Update more-routing for md-settings

third_party/polymer/v0_8/components/more-routing/more-route-selector.html

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 <link rel="import" href="../polymer/polymer.html">
 
@@ skipping 109 matching lines @@
     this._updateRoutes();
   },
 
   /**
    * Handle a change in selected item, driven by the targeted selector.
    *
    * Note that this will fail if a route is chosen that requires params not
    * defined by the current URL.
    */
   _onSelectedItemChanged: function(event) {
+    if (this._settingSelection) return;
     var route = this._routeForItem(event.detail.value);
     if (!route) return;
     route.navigateTo();
   },
 
   _updateRoutes: function() {
     var routes = [];
     if (this._managedSelector) {
       routes = this._managedSelector.items.map(this._routeForItem.bind(this));
     }
     this._setRoutes(routes);
   },
 
   _onMoreRouteChange: function(event) {
     if (!this._managedSelector) return;
-    var route = event.detail.newRoute;
-    this._managedSelector.select(this.routes.indexOf(route));
+
+    var selected = '';
+
+    var index = this.routes.indexOf(event.detail.newRoute);
+    var attrForSelected = this._managedSelector.attrForSelected;
+    if (!attrForSelected) {
+      selected = index;
+    } else {
+      var item = this._managedSelector.items[index];
+      if (item)
+        selected = item[attrForSelected] || item.getAttribute(attrForSelected);
+    }
+
+    // Make sure that we don't turn around and re-navigate
+    this._settingSelection = true;
+    this._managedSelector.select(selected);
+    this._settingSelection = false;
   },
 
   _findTargetSelector: function() {
     var children = Polymer.dom(this).children;
     if (children.length !== 1) {
       console.error(this, 'expects only a single selector child');
       return null;
     }
 
     var child = children[0];
@@ skipping 18 matching lines @@
     var expression = item.getAttribute(this.routeAttribute);
     var route      = MoreRouting.getRoute(expression, this.parentRoute);
     // Associate the route w/ its element while we're here.
     item.moreRouteContext = route;
 
     return route;
   },
 
 });
 </script>