Index: Core/Plugins/src/Core.Plugins.Map/Legend/MapLegendView.cs
===================================================================
diff -u -r7a02214c204a80a085b50b8d5fd7f90b9e0b4149 -rd481a5ba0fb5309250e76a7e8dc12a512a6d3312
--- Core/Plugins/src/Core.Plugins.Map/Legend/MapLegendView.cs	(.../MapLegendView.cs)	(revision 7a02214c204a80a085b50b8d5fd7f90b9e0b4149)
+++ Core/Plugins/src/Core.Plugins.Map/Legend/MapLegendView.cs	(.../MapLegendView.cs)	(revision d481a5ba0fb5309250e76a7e8dc12a512a6d3312)
@@ -120,7 +120,7 @@
                 CanDrag = (mapPointData, parentData) => true,
                 CanCheck = mapPointData => true,
                 IsChecked = mapPointData => mapPointData.IsVisible,
-                OnNodeChecked = PointBasedMapDataOnNodeChecked
+                OnNodeChecked = MapDataOnNodeChecked
             });
 
             treeViewControl.RegisterTreeNodeInfo(new TreeNodeInfo<MapLineData>
@@ -133,7 +133,7 @@
                 CanDrag = (mapLineData, parentData) => true,
                 CanCheck = mapLineData => true,
                 IsChecked = mapLineData => mapLineData.IsVisible,
-                OnNodeChecked = PointBasedMapDataOnNodeChecked
+                OnNodeChecked = MapDataOnNodeChecked
             });
 
             treeViewControl.RegisterTreeNodeInfo(new TreeNodeInfo<MapPolygonData>
@@ -146,7 +146,7 @@
                 CanDrag = (mapPolygonData, parentData) => true,
                 CanCheck = mapPolygonData => true,
                 IsChecked = mapPolygonData => mapPolygonData.IsVisible,
-                OnNodeChecked = PointBasedMapDataOnNodeChecked
+                OnNodeChecked = MapDataOnNodeChecked
             });
 
             treeViewControl.RegisterTreeNodeInfo(new TreeNodeInfo<MapDataCollection>
@@ -163,16 +163,10 @@
 
         #region MapData
 
-        private static void PointBasedMapDataOnNodeChecked(FeatureBasedMapData featureBasedMapData, object parentData)
+        private static void MapDataOnNodeChecked(FeatureBasedMapData featureBasedMapData, object parentData)
         {
             featureBasedMapData.IsVisible = !featureBasedMapData.IsVisible;
             featureBasedMapData.NotifyObservers();
-
-            var observableParent = parentData as IObservable;
-            if (observableParent != null)
-            {
-                observableParent.NotifyObservers();
-            }
         }
 
         #endregion
Index: Core/Plugins/test/Core.Plugins.Map.Test/Legend/MapLineDataTreeNodeInfoTest.cs
===================================================================
diff -u -r6ab9f58d961acb9f1f80fab04e8759b9990262e0 -rd481a5ba0fb5309250e76a7e8dc12a512a6d3312
--- Core/Plugins/test/Core.Plugins.Map.Test/Legend/MapLineDataTreeNodeInfoTest.cs	(.../MapLineDataTreeNodeInfoTest.cs)	(revision 6ab9f58d961acb9f1f80fab04e8759b9990262e0)
+++ Core/Plugins/test/Core.Plugins.Map.Test/Legend/MapLineDataTreeNodeInfoTest.cs	(.../MapLineDataTreeNodeInfoTest.cs)	(revision d481a5ba0fb5309250e76a7e8dc12a512a6d3312)
@@ -180,39 +180,23 @@
 
         [TestCase(true)]
         [TestCase(false)]
-        public void OnNodeChecked_LineDataNodeWithoutParent_SetsLineDataVisibility(bool initialVisibleState)
+        public void OnNodeChecked_MapLineDataNode_SetsLineDataVisibilityAndNotifiesObservers(bool initialVisibleState)
         {
             // Setup
-            mocks.ReplayAll();
-            var mapLineData = new MapLineData("test data")
-            {
-                IsVisible = initialVisibleState
-            };
+            var observer = mocks.StrictMock<IObserver>();
+            observer.Expect(o => o.UpdateObserver());
 
-            // Call
-            info.OnNodeChecked(mapLineData, null);
-
-            // Assert
-            Assert.AreEqual(!initialVisibleState, mapLineData.IsVisible);
-        }
-
-        [TestCase(true)]
-        [TestCase(false)]
-        public void OnNodeChecked_LineDataNodeWithObservableParent_SetsLineDataVisibilityAndNotifiesParentObservers(bool initialVisibleState)
-        {
-            // Setup
-            var observable = mocks.StrictMock<IObservable>();
-            observable.Expect(o => o.NotifyObservers());
-
             mocks.ReplayAll();
 
             var mapLineData = new MapLineData("test data")
             {
                 IsVisible = initialVisibleState
             };
 
+            mapLineData.Attach(observer);
+
             // Call
-            info.OnNodeChecked(mapLineData, observable);
+            info.OnNodeChecked(mapLineData, null);
 
