display a hidden item in a view of MVC

Here is my view, I want to retrieve the item whose id is "SRInfo" in my Combo, when "No is selected", and then set SRInfo visible:

Ext.define('FSSP.view.reqform.newReq', {
extend: 'Ext.form.Panel',
alias: 'widget.newReqForm',

...

items: [
    {
    xtype: 'fieldcontainer',
    fieldLabel: 'Basic Information',
    labelStyle: 'font-weight:bold;padding:0',
    layout: 'anchor',
    defaults: {
        layout: '100%'
    },

    fieldDefaults: {
        labelAlign: 'top'
    },


    items: [{

        xtype: 'fieldcontainer',
        labelStyle: 'font-weight:bold;padding:0',
        layout: 'hbox', 
        defaultType: 'textfield',
        fieldDefaults: {
            labelAlign: 'top'
        },

        items:[{
            flex: 1,
            xtype: 'combo',
            fieldLabel: '<font color="red">*</font> SR Open?',
            allowBlank: false,

            store: new Ext.data.SimpleStore({
                data: [['Y', 'Yes'], ['N', 'No']],
                id: 0,
                fields: ['value', 'text']
            }),

            listeners:  {
                  scope: this, 
          'select': function(combo,records){
        var i = records[0].get('text');
        if( i == 'No'){

el = Ext.getElement("SRInfo"); // it d开发者_开发百科oesn't work, and I tried a couple of other ways, Ext.Element.select, Ext.element.query

                    el.setVisible(true);

                    }
         }                          
            }
...

 {
    xtype: 'fieldcontainer',
    labelStyle: 'font-weight:bold;padding:0',
    **id: "SRInfo",**
    layout: 'hbox',
    defaultType: 'textfield',
    hidden: true,

    fieldDefaults: {
        labelAlign: 'top'
    },

    items: [
    {
        flex: 2,
        name: 'number',
        fieldLabel: 'SR Reason',
        allowBlank: false,
        margins: '0 0 0 5'
    },
    {
        flex: 2,
        name: 'region',
        fieldLabel: 'SR Comments',
        allowBlank: false,
        margins: '0 0 0 5'
    }]
}]
    },

Ext.define('FSSP.view.reqform.newReq', {
extend: 'Ext.form.Panel',
alias: 'widget.newReqForm',
...
initComponent: function() {

this.hiddenItem = Ext.create(...);

Ext.appy(this,{
items:[
{
...
listener: function(){ this.hiddentItem.show()};
...
},
{
...
},

 this,hiddenItem
]

})