ios - 未调用IBOutlet类init，成员为零

I am trying to add search capabilities to the map based project I am working on in swift on XCode 6. I have added SearchDisplayController to my main view controller, which contains the map. I created a class called MapSearchDisplayController, which implements necessary methods. I also changed Custom Class property of the SearchDisplayController to MapSearchDisplayController in the storyboard.I am trying to add search capabilities to the m