wip abstracting more things

Author: shana

src/GitHub.Exports/Services/IVSUIContext.cs

@@ -1,6 +1,5 @@
 using Microsoft.VisualStudio.Shell;
 using System;
-using System.ComponentModel.Composition;
 
 namespace GitHub.Services
 {
@@ -9,43 +8,14 @@ public interface IVSUIContextFactory
         IVSUIContext GetUIContext(Guid contextGuid);
     }
 
-    [Export(typeof(IVSUIContextFactory))]
-    [PartCreationPolicy(CreationPolicy.Shared)]
-    public class VSUIContextFactory : IVSUIContextFactory
+    public interface IVSUIContextChangedEventArgs
     {
-        public IVSUIContext GetUIContext(Guid contextGuid)
-        {
-            return new VSUIContext(UIContext.FromUIContextGuid(contextGuid));
-        }
+        bool Activated { get; }
     }
 
     public interface IVSUIContext
     {
         bool IsActive { get; }
-        event EventHandler<UIContextChangedEventArgs> UIContextChanged;
-    }
-
-    public class VSUIContext : IVSUIContext
-    {
-        readonly UIContext context;
-
-        public VSUIContext(UIContext context)
-        {
-            this.context = context;
-        }
-
-        public bool IsActive { get { return context.IsActive; } }
-
-        public event EventHandler<UIContextChangedEventArgs> UIContextChanged
-        {
-            add
-            {
-                context.UIContextChanged += value;
-            }
-            remove
-            {
-                context.UIContextChanged -= value;
-            }
-        }
+        event EventHandler<IVSUIContextChangedEventArgs> UIContextChanged;
     }
 }

src/GitHub.TeamFoundation.14/Base/TeamExplorerServiceHolder.cs

@@ -21,7 +21,7 @@ namespace GitHub.VisualStudio.Base
     public class TeamExplorerServiceHolder : ITeamExplorerServiceHolder
     {
         static readonly ILogger log = LogManager.ForContext<TeamExplorerServiceHolder>();
-        readonly IVSUIContextFactory uiContextFactory;
+        readonly IVSUIContextFactory uiContextFactory = null;
         readonly Dictionary<object, Action<ILocalRepositoryModel>> activeRepoHandlers = new Dictionary<object, Action<ILocalRepositoryModel>>();
         ILocalRepositoryModel activeRepo;
         bool activeRepoNotified = false;
@@ -33,9 +33,12 @@ public class TeamExplorerServiceHolder : ITeamExplorerServiceHolder
         // ActiveRepositories PropertyChanged event comes in on a non-main thread
         readonly SynchronizationContext syncContext;
 
-        public TeamExplorerServiceHolder(IVSUIContextFactory uiContextFactory, IVSGitExt gitService)
+        [ImportingConstructor]
+        //public TeamExplorerServiceHolder(IVSUIContextFactory uiContextFactory, IVSGitExt gitService)
+        public TeamExplorerServiceHolder(IVSGitExt gitService)
         {
-            this.uiContextFactory = uiContextFactory;
+            Debugger.Break();
+            //this.uiContextFactory = uiContextFactory;
             this.GitService = gitService;
             syncContext = SynchronizationContext.Current;
         }
@@ -80,7 +83,7 @@ public void Subscribe(object who, Action<ILocalRepositoryModel> handler)
 
             bool notificationsExist;
             ILocalRepositoryModel repo;
-            lock(activeRepoHandlers)
+            lock (activeRepoHandlers)
             {
                 repo = ActiveRepo;
                 notificationsExist = activeRepoNotified;
@@ -142,7 +145,7 @@ void NotifyActiveRepo()
             }
         }
 
-        void UIContextChanged(object sender, UIContextChangedEventArgs e)
+        void UIContextChanged(object sender, IVSUIContextChangedEventArgs e)
         {
             Guard.ArgumentNotNull(e, nameof(e));
 
@@ -247,6 +250,68 @@ IVSGitExt GitService
         }
     }
 
+        [Export(typeof(IVSUIContextFactory))]
+        [PartCreationPolicy(CreationPolicy.Shared)]
+        public class VSUIContextFactory : IVSUIContextFactory
+        {
+            [ImportingConstructor]
+            public VSUIContextFactory()
+            {
+                Debugger.Break();
+            }
+
+            public IVSUIContext GetUIContext(Guid contextGuid)
+            {
+                return new VSUIContext(UIContext.FromUIContextGuid(contextGuid));
+            }
+        }
+
+        public class VSUIContextChangedEventArgs : IVSUIContextChangedEventArgs
+        {
+            public bool Activated { get; }
+
+            public VSUIContextChangedEventArgs(bool activated)
+            {
+                Activated = activated;
+            }
+        }
+
+        public class VSUIContext : IVSUIContext
+        {
+            readonly UIContext context;
+            readonly Dictionary<EventHandler<IVSUIContextChangedEventArgs>, EventHandler<UIContextChangedEventArgs>> handlers =
+                new Dictionary<EventHandler<IVSUIContextChangedEventArgs>, EventHandler<UIContextChangedEventArgs>>();
+            public VSUIContext(UIContext context)
+            {
+                this.context = context;
+            }
+
+            public bool IsActive { get { return context.IsActive; } }
+
+            public event EventHandler<IVSUIContextChangedEventArgs> UIContextChanged
+            {
+                add
+                {
+                    EventHandler<UIContextChangedEventArgs> handler = null;
+                    if (!handlers.TryGetValue(value, out handler))
+                    {
+                        handler = (s, e) => value.Invoke(s, new VSUIContextChangedEventArgs(e.Activated));
+                        handlers.Add(value, handler);
+                    }
+                    context.UIContextChanged += handler;
+                }
+                remove
+                {
+                    EventHandler<UIContextChangedEventArgs> handler = null;
+                    if (handlers.TryGetValue(value, out handler))
+                    {
+                        handlers.Remove(value);
+                        context.UIContextChanged -= handler;
+                    }
+                }
+            }
+        }
+
     static class IGitRepositoryInfoExtensions
     {
         /// <summary>