grid example

HTML

<script src="http://cdn.sencha.io/ext-4.2.0-gpl/ext-all-dev.js"></script>
<link rel="stylesheet" href="http://cdn.sencha.io/ext-4.2.0-gpl/resources/css/ext-all.css">
<script src="http://cdn.sencha.io/ext-4.2.0-gpl/examples/ux/statusbar/StatusBar.js"></script>
<script src="http://cdn.sencha.io/ext-4.2.0-gpl/examples/ux/LiveSearchGridPanel.js"></script>

JavaScript

Ext.define('MyApp.overrides.Ext',{
    override: 'Ext',

    emptyStore: Ext.getStore('ext-empty-store'),

    getStore: function(name, create, opts) {
        var s = Ext.data.StoreManager.lookup(name);
        if(Ext.isEmpty(s)){
            if(Ext.isObject(create)&& !Ext.isEmpty(create.store)){
                var cfg = Ext.clone(create);
                delete cfg.store;
                s = Ext.create(create.store, Ext.apply({
                    storeId: name
                }, cfg));
            }
            if(create === true && Ext.getApplication.name) {
                s = Ext.create(Ext.getApplication.name + '.store.' + name, Ext.apply({
                    storeId: name
                }, opts));
            }
        }
        return s;
    }
});

var store = Ext.getStore("personStore", true);
console.log(store);