Ext.Viewport.setActiveItem does not work after upgrading from 2.0.1 to 2.1

[fuchsi]

Hi!

I'm new to Sencha Touch and i'm working on my first bigger App. I started with Sencha Touch 2.0.1 and wanted to upgrade to 2.1 and Sencha cmd. But after upgrading my navigation isn't working in my App. I'm using Ext.Viewport.setActiveItem and redirects for Android to navigate through my app.

first view:

Ext.define("Myapp.view.opponents.Start", {    extend: 'Ext.Container',
    alias: 'widget.opponents_start_view',
    config:{
        fullscreen: true,
        items:
        [
        {
        xtype: 'titlebar',
                docked: 'top',
                title: 'Online or Offline',
                items:[
                    {
                        xtype: "button",
                        ui: "back",
                        text: "Home",
                        itemId: "back_to_home",
                        
                    }
                ]
       },
       
       {
            xtype : 'container',
            centered: true,
            layout : {
                type : 'vbox',
                align : 'center',
                pack : 'center'
                    },


                items : [{
                    xtype : 'button',
                    text : 'Online',
                    itemId : 'online_game',
                    margin : 3,
                    disabled: true
                }, 
                {
                    xtype : 'button',
                    text : 'Offline',
                    itemId : 'offline_game',
                    margin : 3
                }],
        }
        ]
    }
});

third view:

Ext.define("Myapp.view.Offline_game", {    
    extend: 'Ext.Container',
    alias: 'widget.offline_game_view',
    xtype: 'offline_game_view',    
    layout: {
        type: 'vbox',
        
    },
    config:{
        fullscreen: true,
        scrollable: {
        direction: 'vertical'
        },
        items:
        [
            {
                //titlebar
                xtype: 'titlebar',
                docked: 'top',
                itemId: 'title',
                title:    'Offline',
                items:
                [
                    {
                        xtype: "button",
                        ui: "back",
                        text: "Back",
                        itemId: "backButton"
                    }
                ]
            },
            {
             
                        xtype: "button",
                        text: "testbutton",
                        itemId: "testbutton"
                    }
            ]}                        
    });

the controllers in the same order:

Ext.define('Myapp.controller.opponents.Start', {    extend: 'Ext.app.Controller',
    config:{
        routes:{
            'opponents/Start': 'init_opponents_Start'
        },
        control:{
            'opponents_start_view #back_to_home':{
                tap: 'on_back_home'
            },
            'opponents_start_view #offline_game':{
                tap:'on_offline_game'
            }
        }
    },
    
    init_opponents_Start: function(){
        Ext.Viewport.setActiveItem(Ext.create('Cross-SteinScherePapier.view.opponents.Start'));
    },
    
    on_back_home: function(){
        this.redirectTo('Start');
    },
    
    on_offline_game: function(){
        this.redirectTo('Offline_game');
    }
 });

Ext.define('Myapp.controller.Offline_game', {    extend : 'Ext.app.Controller',
    config : {
        routes:{
            'Offline_game': 'init_offline_game'
        },
        refs: {    
            offline_game_view: 'offline_game_view',
                    
        },
        },
    
    
    onback_offline_game: function(){
    },
    
    init_offline_game: function(){
            Ext.Viewport.setActiveItem(Ext.create('Myapp.view.Offline_game'));
    }
});

When i click on the Offline_game button i get this error in the browser: Uncaught TypeError: Object #<Object> has no method 'onItemAdd'.
This error occurs in the Container.js line 1075

Can you help me please.

[fuchsi]

Can anybody help me please?