Cancel UIScrollView bounce after dragging

Question

I have a horizontal UIScrollView. I want to do a variation of the \"pull-to-reset\" animation, where I pull all the way past the right edge of the scroll view\'s content siz

Answer 1

I accomplished cancelling the bounce back animation of a UIScrollView.

I wanted to leave the default behaviour during a rapid scroll to the top when it bounces. However if scrollview is already at the top and then the user pulls it down and releases (analogous to pull to refresh) I wanted to take the control over the bounce back and do something custom.

In scrollview delegate I track the initial position:

- (void)scrollViewWillBeginDragging:(UIScrollView *)scrollView
{
    if (scrollView.contentOffset.y < 0.1)
    {
        isPullingTop = YES;
    }
}

In scrollview delegate detect if the flag is set and scrollview is dragged enough

- (void)scrollViewDidEndDragging:(UIScrollView *)scrollView willDecelerate:(BOOL)decelerate
{
    if (isPullingTop && scrollView.contentOffset.y < -30) {

        overrideBounce = YES;
    }
    isPullingTop = NO;
}

I subclass scrollview and override the setContentOffset:

-(void)setContentOffset:(CGPoint)contentOffset
{
    if (!overrideBounce)
    {
        [super setContentOffset:contentOffset];
    }
    else
    {
        //customs stuff goes here , for example an animation
        overrideBounce = NO;
    }
}

Answer 2

try this

- (void)scrollViewDidEndDragging:(UIScrollView *)scrollView willDecelerate:(BOOL)decelerate {
  //check if it exceeds a certain critical value
  if (scrollView.contentOffset.x - (scrollView.contentSize.width - IMAGE_WIDTH) > 80) {
    [scrollView setContentOffset:CGPointMake(0, 0) animated:YES];
  }
}