Started implementing XAML lifecycle listener.

We need to delay bindings until everything is set up before everything
works though.

src/Markup/Perspex.Markup.Xaml/Context/PerspexLifeCycleListener.cs

@@ -0,0 +1,31 @@
+// Copyright (c) The Perspex Project. All rights reserved.
+// Licensed under the MIT license. See licence.md file in the project root for full license information.
+
+using System;
+using OmniXaml;
+
+namespace Perspex.Markup.Xaml.Context
+{
+    public class PerspexLifeCycleListener : IInstanceLifeCycleListener
+    {
+        public void OnAfterProperties(object instance)
+        {
+        }
+
+        public void OnAssociatedToParent(object instance)
+        {
+        }
+
+        public void OnBegin(object instance)
+        {
+            var isi = instance as ISupportInitialize;
+            isi?.BeginInit();
+        }
+
+        public void OnEnd(object instance)
+        {
+            var isi = instance as ISupportInitialize;
+            isi?.EndInit();
+        }
+    }
+}

src/Markup/Perspex.Markup.Xaml/Perspex.Markup.Xaml.csproj

@@ -42,6 +42,7 @@
     </Compile>
     <Compile Include="Context\NameScopeWrapper.cs" />
     <Compile Include="Context\PerspexAttachableXamlMember.cs" />
+    <Compile Include="Context\PerspexLifeCycleListener.cs" />
     <Compile Include="Context\PerspexMemberValuePlugin.cs" />
     <Compile Include="Context\PerspexNamespaceRegistry.cs" />
     <Compile Include="Context\PerspexObjectAssembler.cs" />

src/Markup/Perspex.Markup.Xaml/PerspexXamlLoader.cs

@@ -20,6 +20,7 @@ namespace Perspex.Markup.Xaml
     public class PerspexXamlLoader : XmlLoader
     {
         private static PerspexParserFactory s_parserFactory;
+        private static IInstanceLifeCycleListener s_lifeCycleListener = new PerspexLifeCycleListener();
 
         /// <summary>
         /// Initializes a new instance of the <see cref="PerspexXamlLoader"/> class.
@@ -77,7 +78,7 @@ namespace Perspex.Markup.Xaml
                 {
                     using (var stream = assetLocator.Open(uri))
                     {
-                        return Load(stream, new Settings { RootInstance = rootInstance });
+                        return Load(stream, rootInstance);
                     }
                 }
             }
@@ -106,7 +107,7 @@ namespace Perspex.Markup.Xaml
 
             using (var stream = assetLocator.Open(uri))
             {
-                return Load(stream, new Settings { RootInstance = rootInstance });
+                return Load(stream, rootInstance);
             }
         }
 
@@ -124,7 +125,7 @@ namespace Perspex.Markup.Xaml
 
             using (var stream = new MemoryStream(Encoding.UTF8.GetBytes(xaml)))
             {
-                return Load(stream, new Settings { RootInstance = rootInstance });
+                return Load(stream, rootInstance);
             }
         }
 
@@ -151,5 +152,14 @@ namespace Perspex.Markup.Xaml
             yield return new Uri("resm:" + typeName + ".paml?assembly=" + asm);
 
         }
+
+        private object Load(Stream stream, object rootInstance)
+        {
+            return base.Load(stream, new Settings
+            {
+                RootInstance = rootInstance,
+                InstanceLifeCycleListener = s_lifeCycleListener,
+            });
+        }
     }
 }

src/Perspex.Base/ISupportInitialize.cs

@@ -0,0 +1,22 @@
+// Copyright (c) The Perspex Project. All rights reserved.
+// Licensed under the MIT license. See licence.md file in the project root for full license information.
+
+namespace Perspex
+{
+    /// <summary>
+    /// Specifies that this object supports a simple, transacted notification for batch 
+    /// initialization.
+    /// </summary>
+    public interface ISupportInitialize
+    {
+        /// <summary>
+        /// Signals the object that initialization is starting.
+        /// </summary>
+        void BeginInit();
+
+        /// <summary>
+        /// Signals the object that initialization is complete.
+        /// </summary>
+        void EndInit();
+    }
+}

