Answered MODExt - Get total number of records of grid after load

,{
xtype: 'tbtext'
,id: 'recNum'
,text: 'Loading...'
}

,listeners: {
    // This listener is added to the grid itself so "this" represents "grid" and the function will run when the grid is rendered.
    render: function() {
        // Check for any existing records (this is not a good tactic if it's possible your grid won't have any records)
        if (this.store.getCount() == 0) {
            console.log('store not loaded yet');
            // The load listener is applied to this grid's store.
            this.store.on('load', function() {
                console.log('load after render');
                // We can now get the data as it's been loaded and count the number of records. We use the update function to replace the "Loading..." text.
                Ext.getCmp('recNum').update(this.store.getCount());
            }, this, {
                single: true
            });
        } else {
            console.log('store already loaded');
        }
    }
}