UISearchController's searchbar is not responding

Question

I am not able to get responding events on tapping UISearchController's search bar in iOS 8.

I am displaying custom view with dim background like alert view appearance, on pressing button in a view, where custom view has UISearchController's search bar as sub view. Programmatically added searchController. When I try to touch search bar, it is not responding in iOS 8 whereas I have added search bar with UISearchDisplayController for iOS 7, it is working fine.

I have viewController A with navigation bar. In viewController A, I have a button. On pressing button, I am trying to show view as custom view with dim background like alert view appearance. So I have added following line in button method.

class_name *view = [[class_name alloc] initWithNibName:@"xib_name" bundle:nil];
[self.navigationController.view addSubview:view];

Xib file of class_name has dim background with subviews like searchController's search bar.

Instead of

[self.navigationController.view addSubview:view];

added

[self presentViewController:view animated:YES completion:nil];

UISearchController's search bar is working now but i am not able to get transparent background view, instead black background appears.

I need to display previous views content and on top that current views content like alert view.

Please guide me in objective-C.