How to detect when a UIScrollView has finished scrolling

The 320 implementations are so much better - here is a patch to get consistent start/ends of the scroll.

-(void)scrollViewDidScroll:(UIScrollView *)sender {   [NSObject cancelPreviousPerformRequestsWithTarget:self];    //ensure that the end of scroll is fired.    [self performSelector:@selector(scrollViewDidEndScrollingAnimation:) withObject:sender afterDelay:0.3]; ...}-(void)scrollViewDidEndScrollingAnimation:(UIScrollView *)scrollView{    [NSObject cancelPreviousPerformRequestsWithTarget:self];...}

- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView {    [self stoppedScrolling];}- (void)scrollViewDidEndDragging:(UIScrollView *)scrollView willDecelerate:(BOOL)decelerate {    if (!decelerate) {        [self stoppedScrolling];    }}- (void)stoppedScrolling {    // ...}

For all scrolls related to dragging interactions, this will be sufficient:

- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView {    _isScrolling = NO;}- (void)scrollViewDidEndDragging:(UIScrollView *)scrollView willDecelerate:(BOOL)decelerate {    if (!decelerate) {        _isScrolling = NO;    }}

Now, if your scroll is due to a programmatic setContentOffset/scrollRectVisible (with animated = YES or you obviously know when scroll is ended):

 - (void)scrollViewDidEndScrollingAnimation {     _isScrolling = NO;}

If your scroll is due to something else (like keyboard opening or keyboard closing), it seems like you'll have to detect the event with a hack because scrollViewDidEndScrollingAnimation is not useful either.

The case of a PAGINATED scroll view:

Because, I guess, Apple apply an acceleration curve, scrollViewDidEndDecelerating get called for every drag so there's no need to use scrollViewDidEndDragging in this case.