title: Objective-C callback handler
body: <p>I have a callback method that I got to work, but I want to know how to pass values to it.</p>
  
  <p>What I have is this:</p>
  
  <pre><code>@interface DataAccessor : NSObject
  {
      void (^_completionHandler)(Account *someParameter);
  
  }
  
  
  - (void) signInAccount:(void(^)(Account *))handler;
  </code></pre>
  
  <p>The code above works, but I want to pass values to the method.  How would this look?  Something like:</p>
  
  <pre><code>- (void) signInAccount:(void(^)(Account *))handler user:(NSString *) userName pass:(NSString *) passWord;
  </code></pre>
  
  <p>?</p>