extjs 点击树tabpanel不出来

Question

分成两个写的
Ext.define('MyApp.view.MyPanel', {
extend: 'Ext.panel.Panel',
alias: 'widget.mypanel',

requires: [
    'MyApp.view.MyPanelViewModel',
    'MyApp.view.MyPanelViewController',
    'Ext.tree.Panel',
    'Ext.tree.View',
    'Ext.tab.Panel'
],

controller: 'mypanel',
viewModel: {
    type: 'mypanel'
},
height: 634,
id: 'mainpanel',
width: 1001,
layout: 'border',
title: 'My Panel',

items: [
    {
        xtype: 'treepanel',
        region: 'west',
        split: true,
        width: 150,
        collapsible: true,
        title: '菜单栏',
        store: 'MyTreeStore',
        rootVisible: false,
        listeners: {
            itemclick: 'itemclick'
        }
    },
    {
        xtype: 'tabpanel',
        region: 'center',
        html: '不将就',
        itemId: 'tab-3',
        title: '欢迎',
        titleCollapse: false,
        listeners: {
            tabchange: 'tabchange'
        }
    }
]

});
还有事件：
Ext.define('MyApp.view.MyPanelViewController', {
extend: 'Ext.app.ViewController',
alias: 'controller.mypanel',

itemclick: function(dataview, record, item, index, e, eOpts) {
    //console.log(this.getRootNode().childNodes[index].data);
    var json = record.data;
    Ext.getCmp(mainpanel).down('tabpanel');
    var tab = tabs.child('#tab-'+json.id);
    // 是否添加
    if(!tab){
        tab = Ext.create('Ext.tab.Tab',{itemId:'tab-'+json.id,title:json.text,html:'第'+json.id+'显示'});
        //tab = {itemId:'tab-'+json.id,title:json.text,html:'fff'};
        tabs.add(tab);
    }
    //  激活
    tabs.setActiveTab(tab);
},

tabchange: function(tabPanel, newCard, oldCard, eOpts) {
    //  关联树操作
    Ext.getCmp(manelpanel).down('treepanel');
    // 非空
    if(newCard.itemId){

        var sp = newCard.itemId.split('-');
        var xpath = '';
        // 组成 path
        for(var i = 1 ; i < sp.length-1 ; i++){
            xpath += sp[i]+'/';
        }
        // 最后值
        var last = sp.join('-').replace('tab-','');
        // 选择 tree
        tree.selectPath('/root/'+xpath+last);
    }
}

});