show FPS - Sencha Touch 2.2

gistfile1.js

Ext.Viewport.add([
    {
        id    : 'currentFPS',
        xtype : 'component',
        bottom: 0,
        right : 0,
        width : 50,
        height: 50,
        style : 'background-color: red; color: white;'
    },
    {
        id    : 'averageFPS',
        xtype : 'component',
        bottom: 0,
        left  : 0,
        width : 50,
        height: 50,
        style : 'background-color: green; color: white;'
    }
]);

var fpsIndicator = Ext.getCmp('currentFPS'),
    fpsAverage = Ext.getCmp('averageFPS'),
    fpsCount = 0,
    fpsSum = 0;

Ext.AnimationQueue.onFpsChanged = function(fps) {
    fpsCount++;
    fpsSum += fps;
    fpsIndicator.setHtml(Math.round(fps));
    fpsAverage.setHtml(Math.round(fpsSum / fpsCount));
};