title: How do I change the navigationItem.title to the color white in Swift 4?
body: <p>How do I change the navigationItem.title to the color white in Swift 4?      </p>
  
  <pre><code>let uid = Auth.auth().currentUser?.uid
  Database.database().reference().child("users").child(uid!).observeSingleEvent(of: .value, with: {(snapshot) in          
      if let dictionary = snapshot.value as? [String: AnyObject] {
          self.navigationItem.title = dictionary["name"] as? String
          self.navigationController?.navigationBar.prefersLargeTitles = true
      }
  },withCancel: nil)
  </code></pre>