Added manuallyHandleUpdateEvents and documented usage.

README.md

@@ -526,7 +526,7 @@ The sortable/draggable bindingHandlers supports the same syntax as Knockouts bui
 Other attributes are:
 *	options: an object that contains settings for the underlaying sortable, ie `group`,`handle`, events etc.
 *	collection: if your `foreach` array is a computed then you would supply the underlaying observableArray that you would like to sort here.
-
+*   manuallyHandleUpdateEvents: a boolean to turn off the change events on update that other polymer elements listen to.
 
 ---
 

Sortable.html

@@ -30,6 +30,7 @@
       forceFallback               : { type: Boolean, value: false, observer: "forceFallbackChanged" },
       fallbackClass               : { type: String, value: "sortable-fallback", observer: "fallbackClassChanged" },
       fallbackOnBody              : { type: Boolean, value: false, observer: "fallbackOnBodyChanged" },
+      manuallyHandleUpdateEvents  : { type: Boolean, value: false },
       draggable                   : {},
       scroll                      : {}
     },
@@ -78,7 +79,11 @@
       this.sortable = Sortable.create(this, Object.assign(options, {
         onUpdate: e => {
           if (template) {
+            if(manuallyHandleUpdateEvents) {
               template.items.splice(e.newIndex, 0, template.items.splice(e.oldIndex, 1)[0]);
+            } else {
+              template.splice("items", e.newIndex, 0, template.splice("items", e.oldIndex, 1)[0])
+            }
           }
           this.fire("update", e)
         },