diff --git a/Xamarin.Forms.Build.Tasks/SetPropertiesVisitor.cs b/Xamarin.Forms.Build.Tasks/SetPropertiesVisitor.cs index 64bc75859..8b2a25fb3 100644 --- a/Xamarin.Forms.Build.Tasks/SetPropertiesVisitor.cs +++ b/Xamarin.Forms.Build.Tasks/SetPropertiesVisitor.cs @@ -279,6 +279,7 @@ namespace Xamarin.Forms.Build.Tasks else if (vardefref.VariableDefinition.VariableType.ImplementsGenericInterface("Xamarin.Forms.Xaml.IMarkupExtension`1", out markupExtension, out genericArguments)) { + var acceptEmptyServiceProvider = vardefref.VariableDefinition.VariableType.GetCustomAttribute(module.ImportReference(typeof(AcceptEmptyServiceProviderAttribute))) != null; if (vardefref.VariableDefinition.VariableType.FullName == "Xamarin.Forms.Xaml.BindingExtension") foreach (var instruction in CompileBindingPath(node, context, vardefref.VariableDefinition)) yield return instruction; @@ -291,26 +292,34 @@ namespace Xamarin.Forms.Build.Tasks vardefref.VariableDefinition = new VariableDefinition(module.ImportReference(genericArguments.First())); yield return Instruction.Create(OpCodes.Ldloc, context.Variables[node]); - foreach (var instruction in node.PushServiceProvider(context, bpRef, propertyRef, propertyDeclaringTypeRef)) - yield return instruction; + if (acceptEmptyServiceProvider) + yield return Instruction.Create(OpCodes.Ldnull); + else + foreach (var instruction in node.PushServiceProvider(context, bpRef, propertyRef, propertyDeclaringTypeRef)) + yield return instruction; yield return Instruction.Create(OpCodes.Callvirt, provideValue); yield return Instruction.Create(OpCodes.Stloc, vardefref.VariableDefinition); } else if (context.Variables[node].VariableType.ImplementsInterface(module.ImportReference(typeof (IMarkupExtension)))) { + var acceptEmptyServiceProvider = context.Variables[node].VariableType.GetCustomAttribute(module.ImportReference(typeof(AcceptEmptyServiceProviderAttribute))) != null; var markExt = module.ImportReference(typeof (IMarkupExtension)).Resolve(); var provideValueInfo = markExt.Methods.First(md => md.Name == "ProvideValue"); var provideValue = module.ImportReference(provideValueInfo); vardefref.VariableDefinition = new VariableDefinition(module.TypeSystem.Object); yield return Instruction.Create(OpCodes.Ldloc, context.Variables[node]); - foreach (var instruction in node.PushServiceProvider(context, bpRef, propertyRef, propertyDeclaringTypeRef)) - yield return instruction; + if (acceptEmptyServiceProvider) + yield return Instruction.Create(OpCodes.Ldnull); + else + foreach (var instruction in node.PushServiceProvider(context, bpRef, propertyRef, propertyDeclaringTypeRef)) + yield return instruction; yield return Instruction.Create(OpCodes.Callvirt, provideValue); yield return Instruction.Create(OpCodes.Stloc, vardefref.VariableDefinition); } else if (context.Variables[node].VariableType.ImplementsInterface(module.ImportReference(typeof (IValueProvider)))) { + var acceptEmptyServiceProvider = context.Variables[node].VariableType.GetCustomAttribute(module.ImportReference(typeof(AcceptEmptyServiceProviderAttribute))) != null; var valueProviderType = context.Variables[node].VariableType; //If the IValueProvider has a ProvideCompiledAttribute that can be resolved, shortcut this var compiledValueProviderName = valueProviderType?.GetCustomAttribute(module.ImportReference(typeof(ProvideCompiledAttribute)))?.ConstructorArguments?[0].Value as string; @@ -334,8 +343,11 @@ namespace Xamarin.Forms.Build.Tasks vardefref.VariableDefinition = new VariableDefinition(module.TypeSystem.Object); yield return Instruction.Create(OpCodes.Ldloc, context.Variables[node]); - foreach (var instruction in node.PushServiceProvider(context, bpRef, propertyRef, propertyDeclaringTypeRef)) - yield return instruction; + if (acceptEmptyServiceProvider) + yield return Instruction.Create(OpCodes.Ldnull); + else + foreach (var instruction in node.PushServiceProvider(context, bpRef, propertyRef, propertyDeclaringTypeRef)) + yield return instruction; yield return Instruction.Create(OpCodes.Callvirt, provideValue); yield return Instruction.Create(OpCodes.Stloc, vardefref.VariableDefinition); } diff --git a/Xamarin.Forms.Core/IMarkupExtension.cs b/Xamarin.Forms.Core/IMarkupExtension.cs index 24a435f9d..2b32f3894 100644 --- a/Xamarin.Forms.Core/IMarkupExtension.cs +++ b/Xamarin.Forms.Core/IMarkupExtension.cs @@ -11,4 +11,9 @@ namespace