How to implement auto-complete for address using Apple Map Kit

Update – I’ve created a simple example project here using Swift 3 as the original answer was written in Swift 2.

In iOS 9.3 a new class called MKLocalSearchCompleter was introduced, this allows the creation of an autocomplete solution, you simply pass in the queryFragment as below:

var searchCompleter = MKLocalSearchCompleter()
searchCompleter.delegate = self
var searchResults = [MKLocalSearchCompletion]()

searchCompleter.queryFragment = searchField.text!

Then handle the results of the query using the MKLocalSearchCompleterDelegate:

extension SearchViewController: MKLocalSearchCompleterDelegate {

    func completerDidUpdateResults(completer: MKLocalSearchCompleter) {
        searchResults = completer.results
        searchResultsTableView.reloadData()
    } 

    func completer(completer: MKLocalSearchCompleter, didFailWithError error: NSError) {
        // handle error
    }
}

And display the address results in an appropriate format:

func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
    let searchResult = searchResults[indexPath.row]
    let cell = UITableViewCell(style: .subtitle, reuseIdentifier: nil)
    cell.textLabel?.text = searchResult.title
    cell.detailTextLabel?.text = searchResult.subtitle
    return cell
}

You can then use a MKLocalCompletion object to instantiate a MKLocalSearch.Request, thus gaining access to the MKPlacemark and all other useful data:

let searchRequest = MKLocalSearch.Request(completion: completion!)
let search = MKLocalSearch(request: searchRequest)
search.startWithCompletionHandler { (response, error) in
    if error == nil {
        let coordinate = response?.mapItems[0].placemark.coordinate
    }
}