content offset changes unexpectedly while zooming programmatically in uiscrollview

Question

I am having 1.0 - 4.0 zoomscale when I zoom after scale 3.7, content offset changes unexpectedly to last visible rect (lower - right).

How to fix this?

Answer 1

Shift your origin of scroll view according to the size of view after zooming.

 - (void)scrollViewDidEndZooming:(UIScrollView *)scrollView withView:(UIView *)view atScale:(float)scale {

     CGFloat vPadding;
     CGFloat hPadding;
     if ((480-view.frame.size.height)/2 > 0) {
          vPadding=(480-view.frame.size.height)/2;
     }
     else{
          vPadding=0;
     }
     if ((320-view.frame.size.width)/2 > 0) {
          hPadding=(320-view.frame.size.width)/2;
     }
     else{
          hPadding=0;
     }
     yourView.frame = CGRectMake(hPadding, vPadding, view.frame.size.width, view.frame.size.height);

}

OR change scroll view centre accordingly.