how to load a toolbar item from a json store

[only_do@126.com]

how to load toolbar items from a json store?
this is my json return:

{"data":[{"text":"refresh","iconCls":"icon-refresh","id":"1"}],"size":1}

and this is the jsonstore define

this.tbstore=new Ext.data.JsonStore({      
      autoDestroy: true,
      autoLoad:true,
      url: 'user/test.do',
      root: 'data',
      idProperty: 'id',
      fields: [ 'id','text', 'iconCls']
  });

can i load these items after a panel initComponent?

[jay@moduscreate.com]

Why create a JSON store for one item?