use the bind function to pass context

UI.Web.Dashboard/src/pages/home/home.js

@@ -37,21 +37,20 @@ define([
   }
 
   HomeViewModel.prototype.refresh = function () {
-    var that = this;
     this.isRefreshing(true);
-    this.queryHandler.handle().then(function(data) {
-      var sensorsGroupedByName = _.groupBy(data, "name")
-      _.each(sensorsGroupedByName, function(sensorReadings, key){
+    this.queryHandler.handle().then(_.bind(function(data) {
+      var sensorsGroupedByName = _.groupBy(data, "name");
+      _.each(sensorsGroupedByName, _.bind(function(sensorReadings, key){
           var latestReading = _.orderBy(sensorReadings, "timestamp").pop();
 
-          if(that.sensorsDict[key]){
-            that.updateSensor(key, latestReading);
+          if(this.sensorsDict[key]){
+            this.updateSensor(key, latestReading);
           } else {
-            that.addSensor(key, latestReading);
+            this.addSensor(key, latestReading);
           }
-      })
-      that.isRefreshing(false);
-    })
+      }, this));
+      this.isRefreshing(false);
+    }, this));
   }
 
   return { viewModel: HomeViewModel, template: homeTemplate };