Touchscreen swipe events for image rotator

gistfile1.js

if (Modernizr.touch) {

    var hero = $('#hero');

    var touchCancel = function()
    {
        hero[0].removeEventListener('touchmove', touchMove, false);
        hero[0].data('touch', false);
    };

    var touchMove = function(e)
    {
        if (hero.data('_touch')) {
            var dx = hero.data('_touchX') - e.touches[0].pageX;
            var dy = hero.data('_touchY') - e.touches[0].pageY;
            if (Math.abs(dx) >= 20) {
                touchCancel();
                if (dx < 0) {
                    hero.find('.nav-prev').trigger('click');
                } else {
                    hero.find('.nav-next').trigger('click');
                }
            }
        }
    };

    hero[0].addEventListener('touchstart', function(e)
    {
        if (e.touches.length === 1) {
            hero.data('_touchX', e.touches[0].pageX);
            hero.data('_touchY', e.touches[0].pageY);
            hero.data('_touch', true);
            hero[0].addEventListener('touchmove', touchMove, false);
        }
    });

}