             // Assert
             Assert.AreEqual(!initialVisibleState, mapLineData.IsVisible);
Index: Core/Plugins/test/Core.Plugins.Map.Test/Legend/MapPointDataTreeNodeInfoTest.cs
===================================================================
diff -u -r6ab9f58d961acb9f1f80fab04e8759b9990262e0 -rd481a5ba0fb5309250e76a7e8dc12a512a6d3312
--- Core/Plugins/test/Core.Plugins.Map.Test/Legend/MapPointDataTreeNodeInfoTest.cs	(.../MapPointDataTreeNodeInfoTest.cs)	(revision 6ab9f58d961acb9f1f80fab04e8759b9990262e0)
+++ Core/Plugins/test/Core.Plugins.Map.Test/Legend/MapPointDataTreeNodeInfoTest.cs	(.../MapPointDataTreeNodeInfoTest.cs)	(revision d481a5ba0fb5309250e76a7e8dc12a512a6d3312)
@@ -180,39 +180,23 @@
 
         [TestCase(true)]
         [TestCase(false)]
-        public void OnNodeChecked_PointDataNodeWithoutParent_SetsPointDataVisibility(bool initialVisibleState)
+        public void OnNodeChecked_MapPointDataNode_SetsPointDataVisibilityAndNotifiesObservers(bool initialVisibleState)
         {
             // Setup
-            mocks.ReplayAll();
-            var mapPointData = new MapPointData("test data")
-            {
-                IsVisible = initialVisibleState
-            };
+            var observer = mocks.StrictMock<IObserver>();
+            observer.Expect(o => o.UpdateObserver());
 
-            // Call
-            info.OnNodeChecked(mapPointData, null);
-
-            // Assert
-            Assert.AreEqual(!initialVisibleState, mapPointData.IsVisible);
-        }
-
-        [TestCase(true)]
-        [TestCase(false)]
-        public void OnNodeChecked_PointDataNodeWithObservableParent_SetsPointDataVisibilityAndNotifiesParentObservers(bool initialVisibleState)
-        {
-            // Setup
-            var observable = mocks.StrictMock<IObservable>();
-            observable.Expect(o => o.NotifyObservers());
-
             mocks.ReplayAll();
 
             var mapPointData = new MapPointData("test data")
             {
                 IsVisible = initialVisibleState
             };
 
+            mapPointData.Attach(observer);
+
             // Call
-            info.OnNodeChecked(mapPointData, observable);
+            info.OnNodeChecked(mapPointData, null);
 
             // Assert
             Assert.AreEqual(!initialVisibleState, mapPointData.IsVisible);
Index: Core/Plugins/test/Core.Plugins.Map.Test/Legend/MapPolygonDataTreeNodeInfoTest.cs
===================================================================
diff -u -r6ab9f58d961acb9f1f80fab04e8759b9990262e0 -rd481a5ba0fb5309250e76a7e8dc12a512a6d3312
--- Core/Plugins/test/Core.Plugins.Map.Test/Legend/MapPolygonDataTreeNodeInfoTest.cs	(.../MapPolygonDataTreeNodeInfoTest.cs)	(revision 6ab9f58d961acb9f1f80fab04e8759b9990262e0)
+++ Core/Plugins/test/Core.Plugins.Map.Test/Legend/MapPolygonDataTreeNodeInfoTest.cs	(.../MapPolygonDataTreeNodeInfoTest.cs)	(revision d481a5ba0fb5309250e76a7e8dc12a512a6d3312)
@@ -180,39 +180,23 @@
 
         [TestCase(true)]
         [TestCase(false)]
-        public void OnNodeChecked_PolygonDataNodeWithoutParent_SetsPolygonDataVisibility(bool initialVisibleState)
+        public void OnNodeChecked_MapPolygonDataNode_SetsPolygonDataVisibilityAndNotifiesObservers(bool initialVisibleState)
         {
             // Setup
-            mocks.ReplayAll();
-            var mapPolygonData = new MapPolygonData("test data")
-            {
-                IsVisible = initialVisibleState
-            };
+            var observer = mocks.StrictMock<IObserver>();
+            observer.Expect(o => o.UpdateObserver());
 
-            // Call
-            info.OnNodeChecked(mapPolygonData, null);
-
-            // Assert
-            Assert.AreEqual(!initialVisibleState, mapPolygonData.IsVisible);
-        }
-
-        [TestCase(true)]
-        [TestCase(false)]
-        public void OnNodeChecked_PolygonDataNodeWithObservableParent_SetsPolygonDataVisibilityAndNotifiesParentObservers(bool initialVisibleState)
-        {
-            // Setup
-            var observable = mocks.StrictMock<IObservable>();
-            observable.Expect(o => o.NotifyObservers());
-
             mocks.ReplayAll();
 
             var mapPolygonData = new MapPolygonData("test data")
             {
                 IsVisible = initialVisibleState
             };
 
+            mapPolygonData.Attach(observer);
+
             // Call
-            info.OnNodeChecked(mapPolygonData, observable);
+            info.OnNodeChecked(mapPolygonData, null);
 
             // Assert
             Assert.AreEqual(!initialVisibleState, mapPolygonData.IsVisible);