Xamarin.Forms.Controls/Xamarin.Forms.Controls.csproj

@@ -30,7 +30,8 @@
     <ProjectReference Include="..\Xamarin.Forms.Maps\Xamarin.Forms.Maps.csproj" />
     <ProjectReference Include="..\Xamarin.Forms.Xaml\Xamarin.Forms.Xaml.csproj" />
   </ItemGroup>
-  <Import Project="..\.nuspec\Xamarin.Forms.targets" />
+  
+  <Import Project="..\.nuspec\Xamarin.Forms.targets" Condition="Exists('..\.nuspec\Xamarin.Forms.Build.Tasks.dll')" />
 
   <ItemGroup>
     <EmbeddedResource Include="BuildNumber.txt" />

Xamarin.Forms.Core.UnitTests/BindableObjectUnitTests.cs

@@ -922,7 +922,7 @@ namespace Xamarin.Forms.Core.UnitTests
 		}
 
 		[Test]
-		public void IsSetIsFalseWhenPropSetByDefaultValueCreator()
+		public void IsSetIsTrueWhenPropSetByDefaultValueCreator()
 		{
 			string defaultValue = "default";
 			string defaultValueC = "defaultVC";
@@ -939,7 +939,7 @@ namespace Xamarin.Forms.Core.UnitTests
 			Assert.AreEqual(defaultValueC, created);
 
 			var isSet = bindable.IsSet(bindableProperty);
-			Assert.IsFalse(isSet);
+			Assert.IsTrue(isSet);
 		}
 
 		[Test]
@@ -1509,6 +1509,19 @@ namespace Xamarin.Forms.Core.UnitTests
 			Assert.IsTrue(locator.Count == 1);
 		}
 
+		[Test]
+		//https://github.com/xamarin/Xamarin.Forms/issues/2019
+		public void EventSubscribingOnBindingContextChanged()
+		{
+			var source = new MockBindable();
+			var bindable = new MockBindable();
+			var property = BindableProperty.Create("foo", typeof(string), typeof(MockBindable), null);
+			bindable.SetBinding(property, new Binding("BindingContext", source: source));
+			Assert.That((string)bindable.GetValue(property), Is.EqualTo(null));
+			BindableObject.SetInheritedBindingContext(source, "bar"); //inherited BC, only trigger BCChanged
+			Assert.That((string)bindable.GetValue(property), Is.EqualTo("bar"));
+		}
+
 		[Test]
 		public void BindingsEditableAfterUnapplied()
 		{

Xamarin.Forms.Core/BindableObject.cs

@@ -287,12 +287,10 @@ namespace Xamarin.Forms
 			if (binding == null)
 				throw new ArgumentNullException("binding");
 
-			BindablePropertyContext context = null;
-			if (fromStyle && (context = GetContext(targetProperty)) != null && (context.Attributes & BindableContextAttributes.IsDefaultValue) == 0 &&
-				(context.Attributes & BindableContextAttributes.IsSetFromStyle) == 0)
+			if (fromStyle && !CanBeSetFromStyle(targetProperty))
 				return;
 
-			context = context ?? GetOrCreateContext(targetProperty);
+			var context = GetOrCreateContext(targetProperty);
 			if (fromStyle)
 				context.Attributes |= BindableContextAttributes.IsSetFromStyle;
 			else
@@ -309,6 +307,20 @@ namespace Xamarin.Forms
 			binding.Apply(BindingContext, this, targetProperty);
 		}
 
+		bool CanBeSetFromStyle(BindableProperty property)
+		{
+			var context = GetContext(property);
+			if (context == null)
+				return true;
+			if ((context.Attributes & BindableContextAttributes.IsSetFromStyle) == BindableContextAttributes.IsSetFromStyle)
+				return true;
+			if ((context.Attributes & BindableContextAttributes.IsDefaultValue) == BindableContextAttributes.IsDefaultValue)
+				return true;
+			if ((context.Attributes & BindableContextAttributes.IsDefaultValueCreated) == BindableContextAttributes.IsDefaultValueCreated)
+				return true;
+			return false;
+		}
+
 		internal void SetDynamicResource(BindableProperty property, string key)
 		{
 			SetDynamicResource(property, key, false);
@@ -320,13 +332,10 @@ namespace Xamarin.Forms
 				throw new ArgumentNullException(nameof(property));
 			if (string.IsNullOrEmpty(key))
 				throw new ArgumentNullException(nameof(key));
-
-			BindablePropertyContext context = null;
-			if (fromStyle && (context = GetContext(property)) != null && (context.Attributes & BindableContextAttributes.IsDefaultValue) == 0 &&
-				(context.Attributes & BindableContextAttributes.IsSetFromStyle) == 0)
+			if (fromStyle && !CanBeSetFromStyle(property))
 				return;
 
-			context = context ?? GetOrCreateContext(property);
+			var context = GetOrCreateContext(property);
 
 			context.Attributes |= BindableContextAttributes.IsDynamicResource;
 			if (fromStyle)
@@ -471,9 +480,7 @@ namespace Xamarin.Forms
 			if (bpcontext == null)
 				return;
 
-			if (   fromStyle && bpcontext != null
-				&& (bpcontext.Attributes & BindableContextAttributes.IsDefaultValue) != 0
-				&& (bpcontext.Attributes & BindableContextAttributes.IsSetFromStyle) == 0)
+			if (fromStyle && !CanBeSetFromStyle(property))
 				return;
 
 			object original = bpcontext.Value;
@@ -490,7 +497,10 @@ namespace Xamarin.Forms
 
 			bpcontext.Attributes &= ~BindableContextAttributes.IsManuallySet;
 			bpcontext.Value = newValue;
-			bpcontext.Attributes |= BindableContextAttributes.IsDefaultValue;
+			if (property.DefaultValueCreator == null)
+				bpcontext.Attributes |= BindableContextAttributes.IsDefaultValue;
+			else
+				bpcontext.Attributes |= BindableContextAttributes.IsDefaultValueCreated;
 
 			if (!same)
 			{
@@ -504,8 +514,10 @@ namespace Xamarin.Forms
 		{
 			var context = new BindablePropertyContext { Property = property, Value = property.DefaultValueCreator != null ? property.DefaultValueCreator(this) : property.DefaultValue };
 
-			if (property.DefaultValueCreator != null)
+			if (property.DefaultValueCreator == null)
 				context.Attributes = BindableContextAttributes.IsDefaultValue;
+			else
+				context.Attributes = BindableContextAttributes.IsDefaultValueCreated;
 
 			_properties.Add(context);
 			return context;
@@ -555,9 +567,7 @@ namespace Xamarin.Forms
 			if (checkAccess && property.IsReadOnly)
 				throw new InvalidOperationException(string.Format("The BindableProperty \"{0}\" is readonly.", property.PropertyName));
 
-			BindablePropertyContext context = null;
-			if (fromStyle && (context = GetContext(property)) != null && (context.Attributes & BindableContextAttributes.IsDefaultValue) == 0 &&
-				(context.Attributes & BindableContextAttributes.IsSetFromStyle) == 0)
+			if (fromStyle && !CanBeSetFromStyle(property))
 				return;
 
 			SetValueCore(property, value, SetValueFlags.ClearOneWayBindings | SetValueFlags.ClearDynamicResource,
@@ -586,6 +596,7 @@ namespace Xamarin.Forms
 			}
 
 			context.Attributes &= ~BindableContextAttributes.IsDefaultValue;
+			context.Attributes &= ~BindableContextAttributes.IsDefaultValueCreated;
 
 			if ((context.Attributes & BindableContextAttributes.IsDynamicResource) != 0 && clearDynamicResources)
 				RemoveDynamicResource(property);
@@ -622,7 +633,8 @@ namespace Xamarin.Forms
 			IsBeingSet = 1 << 1,
 			IsDynamicResource = 1 << 2,
 			IsSetFromStyle = 1 << 3,
-			IsDefaultValue = 1 << 4
+			IsDefaultValue = 1 << 4,
+			IsDefaultValueCreated = 1 << 5,
 		}
 
 		class BindablePropertyContext

Xamarin.Forms.Core/BindingExpression.cs

@@ -146,9 +146,7 @@ namespace Xamarin.Forms
 				{
 					var inpc = current as INotifyPropertyChanged;
 					if (inpc != null && !ReferenceEquals(current, previous))
-					{
 						part.Subscribe(inpc);
-					}
 				}
 
