--- a/client/js/renderer/basebutton.js	Thu Jun 18 16:54:57 2015 +0200
+++ b/client/js/renderer/basebutton.js	Thu Jun 18 17:17:11 2015 +0200
@@ -18,7 +18,9 @@
             this.sector.show();
         },
         hide: function() {
-            this.sector.hide();
+            if (this.sector){
+                this.sector.hide();                
+            }
         },
         select: function() {
             this.sector.select();