Iphone – Deactivate UIScrollView decelerating

cocoa-touchiphoneiphone-sdk-3.0uiscrollview

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.

Best Answer

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 UIScrollView object if you have not already done so.

In your delegate's .m implementation file, add the following lines of code:

-(void)scrollViewWillBeginDecelerating:(UIScrollView *)scrollView{  
    [scrollView setContentOffset:scrollView.contentOffset animated:YES];   
}

Voila! No more auto-scroll.

Related Solutions

Ios – Stop UIWebView from “bouncing” vertically

for (id subview in webView.subviews)
  if ([[subview class] isSubclassOfClass: [UIScrollView class]])
    ((UIScrollView *)subview).bounces = NO;

...seems to work fine.

It'll be accepted to App Store as well.

Update: in iOS 5.x+ there's an easier way - UIWebView has scrollView property, so your code can look like this:

webView.scrollView.bounces = NO;

Same goes for WKWebView.

Ios – 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];
...
}

Best Answer

Related Solutions

Ios – Stop UIWebView from “bouncing” vertically

Ios – How to detect when a UIScrollView has finished scrolling

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