From 9ee2fde44e4dc5b7df49fe0970ac78d916b86fde Mon Sep 17 00:00:00 2001
From: Aleksandar Toplek <aleksandar.toplek@gmail.com>
Date: Thu, 1 Dec 2016 15:55:47 +0100
Subject: [PATCH] Fixed WPF example layer changed handler

---
 SharpMap.UI.WPF/SharpMapHost.cs | 28 ++++++++++++++++------------
 1 file changed, 16 insertions(+), 12 deletions(-)

diff --git a/SharpMap.UI.WPF/SharpMapHost.cs b/SharpMap.UI.WPF/SharpMapHost.cs
index 5aef4080..ff956d29 100644
--- a/SharpMap.UI.WPF/SharpMapHost.cs
+++ b/SharpMap.UI.WPF/SharpMapHost.cs
@@ -403,29 +403,33 @@ private void OnMapLayerChanged(object sender, NotifyCollectionChangedEventArgs e
             switch (e.Action)
             {
                 case NotifyCollectionChangedAction.Add:
-                {
-                    var layers = sender as ObservableCollection<ILayer>;
-                    if (layers != null)
                     {
-                        foreach (var layer in layers.Where(layer => !_mapBox.Map.Layers.Contains(layer)))
+                        var layers = e.NewItems;
+                        if (layers != null)
                         {
-                            _mapBox.Map.Layers.Add(layer);
+                            foreach (var layer in layers)
+                            {
+                                var castedLayer = layer as ILayer;
+                                if (castedLayer != null && MapBox.Map.Layers.All(l => l.LayerName != castedLayer.LayerName))
+                                    MapBox.Map.Layers.Add(castedLayer);
+                            }
                         }
                     }
-                }
 
                     break;
                 case NotifyCollectionChangedAction.Remove:
-                {
-                    var layers = sender as ObservableCollection<ILayer>;
-                    if (layers != null)
                     {
-                        foreach (var layer in layers.Where(layer => _mapBox.Map.Layers.Contains(layer)))
+                        var layers = e.OldItems;
+                        if (layers != null)
                         {
-                            _mapBox.Map.Layers.Remove(layer);
+                            foreach (var layer in layers)
+                            {
+                                var castedLayer = layer as ILayer;
+                                if (castedLayer != null && MapBox.Map.Layers.Any(l => l.LayerName == castedLayer.LayerName))
+                                    MapBox.Map.Layers.Remove(castedLayer);
+                            }
                         }
                     }
-                }
 
                     break;
                 case NotifyCollectionChangedAction.Reset: