I hope you have done something like this :
Code:
Ext.define('App.controller.controllerName', {
    
    extend : 'Ext.app.Controller',
    
    stores : [ '' ],
    
    models : [ '' ],
    
    views : [ '' ],
    
    dataRec  :[]
You can access the variable as :
Code:
appReference.getController('controllerName').dataRec
where appReference is defined in app.js as:
Code:
launch: function () {
        appReference = this;