Can't interact with UIView added to Window

I'm adding a view to the window with this objective-c code:

  // Main Storyboard
  UIStoryboard *mainStoryBoard = [UIStoryboard  storyboardWithName:@"Main" bundle: nil];

  // View controller with the view to add
  UIViewController *vc = [mainStoryBoard instantiateViewControllerWithIdentifier:@"SomeViewController"];

  // Find the topmost window
  UIWindow *topWindow = [[[UIApplication sharedApplication].windows sortedArrayUsingComparator:^NSComparisonResult(UIWindow *win1, UIWindow *win2) {
   return win1.windowLevel < win2.windowLevel || !win1.isOpaque;
  }] lastObject];

  // Add the view to the window
  [topWindow addSubview:vc.view];

This works fine and so does this Swift method I use in SomeViewController to leave the view:

// Get topmost window (Should be UIWindow)
let topWindow = UIApplication.shared.windows.sorted {
  (win1, win2) in
  return win1.windowLevel < win2.windowLevel || !win1.isOpaque
}.last

// Force view to prepare to disappear
self.viewWillDisappear(true)

// Send the view to the back
topWindow?.sendSubviewToBack(view)

This is the structure of my views after the objective-c code runs. The selected view is the one that got added:

The issue is none of the buttons in the new view work so I can't trigger the above close method. I've tried both buttons added with the storyboard and programmatically added buttons. Visually the buttons react when tapped but they won't trigger anything.

I ended up resolving the issue by completely swapping out the root view controller rather than simply adding it's view as a subview. The problem was as @DonMag pointed out that I was adding the subview without it's view controller. I found this question about swapping the root view controller and used that as a basis for my changes. If someone wants to provide a complete solution that doesn't require swapping the root view controller I'll accept that instead.