Foo : anotherClass

<UIWebViewDelegate>

Foo : UIViewController {}
- (void)customWebViewDidFinishLoad:(UIWebView *)webView;

- (void)webViewDidFinishLoad:(UIWebView *)theWebView {
    [self customWebViewDidFinishLoad:self.webView];
}

// Override this method in Bar.m
- (void)customWebViewDidFinishLoad:(UIWebView *)webView {
    // Default behaviour
}

Bar : Foo

- (void)customWebViewDidFinishLoad:(UIWebView *)webView {
  [super customWebViewDidFinishLoad:webView];
  //Extend the behaviour here
}