如何使用 Apple Map Kit 实现地址自动完成

Question

我想自动完成用户的地址，就像 google api 在此链接中提供的一样：

https://developers.google.com/maps/documentation/javascript/places-autocomplete?hl=en

如何使用苹果地图套件实现相同的功能？

我曾尝试使用 Geo Coder，例如：

@IBAction func SubmitGeoCode(sender: AnyObject) {

    let address = "1 Mart"
    let coder = CLGeocoder()

    coder.geocodeAddressString(address) { (placemarks, error) -> Void in

        for placemark in placemarks! {

            let lines = placemark.addressDictionary?["FormattedAddressLines"] as? [String]

            for addressline in lines! {
                print(addressline)
            }
        }
    }
}

但是结果非常令人失望。

任何可用于实现此类功能的 Apple API，还是我应该使用 google api？

谢谢

Answer 1

更新 - 我使用 Swift 3 创建了一个简单的示例项目 here，因为原始答案是用 Swift 2 编写的。

在 iOS 9.3 中引入了一个名为 MKLocalSearchCompleter 的新类，这允许创建自动完成解决方案，您只需传入如下 queryFragment：

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

searchCompleter.queryFragment = searchField.text!

然后使用MKLocalSearchCompleterDelegate处理查询结果：

extension SearchViewController: MKLocalSearchCompleterDelegate {

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

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

并以适当的格式显示地址结果：

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
}

然后您可以使用MKLocalCompletion 对象来实例化MKLocalSearch.Request，从而获得对MKPlacemark 和所有其他有用数据的访问权限：

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
    }
}

Answer 2

Swift 5 + Combine +（可选）SwiftUI 解决方案

在其他解决方案上似乎有许多 cmets 想要一个与最新版本的 Swift 兼容的版本。另外，似乎（就像我一样）人们也需要 SwiftUI 解决方案。

这建立在之前的建议之上，但使用 Combine 来监控输入、消除抖动，然后通过 Publisher 提供结果。

MapSearchObservableObject 很容易在 SwiftUI 中使用（提供示例），但也可以在非 SwiftUI 情况下使用。

MapSearch ObservableObject

import SwiftUI
import Combine
import MapKit

class MapSearch : NSObject, ObservableObject {
    @Published var locationResults : [MKLocalSearchCompletion] = []
    @Published var searchTerm = ""
    
    private var cancellables : Set<AnyCancellable> = []
    
    private var searchCompleter = MKLocalSearchCompleter()
    private var currentPromise : ((Result<[MKLocalSearchCompletion], Error>) -> Void)?
    
    override init() {
        super.init()
        searchCompleter.delegate = self
        
        $searchTerm
            .debounce(for: .seconds(0.5), scheduler: RunLoop.main)
            .removeDuplicates()
            .flatMap({ (currentSearchTerm) in
                self.searchTermToResults(searchTerm: currentSearchTerm)
            })
            .sink(receiveCompletion: { (completion) in
                //handle error
            }, receiveValue: { (results) in
                self.locationResults = results
            })
            .store(in: &cancellables)
    }
    
    func searchTermToResults(searchTerm: String) -> Future<[MKLocalSearchCompletion], Error> {
        Future { promise in
            self.searchCompleter.queryFragment = searchTerm
            self.currentPromise = promise
        }
    }
}

extension MapSearch : MKLocalSearchCompleterDelegate {
    func completerDidUpdateResults(_ completer: MKLocalSearchCompleter) {
            currentPromise?(.success(completer.results))
        }
    
    func completer(_ completer: MKLocalSearchCompleter, didFailWithError error: Error) {
        //could deal with the error here, but beware that it will finish the Combine publisher stream
        //currentPromise?(.failure(error))
    }
}

