diff --git a/controllets/tree-view-controllet/demo/index.html b/controllets/tree-view-controllet/demo/index.html
old mode 100644
new mode 100755
index 0f97565..85ae214
--- a/controllets/tree-view-controllet/demo/index.html
+++ b/controllets/tree-view-controllet/demo/index.html
@@ -53,8 +53,8 @@
 
         tree.addEventListener("tree-view-controllet_selected-fields", function (e) {
             fields.innerHTML = e.detail.fields;
-            console.log(tree.getFlatFields());
-            console.log(tree.getFields());//firefox console.log does not recognize associative array?
+//            console.log(tree.getFlatFields());
+//            console.log(tree.getFields());//firefox console.log does not recognize associative array?
         });
 
     </script>
@@ -64,6 +64,7 @@
 </html>
 
 <!--urls:-->
+<!--http://dati.lazio.it/catalog/api/action/datastore_search?resource_id=114baf3d-6d4f-42ff-b4af-481beef59ae1-->
 <!--url: 'http://ckan.routetopa.eu/api/action/datastore_search?resource_id=73e02092-85a1-434e-85fe-0c9a43aa9a52&limit=5',-->
 <!--url: 'https://data.issy.com/api/records/1.0/search?dataset=liste-des-restaurants-a-issy-les-moulineaux&sort=type&facet=type&facet=terrasse',-->
 <!--url: 'https://data.issy.com/api/records/1.0/search?dataset=flux-rss-des-offres-demplois-a-issy-les-moulineaux&sort=published&facet=published&refine.published=2015',-->
diff --git a/controllets/tree-view-controllet/tree-view-controllet.html b/controllets/tree-view-controllet/tree-view-controllet.html
old mode 100644
new mode 100755
index c9b6707..7580c69
--- a/controllets/tree-view-controllet/tree-view-controllet.html
+++ b/controllets/tree-view-controllet/tree-view-controllet.html
@@ -8,7 +8,6 @@
 <dom-module id="tree-view-controllet">
 
     <style is="custom-style">
-
         --paper-item {
         }
 
@@ -36,7 +35,7 @@
 
         :host{
             --paper-menu-focused-item-after: {
-                opacity: 0;
+                 opacity: 0;
             };
         }
     </style>
@@ -131,7 +130,10 @@
 
             _createTree : function(nodeName, node) {
                 var html = "";
-                if(node.constructor == Object){
+                if(!node){
+                    html = nodeName;
+                }
+                else if(node.constructor == Object){
                     var list  = new Array();
                     for(var child in node)
                         list.push(this._createTree(nodeName+","+child, node[child]));
@@ -237,6 +239,7 @@
             },
 
             _updateSelectedFields : function(e) {
+
                 var menuId = e.target.id;
                 var selectedIds = [];
 
@@ -247,12 +250,22 @@
                         selectedIds.push(id);
                 }
 
-                if(selectedIds.length)
-                    this.selectedFields[menuId] = selectedIds;
+                var prevLength;
+                if(this.selectedFields[menuId])
+                    prevLength = this.selectedFields[menuId].length;
                 else
-                    delete this.selectedFields[menuId];
+                    prevLength = 0;
+                var currLength = selectedIds.length
 
-                this.fire('tree-view-controllet_selected-fields', {fields : this.getFlatFields()});
+                if(prevLength != currLength) {
+
+                    if (selectedIds.length)
+                        this.selectedFields[menuId] = selectedIds;
+                    else
+                        delete this.selectedFields[menuId];
+
+                    this.fire('tree-view-controllet_selected-fields', {fields: this.getFlatFields()});
+                }
             }
 
         });