 				previous = current;
@@ -460,11 +458,13 @@ namespace Xamarin.Forms
 			readonly WeakReference<INotifyPropertyChanged> _source = new WeakReference<INotifyPropertyChanged>(null);
 			readonly WeakReference<PropertyChangedEventHandler> _listener = new WeakReference<PropertyChangedEventHandler>(null);
 			readonly PropertyChangedEventHandler _handler;
+			readonly EventHandler _bchandler;
 			internal WeakReference<INotifyPropertyChanged> Source => _source;
 
 			public WeakPropertyChangedProxy()
 			{
 				_handler = new PropertyChangedEventHandler(OnPropertyChanged);
+				_bchandler = new EventHandler(OnBCChanged);
 			}
 
 			public WeakPropertyChangedProxy(INotifyPropertyChanged source, PropertyChangedEventHandler listener) : this()
@@ -475,6 +475,9 @@ namespace Xamarin.Forms
 			public void SubscribeTo(INotifyPropertyChanged source, PropertyChangedEventHandler listener)
 			{
 				source.PropertyChanged += _handler;
+				var bo = source as BindableObject;
+				if (bo != null)
+					bo.BindingContextChanged += _bchandler;
 				_source.SetTarget(source);
 				_listener.SetTarget(listener);
 			}
@@ -484,6 +487,10 @@ namespace Xamarin.Forms
 				INotifyPropertyChanged source;
 				if (_source.TryGetTarget(out source) && source != null)
 					source.PropertyChanged -= _handler;
+				var bo = source as BindableObject;
+				if (bo != null)
+					bo.BindingContextChanged -= _bchandler;
+
 				_source.SetTarget(null);
 				_listener.SetTarget(null);
 			}
@@ -496,6 +503,11 @@ namespace Xamarin.Forms
 				else
 					Unsubscribe();
 			}
+
+			void OnBCChanged(object sender, EventArgs e)
+			{
+				OnPropertyChanged(sender, new PropertyChangedEventArgs("BindingContext"));
+			}
 		}
 
 		class BindingExpressionPart
@@ -518,10 +530,8 @@ namespace Xamarin.Forms
 			{
 				INotifyPropertyChanged source;
 				if (_listener != null && _listener.Source.TryGetTarget(out source) && ReferenceEquals(handler, source))
-				{
 					// Already subscribed
 					return;
-				}
 
 				// Clear out the old subscription if necessary
 				Unsubscribe();
@@ -616,4 +626,4 @@ namespace Xamarin.Forms
 			}
 		}
 	}
-}
+}

Xamarin.Forms.Maps.Android/Xamarin.Forms.Maps.Android.csproj

@@ -15,7 +15,7 @@
     <FileAlignment>512</FileAlignment>
     <AndroidResgenFile>Resources\Resource.Designer.cs</AndroidResgenFile>
     <GenerateSerializationAssemblies>Off</GenerateSerializationAssemblies>
-    <AndroidUseLatestPlatformSdk>true</AndroidUseLatestPlatformSdk>
+    <AndroidUseLatestPlatformSdk>False</AndroidUseLatestPlatformSdk>
     <TargetFrameworkVersion>v8.0</TargetFrameworkVersion>
     <SolutionDir Condition="$(SolutionDir) == '' Or $(SolutionDir) == '*Undefined*'">..\</SolutionDir>
     <RestorePackages>true</RestorePackages>

Xamarin.Forms.Platform.Android.AppLinks/Xamarin.Forms.Platform.Android.AppLinks.csproj

@@ -12,7 +12,7 @@
     <MonoAndroidResourcePrefix>Resources</MonoAndroidResourcePrefix>
     <AndroidResgenClass>Resource</AndroidResgenClass>
     <AndroidResgenFile>Resources\Resource.designer.cs</AndroidResgenFile>
-    <AndroidUseLatestPlatformSdk>True</AndroidUseLatestPlatformSdk>
+    <AndroidUseLatestPlatformSdk>False</AndroidUseLatestPlatformSdk>
     <AssemblyName>Xamarin.Forms.Platform.Android.AppLinks</AssemblyName>
     <TargetFrameworkVersion>v8.0</TargetFrameworkVersion>
     <NuGetPackageImportStamp>

Xamarin.Forms.Platform.Android.FormsViewGroup/Xamarin.Forms.Platform.Android.FormsViewGroup.csproj

@@ -15,7 +15,7 @@
     <RootNamespace>FormsViewGroup</RootNamespace>
     <AssemblyName>FormsViewGroup</AssemblyName>
     <FileAlignment>512</FileAlignment>
-    <AndroidUseLatestPlatformSdk>True</AndroidUseLatestPlatformSdk>
+    <AndroidUseLatestPlatformSdk>False</AndroidUseLatestPlatformSdk>
     <TargetFrameworkVersion>v7.0</TargetFrameworkVersion>
   </PropertyGroup>
   <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">

Xamarin.Forms.Platform.Android/Xamarin.Forms.Platform.Android.csproj

@@ -15,7 +15,7 @@
     <AndroidResgenFile>Resources\Resource.Designer.cs</AndroidResgenFile>
     <GenerateSerializationAssemblies>Off</GenerateSerializationAssemblies>
     <TargetFrameworkVersion>v8.0</TargetFrameworkVersion>
-    <AndroidUseLatestPlatformSdk>true</AndroidUseLatestPlatformSdk>
+    <AndroidUseLatestPlatformSdk>False</AndroidUseLatestPlatformSdk>
     <SolutionDir Condition="$(SolutionDir) == '' Or $(SolutionDir) == '*Undefined*'">..\</SolutionDir>
     <RestorePackages>true</RestorePackages>
     <NuGetPackageImportStamp>

Xamarin.Forms.Xaml.UnitTests/Issues/Gh2034.xaml

@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
+             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
+             x:Class="Xamarin.Forms.Xaml.UnitTests.Gh2034">
+    <FlexLayout StyleClass="login-form">
+        <Label >
+            <VisualStateManager.VisualStateGroups>
+                    <VisualStateGroupList>
+                        <VisualStateGroup x:Name="StrengthStates">
+                                
+                            <VisualState x:Name="VeryWeak">
+                                <VisualState.Setters>
+                                    <Setter Property="Text" Value="foo"/>
+                                </VisualState.Setters>
+                            </VisualState>
+                        </VisualStateGroup>
+                </VisualStateGroupList>
+            </VisualStateManager.VisualStateGroups>
+        </Label>
+    </FlexLayout>
+</ContentPage>

Xamarin.Forms.Xaml.UnitTests/Issues/Gh2034.xaml.cs

@@ -0,0 +1,33 @@
+using System;
+using System.Collections.Generic;
+using NUnit.Framework;
+using Xamarin.Forms;
+
+namespace Xamarin.Forms.Xaml.UnitTests
+{
+	[XamlCompilation(XamlCompilationOptions.Skip)]
+	public partial class Gh2034 : ContentPage
+	{
+		public Gh2034()
+		{
+			InitializeComponent();
+		}
+		public Gh2034(bool useCompiledXaml)
+		{
+			//this stub will be replaced at compile time
+		}
+
+		[TestFixture]
+		class Tests
+		{
+			[TestCase(true)]
+			public void Compiles(bool useCompiledXaml)
+			{
+				if (!useCompiledXaml)
+					return;
+				MockCompiler.Compile(typeof(Gh2034));
+				Assert.Pass();
+			}
+		}
+	}
+}

Xamarin.Forms.Xaml.UnitTests/Xamarin.Forms.Xaml.UnitTests.csproj

@@ -579,9 +579,14 @@
     <Compile Include="Issues\Gh1978.xaml.cs">
       <DependentUpon>Gh1978.xaml</DependentUpon>
     </Compile>
+    <Compile Include="Issues\Gh2034.xaml.cs">
+      <DependentUpon>Gh2034.xaml</DependentUpon>
+    </Compile>
   </ItemGroup>
   <Import Project="$(MSBuildBinPath)\Microsoft.CSharp.targets" />
-  <Import Project="..\.nuspec\Xamarin.Forms.Debug.targets" />
+  
+  <Import Project="..\.nuspec\Xamarin.Forms.Debug.targets" Condition="Exists('..\.nuspec\Xamarin.Forms.Build.Tasks.dll')" />
+  
   <ItemGroup>
     <ProjectReference Include="..\Xamarin.Forms.Core\Xamarin.Forms.Core.csproj">
       <Project>{57B8B73D-C3B5-4C42-869E-7B2F17D354AC}</Project>
@@ -1036,6 +1041,10 @@
       <SubType>Designer</SubType>
       <Generator>MSBuild:UpdateDesignTimeXaml</Generator>
     </EmbeddedResource>
+    <EmbeddedResource Include="Issues\Gh2034.xaml">
+      <SubType>Designer</SubType>
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