Xamarin.Forms.Xaml { object ProvideValue(IServiceProvider serviceProvider); } + + [AttributeUsage(AttributeTargets.Class, Inherited = false)] + public sealed class AcceptEmptyServiceProviderAttribute : Attribute + { + } } \ No newline at end of file diff --git a/Xamarin.Forms.Xaml.UnitTests/AcceptEmptyServiceProvider.xaml b/Xamarin.Forms.Xaml.UnitTests/AcceptEmptyServiceProvider.xaml new file mode 100644 index 000000000..b39bd2878 --- /dev/null +++ b/Xamarin.Forms.Xaml.UnitTests/AcceptEmptyServiceProvider.xaml @@ -0,0 +1,6 @@ + + + \ No newline at end of file diff --git a/Xamarin.Forms.Xaml.UnitTests/AcceptEmptyServiceProvider.xaml.cs b/Xamarin.Forms.Xaml.UnitTests/AcceptEmptyServiceProvider.xaml.cs new file mode 100644 index 000000000..611cb36e8 --- /dev/null +++ b/Xamarin.Forms.Xaml.UnitTests/AcceptEmptyServiceProvider.xaml.cs @@ -0,0 +1,61 @@ +using System; +using System.Collections.Generic; +using NUnit.Framework; +using Xamarin.Forms; +using Xamarin.Forms.Core.UnitTests; + +namespace Xamarin.Forms.Xaml.UnitTests +{ + [AcceptEmptyServiceProvider] + public class FooExtension : IMarkupExtension + { + public IServiceProvider ProvideValue(IServiceProvider serviceProvider) + { + return serviceProvider; + } + + object IMarkupExtension.ProvideValue(IServiceProvider serviceProvider) + { + return (this as IMarkupExtension).ProvideValue(serviceProvider); + } + } + + public partial class AcceptEmptyServiceProvider : ContentPage + { + public AcceptEmptyServiceProvider() + { + InitializeComponent(); + } + + public AcceptEmptyServiceProvider(bool useCompiledXaml) + { + //this stub will be replaced at compile time + } + + public IServiceProvider ServiceProvider { get; set; } + + [TestFixture] + class Tests + { + [SetUp] + public void Setup() + { + Device.PlatformServices = new MockPlatformServices(); + } + + [TearDown] + public void TearDown() + { + Device.PlatformServices = null; + } + + [TestCase(true)] + [TestCase(false)] + public void ServiceProviderIsNullOnAttributedExtensions(bool useCompiledXaml) + { + var p = new AcceptEmptyServiceProvider(useCompiledXaml); + Assert.IsNull(p.ServiceProvider); + } + } + } +} diff --git a/Xamarin.Forms.Xaml.UnitTests/Xamarin.Forms.Xaml.UnitTests.csproj b/Xamarin.Forms.Xaml.UnitTests/Xamarin.Forms.Xaml.UnitTests.csproj index 4b3e5c86c..90bab284d 100644 --- a/Xamarin.Forms.Xaml.UnitTests/Xamarin.Forms.Xaml.UnitTests.csproj +++ b/Xamarin.Forms.Xaml.UnitTests/Xamarin.Forms.Xaml.UnitTests.csproj @@ -441,6 +441,10 @@ Bz44216.xaml + AcceptEmptyServiceProvider.xaml + + + AcceptEmptyServiceProvider.xaml @@ -805,6 +809,9 @@ MSBuild:UpdateDesignTimeXaml + + MSBuild:UpdateDesignTimeXaml + diff --git a/Xamarin.Forms.Xaml/ApplyPropertiesVisitor.cs b/Xamarin.Forms.Xaml/ApplyPropertiesVisitor.cs index 833d5d949..5b8a84030 100644 --- a/Xamarin.Forms.Xaml/ApplyPropertiesVisitor.cs +++ b/Xamarin.Forms.Xaml/ApplyPropertiesVisitor.cs @@ -91,12 +91,12 @@ namespace Xamarin.Forms.Xaml var valueProvider = value as IValueProvider; if (markupExtension != null) { - var serviceProvider = new XamlServiceProvider(node, Context); + var serviceProvider = value.GetType().GetTypeInfo().GetCustomAttribute() == null ? new XamlServiceProvider(node, Context) : null; value = markupExtension.ProvideValue(serviceProvider); } if (valueProvider != null) { - var serviceProvider = new XamlServiceProvider(node, Context); + var serviceProvider = value.GetType().GetTypeInfo().GetCustomAttribute() == null ? new XamlServiceProvider(node, Context) : null; value = valueProvider.ProvideValue(serviceProvider); } diff --git a/docs/Xamarin.Forms.Core/Xamarin.Forms.Xaml/AcceptEmptyServiceProviderAttribute.xml b/docs/Xamarin.Forms.Core/Xamarin.Forms.Xaml/AcceptEmptyServiceProviderAttribute.xml new file mode 100644 index 000000000..d95dffa3e --- /dev/null +++ b/docs/Xamarin.Forms.Core/Xamarin.Forms.Xaml/AcceptEmptyServiceProviderAttribute.xml @@ -0,0 +1,36 @@ + + + + + Xamarin.Forms.Core + 2.0.0.0 + + + System.Attribute + + + + + System.AttributeUsage(System.AttributeTargets.Class, Inherited=false) + + + + To be added. + To be added. + + + + + + Constructor + + 2.0.0.0 + + + + To be added. + To be added. + + + + diff --git a/docs/Xamarin.Forms.Core/index.xml b/docs/Xamarin.Forms.Core/index.xml index 89af75c21..1b1cf3100 100644 --- a/docs/Xamarin.Forms.Core/index.xml +++ b/docs/Xamarin.Forms.Core/index.xml @@ -494,6 +494,7 @@ +