title: nib must contain exactly one top level object which must be a UITableViewHeaderFooterView instance
body: <p>I am running into a weird issue when creating a customHeader for my tableView. the error that I am receiving is the following:</p>
  
  <p>nib must contain exactly one top level object which must be a UITableViewHeaderFooterView instance</p>
  
  <p>I ran through my code and xib file as well as examples but I couldnt find anything wrong any ideas I am missing?</p>
  
  <p>The header Xib was created with a regular view and then a sub view with a label, the class was created with the following:</p>
  
  <p>CustomTableHeader Class:</p>
  
  <pre><code>class CustomTableHeader: UITableViewHeaderFooterView {
      static var CustomTableHeaderIdentifier = "CustomTableHeader"
      @IBOutlet weak var titleLabel: UILabel!
  
      override awakeFromNib(){
           super.awakeFromNib()
           self.titleLabel.text = "Header"
      }
  
      override func prepareForReuse() {
          super.prepareForReuse()
      }
  }
  </code></pre>
  
  <p>ViewController Class:</p>
  
  <pre><code>class ViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {
      @IBOutlet weak var tableView: UITableView!
  
      override func viewDidLoad() {
          super.viewDidLoad()
  
          self.tableView.register(UINib.init(nibName: CustomTableHeader.CustomTableHeaderIdentifier, bundle: nil), forHeaderFooterViewReuseIdentifier: CustomTableHeader.CustomTableHeaderIdentifier)
      }
  
  
      //Other Methods
       func tableView(_ tableView: UITableView, viewForHeaderInSection section: Int) -&gt; UIView? {
           if let header = tableView.dequeueReusableHeaderFooterView(withIdentifier: CustomTableHeader.CustomTableHeaderIdentifier) as? CustomTableHeader {
              header.titleLabel.text = "Section 1"
              return header
       }
  }
  </code></pre>