src/Perspex.Base/Perspex.Base.csproj

@@ -55,6 +55,7 @@
     <Compile Include="DirectProperty.cs" />
     <Compile Include="IPerspexObject.cs" />
     <Compile Include="IStyledPropertyMetadata.cs" />
+    <Compile Include="ISupportInitialize.cs" />
     <Compile Include="Metadata\DependsOnAttribute.cs" />
     <Compile Include="Metadata\ContentAttribute.cs" />
     <Compile Include="PerspexDisposable.cs" />

src/Perspex.Controls/Control.cs

@@ -31,7 +31,7 @@ namespace Perspex.Controls
     /// - Implements <see cref="IStyleable"/> to allow styling to work on the control.
     /// - Implements <see cref="ILogical"/> to form part of a logical tree.
     /// </remarks>
-    public class Control : InputElement, IControl, INamed, ISetLogicalParent
+    public class Control : InputElement, IControl, INamed, ISetLogicalParent, ISupportInitialize
     {
         /// <summary>
         /// Defines the <see cref="DataContext"/> property.
@@ -84,6 +84,7 @@ namespace Perspex.Controls
         public static readonly RoutedEvent<RequestBringIntoViewEventArgs> RequestBringIntoViewEvent =
             RoutedEvent.Register<Control, RequestBringIntoViewEventArgs>("RequestBringIntoView", RoutingStrategies.Bubble);
 
+        private int _initCount;
         private string _name;
         private IControl _parent;
         private readonly Classes _classes = new Classes();
@@ -93,6 +94,7 @@ namespace Perspex.Controls
         private IPerspexList<ILogical> _logicalChildren;
         private INameScope _nameScope;
         private Styles _styles;
+        private bool _styled;
         private Subject<Unit> _styleDetach = new Subject<Unit>();
 
         /// <summary>
@@ -154,9 +156,9 @@ namespace Perspex.Controls
                     throw new InvalidOperationException("Cannot set Name to empty string.");
                 }
 
-                if (_isAttachedToLogicalTree)
+                if (_styled)
                 {
-                    throw new InvalidOperationException("Cannot set Name : control already added to tree.");
+                    throw new InvalidOperationException("Cannot set Name : control already styled.");
                 }
 
                 _name = value;
@@ -310,6 +312,28 @@ namespace Perspex.Controls
         /// <inheritdoc/>
         IStyleHost IStyleHost.StylingParent => (IStyleHost)InheritanceParent;
 
+        /// <inheritdoc/>
+        void ISupportInitialize.BeginInit()
+        {
+            ++_initCount;
+        }
+
+        /// <inheritdoc/>
+        void ISupportInitialize.EndInit()
+        {
+            if (_initCount == 0)
+            {
+                throw new InvalidOperationException("BeginInit was not called.");
+            }
+
+            if (--_initCount == 0 && !_styled)
+            {
+                RegisterWithNameScope();
+                ApplyStyling();
+                _styled = true;
+            }
+        }
+
         /// <summary>
         /// Gets a value which indicates whether a change to the <see cref="DataContext"/> is in 
         /// the process of being notified.
@@ -457,18 +481,15 @@ namespace Perspex.Controls
             // - That AttachedToLogicalTree signal travels down to the ListBoxItem
             if (!_isAttachedToLogicalTree)
             {
-                if (_nameScope == null)
-                {
-                    _nameScope = NameScope.GetNameScope(this) ?? ((Control)Parent)?._nameScope;
-                }
+                _isAttachedToLogicalTree = true;
 
-                if (Name != null)
+                if (_initCount == 0)
                 {
-                    _nameScope?.Register(Name, this);
+                    RegisterWithNameScope();
+                    ApplyStyling();
+                    _styled = true;
                 }
 
