Adding header view to WKWebView ScrollView

In webView Delegate method

- (void)webViewDidFinishLoad:(UIWebView *)webView

add the following codebase,

mainWebViewObj.scrollView.contentInset = UIEdgeInsetsMake(headerView.frame.size.height,0.0,headerView.frame.size.height,0.0);
mainWebViewObj.scrollView.backgroundColor = [UIColor whiteColor];

if(![headerView superview])
{
    [webView.scrollView addSubview:headerView];
    [webView.scrollView bringSubviewToFront:headerView];
}
[mainWebViewObj.scrollView setContentOffset:
 CGPointMake(0, -mainWebViewObj.scrollView.contentInset.top) animated:NO];

this worked perfect for me. Hope it solves your problem.