SwiftUI 界面，包括地图位置

struct ContentView: View {
    @StateObject private var mapSearch = MapSearch()
    
    var body: some View {
        NavigationView {
            Form {
                Section {
                    TextField("Address", text: $mapSearch.searchTerm)
                }
                Section {
                    ForEach(mapSearch.locationResults, id: \.self) { location in
                        NavigationLink(destination: Detail(locationResult: location)) {
                            VStack(alignment: .leading) {
                                Text(location.title)
                                Text(location.subtitle)
                                    .font(.system(.caption))
                            }
                        }
                    }
                }
            }.navigationTitle(Text("Address search"))
        }
    }
}

class DetailViewModel : ObservableObject {
    @Published var isLoading = true
    @Published private var coordinate : CLLocationCoordinate2D?
    @Published var region: MKCoordinateRegion = MKCoordinateRegion()
    
    var coordinateForMap : CLLocationCoordinate2D {
        coordinate ?? CLLocationCoordinate2D()
    }
    
    func reconcileLocation(location: MKLocalSearchCompletion) {
        let searchRequest = MKLocalSearch.Request(completion: location)
        let search = MKLocalSearch(request: searchRequest)
        search.start { (response, error) in
            if error == nil, let coordinate = response?.mapItems.first?.placemark.coordinate {
                self.coordinate = coordinate
                self.region = MKCoordinateRegion(center: coordinate, span: MKCoordinateSpan(latitudeDelta: 0.03, longitudeDelta: 0.03))
                self.isLoading = false
            }
        }
    }
    
    func clear() {
        isLoading = true
    }
}

struct Detail : View {
    var locationResult : MKLocalSearchCompletion
    @StateObject private var viewModel = DetailViewModel()
    
    struct Marker: Identifiable {
        let id = UUID()
        var location: MapMarker
    }
    
    var body: some View {
        Group {
            if viewModel.isLoading {
                Text("Loading...")
            } else {
                Map(coordinateRegion: $viewModel.region,
                    annotationItems: [Marker(location: MapMarker(coordinate: viewModel.coordinateForMap))]) { (marker) in
                    marker.location
                }
            }
        }.onAppear {
            viewModel.reconcileLocation(location: locationResult)
        }.onDisappear {
            viewModel.clear()
        }
        .navigationTitle(Text(locationResult.title))
    }
}

Answer 3

我的回答完全基于@George McDonnell 的回答。我希望它对执行最后一个有困难的人有所帮助。

import UIKit
import MapKit

class ViewController: UIViewController {

    @IBOutlet weak var searchBar: UISearchBar!
    @IBOutlet weak var tableVIew: UITableView!

    //create a completer
    lazy var searchCompleter: MKLocalSearchCompleter = {
        let sC = MKLocalSearchCompleter()
        sC.delegate = self
        return sC
    }()

    var searchSource: [String]?
}

extension ViewController: UISearchBarDelegate {
    func searchBar(_ searchBar: UISearchBar, textDidChange searchText: String) {
        //change searchCompleter depends on searchBar's text
        if !searchText.isEmpty {
            searchCompleter.queryFragment = searchText
        }
    }
}

extension ViewController: UITableViewDelegate, UITableViewDataSource {
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return searchSource?.count ?? 0
    }

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        //I've created SearchCell beforehand; it might be your cell type
        let cell = self.tableVIew.dequeueReusableCell(withIdentifier: "SearchCell", for: indexPath) as! SearchCell

        cell.label.text = self.searchSource?[indexPath.row]
//            + " " + searchResult.subtitle

        return cell
    }
}

extension ViewController: MKLocalSearchCompleterDelegate {
    func completerDidUpdateResults(_ completer: MKLocalSearchCompleter) {
        //get result, transform it to our needs and fill our dataSource
        self.searchSource = completer.results.map { $0.title }
        DispatchQueue.main.async {
            self.tableVIew.reloadData()
        }
    }

    func completer(_ completer: MKLocalSearchCompleter, didFailWithError error: Error) {
        //handle the error
        print(error.localizedDescription)
    }
}

Answer 4

此问题的示例项目可以从HERE下载

在这个示例项目中，这个问题是通过 MKLocalSearchRequest 和 MapKit 实现的。

它像谷歌地方 API 一样显示自动完成的地方，并且可以将注释点放置在 Apple 的地图上（不是在谷歌地图上，我希望只有你在寻找。）

但是，它显示的结果不如您从 Google Places API 获得的准确结果。问题在于地理编码数据库显然并不完整，而且苹果不是领导该领域的公司——谷歌才是。

附上一些示例应用的屏幕截图，以便您查看它是否对您的要求有用。

希望这就是你要找的东西！