-                _isAttachedToLogicalTree = true;
-                PerspexLocator.Current.GetService<IStyler>()?.ApplyStyles(this);
                 AttachedToLogicalTree?.Invoke(this, e);
             }
 
@@ -605,6 +626,24 @@ namespace Perspex.Controls
             return null;
         }
 
+        private void ApplyStyling()
+        {
+            PerspexLocator.Current.GetService<IStyler>()?.ApplyStyles(this);
+        }
+
+        private void RegisterWithNameScope()
+        {
+            if (_nameScope == null)
+            {
+                _nameScope = NameScope.GetNameScope(this) ?? ((Control)Parent)?._nameScope;
+            }
+
+            if (Name != null)
+            {
+                _nameScope?.Register(Name, this);
+            }
+        }
+
         private static void ValidateLogicalChild(ILogical c)
         {
             if (c == null)

tests/Perspex.Controls.UnitTests/ControlTests.cs

@@ -145,6 +145,73 @@ namespace Perspex.Controls.UnitTests
             }
         }
 
+        [Fact]
+        public void Styles_Not_Applied_Until_Initialization_Finished()
+        {
+            using (PerspexLocator.EnterScope())
+            {
+                var root = new TestRoot();
+                var child = new Border();
+                var styler = new Mock<IStyler>();
+
+                PerspexLocator.CurrentMutable.Bind<IStyler>().ToConstant(styler.Object);
+
+                ((ISupportInitialize)child).BeginInit();
+                root.Child = child;
+                styler.Verify(x => x.ApplyStyles(It.IsAny<IStyleable>()), Times.Never());
+
+                ((ISupportInitialize)child).EndInit();
+                styler.Verify(x => x.ApplyStyles(child), Times.Once());
+            }
+        }
+
+        [Fact]
+        public void Adding_To_Logical_Tree_Should_Register_With_NameScope()
+        {
+            using (PerspexLocator.EnterScope())
+            {
+                var root = new TestRoot();
+                var child = new Border();
+
+                child.Name = "foo";
+                root.Child = child;
+
+                Assert.Same(root.FindControl<Border>("foo"), child);
+            }
+        }
+
+        [Fact]
+        public void Name_Cannot_Be_Set_After_Added_To_Logical_Tree()
+        {
+            using (PerspexLocator.EnterScope())
+            {
+                var root = new TestRoot();
+                var child = new Border();
+
+                root.Child = child;
+
+                Assert.Throws<InvalidOperationException>(() => child.Name = "foo");
+            }
+        }
+
+        [Fact]
+        public void Name_Can_Be_Set_While_Initializing()
+        {
+            using (PerspexLocator.EnterScope())
+            {
+                var root = new TestRoot();
+                var child = new Border();
+
+                ((ISupportInitialize)child).BeginInit();
+                root.Child = child;
+                child.Name = "foo";
+                Assert.Null(root.FindControl<Border>("foo"));
+                ((ISupportInitialize)child).EndInit();
+
+                Assert.Same(root.FindControl<Border>("foo"), child);
+            }
+        }
+
         private class TestControl : Control
         {
             public new PerspexObject InheritanceParent => base.InheritanceParent;

tests/Perspex.Markup.Xaml.UnitTests/Perspex.Markup.Xaml.UnitTests.csproj

@@ -103,7 +103,9 @@
     <Compile Include="SamplePerspexObject.cs" />
     <Compile Include="StyleTests.cs" />
     <Compile Include="Templates\DataTemplateTests.cs" />
+    <Compile Include="Xaml\BasicTests.cs" />
     <Compile Include="Xaml\BindingTests.cs" />
+    <Compile Include="Xaml\InitializationOrderTracker.cs" />
     <Compile Include="Xaml\NonControl.cs" />
     <Compile Include="Xaml\TreeDataTemplateTests.cs" />
     <Compile Include="TypeProviderMock.cs" />