Fixed updating of the IWorkbench.ActiveWorkbenchWindow property.

This fixes the bug "System.NullReferenceException in AvalonDock.DocumentContent.Close()"

git-svn-id: svn://svn.sharpdevelop.net/sharpdevelop/trunk@5536 1ccf3a8d-04fe-1044-b7c0-cef0b8235c61

src/Main/Base/Project/Src/Gui/IWorkbenchLayout.cs

@@ -40,6 +40,7 @@ namespace ICSharpCode.SharpDevelop.Gui
 			get;
 		}
 		
+		event EventHandler ActiveWorkbenchWindowChanged;
 		event EventHandler ActiveContentChanged;
 		
 		/// <summary>

src/Main/Base/Project/Src/Gui/Workbench/Layouts/AvalonDockLayout.cs

@@ -63,27 +63,26 @@ namespace ICSharpCode.SharpDevelop.Gui
 		void dockingManager_PropertyChanged(object sender, System.ComponentModel.PropertyChangedEventArgs e)
 		{
 			if (e.PropertyName == "ActiveContent") {
-				UpdateActiveWorkbenchWindow();
 				if (ActiveContentChanged != null)
 					ActiveContentChanged(this, e);
 				CommandManager.InvalidateRequerySuggested();
 			} else if (e.PropertyName == "ActiveDocument") {
-				UpdateActiveWorkbenchWindow();
+				if (ActiveWorkbenchWindowChanged != null)
+					ActiveWorkbenchWindowChanged(this, e);
 				CommandManager.InvalidateRequerySuggested();
 			}
 		}
 		
-		public event EventHandler ActiveContentChanged;
-		
-		public IWorkbenchWindow ActiveWorkbenchWindow { get; private set; }
+		public event EventHandler ActiveWorkbenchWindowChanged;
 		
-		void UpdateActiveWorkbenchWindow()
-		{
-			IWorkbenchWindow window = dockingManager.ActiveDocument as IWorkbenchWindow;
-			if (window != null)
-				this.ActiveWorkbenchWindow = window;
+		public IWorkbenchWindow ActiveWorkbenchWindow { 
+			get {
+				return dockingManager.ActiveDocument as IWorkbenchWindow;
+			}
 		}
 		
+		public event EventHandler ActiveContentChanged;
+		
 		public object ActiveContent {
 			get {
 				object activeContent = dockingManager.ActiveContent;
@@ -240,10 +239,6 @@ namespace ICSharpCode.SharpDevelop.Gui
 		void window_Closed(object sender, EventArgs e)
 		{
 			workbenchWindows.Remove((IWorkbenchWindow)sender);
-			if (this.ActiveWorkbenchWindow == sender) {
-				this.ActiveWorkbenchWindow = null;
-				UpdateActiveWorkbenchWindow();
-			}
 		}
 		
 		public void LoadConfiguration()

src/Main/Base/Project/Src/Gui/WorkbenchSingleton.cs

@@ -89,12 +89,15 @@ namespace ICSharpCode.SharpDevelop.Gui
 			NavigationService.InitializeService();
 			
 			workbench.ActiveContentChanged += delegate {
+				Debug.WriteLine("ActiveContentChanged to " + workbench.ActiveContent);
 				LoggingService.Debug("ActiveContentChanged to " + workbench.ActiveContent);
 			};
 			workbench.ActiveViewContentChanged += delegate {
+				Debug.WriteLine("ActiveViewContentChanged to " + workbench.ActiveViewContent);
 				LoggingService.Debug("ActiveViewContentChanged to " + workbench.ActiveViewContent);
 			};
 			workbench.ActiveWorkbenchWindowChanged += delegate {
+				Debug.WriteLine("ActiveWorkbenchWindowChanged to " + workbench.ActiveWorkbenchWindow);
 				LoggingService.Debug("ActiveWorkbenchWindowChanged to " + workbench.ActiveWorkbenchWindow);
 			};
 		}