force-stop momentum scrolling on iphone/ipad in javascript

Question

Is it possible to force-stop momentum scrolling on iphone/ipad in javascript?

Extra: pretty sure this is pie in the sky, but for bonuspoints (honor and kudos), after dom-manipulation and a scrollTo applied, resume scroll with the same momentum before the forced stop. How to?

Answer 1

This is actually very possible when using fastclick.js. The lib removes the 300ms click delay on mobile devices and enables event capturing during inertia/momentum scrolling.

After including fastclick and attaching it to the body element, my code to stop scrolling and go to the top looks like this:

scrollElement.style.overflow = 'hidden';
scrollElement.scrollTop = 0;
setTimeout(function() {
  scrollElement.style.overflow = '';
}, 10);

The trick is to set overflow: hidden, which stops the inertia/momentum scrolling. Please see my fiddle for a full implementation of stop scrolling during inertia/momentum.

Answer 2

Here is my code using jQuery animation (running as onclick event)

var obj=$('html, body'); // your element

if(!obj.is(':animated')) {

    obj.css('overflow', 'hidden').animate({ scrollTop: 0 }, function(){ obj.css('overflow', ''); });

}

Tested on iPhone 6