title: NSDictionary Predicate filter on child objects
body: <p>I'm trying to filter a response from Facebook's API, the JSON looks like this:</p>
  
  <pre><code>{ 
   "Data": [
    {  
      "first_name" : "Joe",
      "last_name" : "bloggs",
      "uuid" : "123"
    },
    {  
      "first_name" : "johnny",
      "last_name" : "appleseed",
      "uuid" : "321"
    }
   ]
  }
  </code></pre>
  
  <p>I load this into a NSDictionary, accessing it like <code>[[friendDictionary objectForKey:@"data"] allObjects]</code></p>
  
  <p>I'm now trying to filter based on the <code>first_name</code> and <code>last_name</code> based on when someone inputs a name into a textfield. Here's what I have but its failing horribly:</p>
  
  <pre><code>  NSPredicate *filter = [NSPredicate predicateWithFormat:[NSString stringWithFormat:@"ANY.first_name beginswith[c] %@ OR ANY.last_name beginswith[c] %@", friendField.text, friendField.text]];
    NSLog(@"%@", [[[friendDictionary objectForKey:@"data"] allObjects] filteredArrayUsingPredicate:filter]);
  </code></pre>
  
  <p>Any help is greatly appreciated, thanks guys</p>