title: Creating UIViewController Category (Obj-C) similar to Extension Swift
body: <p>I'm trying to extend standard <code>UIViewController</code> with some custom methods.</p>
  
  <pre><code>#import &lt;UIKit/UIKit.h&gt;
  
  @interface UIViewController (UIViewControllerExtension)
  - (void) showNoHandlerAlertWithTitle:(NSString *)title andMessage:     (NSString*)message;
  - (void) showAlertWithTitle:(NSString *)title andMessage:(NSString*)message  buttonTitles:(NSArray&lt;NSString *&gt;*)titles andHandler:(void (^)(UIAlertAction * action))handler;
  @end
  </code></pre>
  
  <p>How can I use extended <code>UIViewController</code> now? I need to inherit my custom view controllers from extended <code>UIViewController</code>.</p>