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copied!<p>I implemented something like this:</p> <pre><code>@interface ProxyScrollView : NSObject <UIScrollViewDelegate> { UIScrollView* _view; id<UIScrollViewDelegate> origDelegate; id<UIScrollViewDelegate> newDelegate; } + (ProxyScrollView*) proxyScrollViewWithScrollView: (UIScrollView*) scrollView; @end @implementation ProxyScrollView - (id) initWithScrollView: (UIScrollView*) scrollView { if(self != nil) { _view = scrollView; origDelegate = _view.delegate; [_view setDelegate:self]; newDelegate = nil; [_view retain]; return self; } return nil; } -(void)dealloc { _view.delegate = origDelegate; [_view release]; _view = nil; origDelegate = nil; newDelegate = nil; } + (ProxyScrollView*) proxyScrollViewWithScrollView: (UIScrollView*) scrollView { ProxyScrollView* retVal = [[[ProxyScrollView alloc] initWithScrollView:scrollView] autorelease]; return retVal; } - (BOOL)isKindOfClass:(Class)aClass { return [_view isKindOfClass:aClass]; } - (BOOL)isMemberOfClass:(Class)aClass { return [_view isMemberOfClass:aClass]; } - (BOOL)respondsToSelector:(SEL)aSelector { if ( [super respondsToSelector:aSelector] ) return YES; else { /* Here, test whether the aSelector message can * * be forwarded to another object and whether that * * object can respond to it. Return YES if it can. */ if([_view respondsToSelector:aSelector]) return YES; } return NO; } - (NSMethodSignature *)methodSignatureForSelector:(SEL)sel { NSMethodSignature *sig = [super methodSignatureForSelector:sel]; if(!sig) { sig = [_view methodSignatureForSelector:sel]; } return sig; } - (void)forwardInvocation:(NSInvocation *)inv { NSLog(@"inv.selector: %@", NSStringFromSelector(inv.selector)); if([_view respondsToSelector: inv.selector]) { [inv invokeWithTarget: _view]; } } - (void)setDelegate:(id<UIScrollViewDelegate>)delegate { newDelegate = delegate; } - (void)scrollViewDidScroll:(UIScrollView *)scrollView { if([origDelegate respondsToSelector:_cmd]) [origDelegate performSelector:_cmd withObject:scrollView]; if([newDelegate respondsToSelector:_cmd]) [newDelegate performSelector:_cmd withObject:scrollView]; } - (void)scrollViewDidZoom:(UIScrollView *)scrollView { if([origDelegate respondsToSelector:_cmd]) [origDelegate performSelector:_cmd withObject:scrollView]; if([newDelegate respondsToSelector:_cmd]) [newDelegate performSelector:_cmd withObject:scrollView]; } -(void)scrollViewWillBeginDragging:(UIScrollView *)scrollView { if([origDelegate respondsToSelector:_cmd]) [origDelegate performSelector:_cmd withObject:scrollView]; if([newDelegate respondsToSelector:_cmd]) [newDelegate performSelector:_cmd withObject:scrollView]; } - (void)scrollViewWillEndDragging:(UIScrollView *)scrollView withVelocity:(CGPoint)velocity targetContentOffset:(inout CGPoint *)targetContentOffset { if([origDelegate respondsToSelector:_cmd]) [origDelegate scrollViewWillEndDragging:scrollView withVelocity:velocity targetContentOffset:targetContentOffset]; if([newDelegate respondsToSelector:_cmd]) [newDelegate scrollViewWillEndDragging:scrollView withVelocity:velocity targetContentOffset:targetContentOffset]; } - (void)scrollViewDidEndDragging:(UIScrollView *)scrollView willDecelerate:(BOOL)decelerate { if([origDelegate respondsToSelector:_cmd]) [origDelegate scrollViewDidEndDragging:scrollView willDecelerate:decelerate]; if([newDelegate respondsToSelector:_cmd]) [newDelegate scrollViewDidEndDragging:scrollView willDecelerate:decelerate]; } - (void)scrollViewWillBeginDecelerating:(UIScrollView *)scrollView { if([origDelegate respondsToSelector:_cmd]) [origDelegate performSelector:_cmd withObject:scrollView]; if([newDelegate respondsToSelector:_cmd]) [newDelegate performSelector:_cmd withObject:scrollView]; } - (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView { if([origDelegate respondsToSelector:_cmd]) [origDelegate performSelector:_cmd withObject:scrollView]; if([newDelegate respondsToSelector:_cmd]) [newDelegate performSelector:_cmd withObject:scrollView]; } - (void)scrollViewDidEndScrollingAnimation:(UIScrollView *)scrollView { if([origDelegate respondsToSelector:_cmd]) [origDelegate performSelector:_cmd withObject:scrollView]; if([newDelegate respondsToSelector:_cmd]) [newDelegate performSelector:_cmd withObject:scrollView]; } - (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView { if([newDelegate respondsToSelector:_cmd]) [newDelegate performSelector:_cmd withObject:scrollView]; if([origDelegate respondsToSelector:_cmd]) return [origDelegate performSelector:_cmd withObject:scrollView]; return nil; } - (void)scrollViewWillBeginZooming:(UIScrollView *)scrollView withView:(UIView *)view __OSX_AVAILABLE_STARTING(__MAC_NA,__IPHONE_3_2) { if([origDelegate respondsToSelector:_cmd]) [origDelegate performSelector:_cmd withObject:scrollView withObject:view]; if([newDelegate respondsToSelector:_cmd]) [newDelegate performSelector:_cmd withObject:scrollView withObject:view]; } - (void)scrollViewDidEndZooming:(UIScrollView *)scrollView withView:(UIView *)view atScale:(float)scale { if([origDelegate respondsToSelector:_cmd]) [origDelegate scrollViewDidEndZooming:scrollView withView:view atScale:scale]; if([newDelegate respondsToSelector:_cmd]) [newDelegate scrollViewDidEndZooming:scrollView withView:view atScale:scale]; } - (BOOL)scrollViewShouldScrollToTop:(UIScrollView *)scrollView { if([newDelegate respondsToSelector:_cmd]) [newDelegate scrollViewShouldScrollToTop:scrollView]; if([origDelegate respondsToSelector:_cmd]) return [origDelegate scrollViewShouldScrollToTop:scrollView]; return false; } - (void)scrollViewDidScrollToTop:(UIScrollView *)scrollView { if([origDelegate respondsToSelector:_cmd]) [origDelegate performSelector:_cmd withObject:scrollView]; if([newDelegate respondsToSelector:_cmd]) [newDelegate performSelector:_cmd withObject:scrollView]; } @end </code></pre> <p>Then I return:</p> <pre><code>for (id subview in webView.subviews) if ([[subview class] isSubclassOfClass: [UIScrollView class]]) return [ProxyScrollView proxyScrollViewWithScrollView: (UIScrollView*) subview]; </code></pre> <p>In my case, I keep a singleton ProxyScrollView for my webView and return that.</p>

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