Is there a way to deactivate the decelerating of a UIScrollView?
I want to allow the user to scroll the canvas, but I don't want that the canvas continues scrolling after the user lifted the finger.
5 Answers
This can be done by utilizing the UIScrollView delegate method scrollViewWillBeginDecelerating to automatically set the content offset to the current screen position.
To implement:
- Assign a delegate to your
UIScrollViewobject if you have not already done so. In your delegate's
.mimplementation file, add the following lines of code:-(void)scrollViewWillBeginDecelerating:(UIScrollView *)scrollView{ [scrollView setContentOffset:scrollView.contentOffset animated:YES]; }
Voila! No more auto-scroll.
You can just turn up the deceleration rate very high. With an infinite rate, it would stop immediately. Try setting the rate to these constants:
scrollView.decelerationRate = UIScrollViewDecelerationRateNormal;
and
scrollView.decelerationRate = UIScrollViewDecelerationRateFast;
If fast still isn't fast enough for you, UIScrollViewDecelerationRateFast is just typedef'ed as a float, so you can just multiply it by a factor of 10 or so to speed it up even more.
Previous Swift version:↓
scrollView.decelerationRate = UIScrollView.DecelerationRate.fast
Current Swift 4.2 version code:↓
scrollView.decelerationRate = UIScrollViewDecelerationRateFast
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