iPhone X how to handle View Controller inputAccessoryView?

Question

I have a messaging app that has the typical UI design of a text field at the bottom of a full screen table view. I am setting that text field to be the view controller\'s

Answer 1

From code (Swift 4). Idea - monitoring layoutMarginsDidChange event and adjusting intrinsicContentSize.

public final class AutoSuggestionView: UIView {

   private lazy var tableView = UITableView(frame: CGRect(), style: .plain)
   private var bottomConstraint: NSLayoutConstraint?
   var streetSuggestions = [String]() {
      didSet {
         if streetSuggestions != oldValue {
            updateUI()
         }
      }
   }
   var handleSelected: ((String) -> Void)?

   public override func initializeView() {
      addSubview(tableView)
      setupUI()
      setupLayout()
      // ...
      updateUI()
   }

   public override var intrinsicContentSize: CGSize {
      let size = super.intrinsicContentSize
      let numRowsToShow = 3
      let suggestionsHeight = tableView.rowHeight * CGFloat(min(numRowsToShow, tableView.numberOfRows(inSection: 0)))
      //! Explicitly used constraint instead of layoutMargins
      return CGSize(width: size.width,
                    height: suggestionsHeight + (bottomConstraint?.constant ?? 0))
   }

   public override func layoutMarginsDidChange() {
      super.layoutMarginsDidChange()
      bottomConstraint?.constant = layoutMargins.bottom
      invalidateIntrinsicContentSize()
   }
}

extension AutoSuggestionView {

   private func updateUI() {
      backgroundColor = streetSuggestions.isEmpty ? .clear : .white
      invalidateIntrinsicContentSize()
      tableView.reloadData()
   }

   private func setupLayout() {

      let constraint0 = trailingAnchor.constraint(equalTo: tableView.trailingAnchor)
      let constraint1 = tableView.leadingAnchor.constraint(equalTo: leadingAnchor)
      let constraint2 = tableView.topAnchor.constraint(equalTo: topAnchor)
      //! Used bottomAnchor instead of layoutMarginGuide.bottomAnchor
      let constraint3 = bottomAnchor.constraint(equalTo: tableView.bottomAnchor)
      bottomConstraint = constraint3
      NSLayoutConstraint.activate([constraint0, constraint1, constraint2, constraint3])
   }
}

Usage:

let autoSuggestionView = AutoSuggestionView()
// ...
textField.inputAccessoryView = autoSuggestionView

Result: