[removed] and scrolling on iOS 5

Question

iOS 5 has brought a number of nice things to JavaScript/Web Apps. One of them is improved scrolling. If you add

-webkit-overflow-scroll:touch;

Answer 1

The only issue with Brian Nickel's answer is that (as user1012566 mentioned) stopPropagation doesn't prevent bubbling when you hit your scrollable's boundaries. You can prevent this with the following:

elem.addEventListener('touchstart', function(event){
    this.allowUp = (this.scrollTop > 0);
    this.allowDown = (this.scrollTop < this.scrollHeight - this.clientHeight);
    this.prevTop = null; 
    this.prevBot = null;
    this.lastY = event.pageY;
});

elem.addEventListener('touchmove', function(event){
    var up = (event.pageY > this.lastY), 
        down = !up;

    this.lastY = event.pageY;

    if ((up && this.allowUp) || (down && this.allowDown)) 
        event.stopPropagation();
    else 
        event.preventDefault();
});