Forward scrollToTop event to webview in PhoneGap iOS

AppDelegate.h

// add UIScrollViewDelegate
@interface AppDelegate : PhoneGapDelegate <UIScrollViewDelegate>

AppDelegate.m

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
  //.. phonegap's code //

  BOOL result = [super application:application didFinishLaunchingWithOptions:launchOptions];

  // disable scrolltotop in webview as we add our dummy scrollview to catch this event
  // only one scrollview can catch the event
  if ([[self.webView subviews] count] > 0) {
    UIScrollView *scrollView = (UIScrollView *)[[self.webView subviews] objectAtIndex:0];
    if ([scrollView respondsToSelector:@selector(setScrollsToTop:)]) {
      [scrollView setScrollsToTop:NO];
    }
  }

  // dummy scrollview to catch scrolltotop event
  UIScrollView *dummyScrollView = [[UIScrollView alloc] init];
  dummyScrollView.delegate = self;
  [self.viewController.view addSubview:dummyScrollView];
  [self.viewController.view sendSubviewToBack:dummyScrollView];
  dummyScrollView.contentSize = CGSizeMake(self.viewController.view.frame.size.width,
                                           self.viewController.view.frame.size.height+200);
  dummyScrollView.contentOffset = CGPointMake(0, 1); 
  [dummyScrollView release];

  return result;
}

// forward event to webview as scrollToTop event on document using jQuery/zepto.js
- (BOOL)scrollViewShouldScrollToTop:(UIScrollView *)scrollView
{
  NSLog(@"scrollViewShouldScrollToTop");
  NSString *jsString = @"if (typeof $ === 'function' && typeof $(document).trigger === 'function') $(document).trigger('scrollToTop');";
  [self.webView stringByEvaluatingJavaScriptFromString:jsString];
  return NO;
}

In your webpage then just listen to scrollToTop on document

$(document).bind('scrollToTop', function(){ /* your stuff.. */ });