diff --git a/src/components/ion.js b/src/components/ion.js
index 71c417e0ba..3c0f9eecca 100644
--- a/src/components/ion.js
+++ b/src/components/ion.js
@@ -3,7 +3,7 @@ var ILLEGAL_ASSIGN_FIELDS = {};
 export class Ion {
 
   assign() {
-    for (var i = 1, ii = arguments.length; i < ii; i++) {
+    for (var i = 0, ii = arguments.length; i < ii; i++) {
       var obj = arguments[i];
       if (obj) {
         var keys = Object.keys(obj);
diff --git a/src/components/tabbar/tabbar.js b/src/components/tabbar/tabbar.js
index 49b2d322a1..70719c7b10 100644
--- a/src/components/tabbar/tabbar.js
+++ b/src/components/tabbar/tabbar.js
@@ -8,7 +8,16 @@ import {Ion} from '../ion';
   }
 })
 @Template({
-  inline: `<div>Tabbar: {{title}}</div>`
+  inline: `<button (click)="press()">Tabbar: {{title}}</button>`
 })
 export class Tabbar extends Ion {
+  constructor() {
+
+    // Test that Ion#assign works
+    this.assign({
+      press: () => {
+        alert('pressed!');
+      }
+    });
+  }
 }