MKLocalsearchRequest附近没有naturalLanguageQuery字符串的地方

Question

是否可以在不提供naturalLanguageQuery的情况下使用MKLocalSearchRequest显示附近的位置？

我知道典型的方法是使用foursquare或谷歌。两者我都用过

Answer 1

我已经尝试实现这一点一段时间了，但最接近的是使用for循环运行多个查询并将结果添加到主数组。效率低下，你有更多的成功吗？

Answer 2

您可以实现以下演示目的，但我不建议在生产应用程序中使用这种方法，因为它显然是不可伸缩的。

var nearbyPlaces: [MKMapItem] = []
let params: [String] = ["bar", "shop", "restaurant", "cinema"]
let request = MKLocalSearchRequest()
let span = MKCoordinateSpan(latitudeDelta: CLLocationDegrees(exactly: 1000)!, longitudeDelta: CLLocationDegrees(exactly: 1000)!)
let region = MKCoordinateRegion(center: coord, span: span)
request.region = region
for param in params {
        request.naturalLanguageQuery = param    
        let places = MKLocalSearch(request: request)
        places.start { [unowned self] response, error in
           guard let result = response else { return }
           self.nearbyPlaces.append(contentsOf: result.mapItems)
        }
}

Answer 3

我的策略是

1. 使用地理编码获取一个位置标记
2. 生成一个看起来不错的搜索文本（我对此没有信心）
3. 请求MKLocalSearch

伪代码在这里。

func placemark() async throws -> CLPlacemark? {
// (1)
    let geocoder: CLGeocoder = .init()
    let location: CLLocation = .init(
        latitude: coordinate.latitude,
        longitude: coordinate.longitude
    )
    return try await geocoder.reverseGeocodeLocation(location).first
}

func findNearbyMapItems() async {
    guard let placemark = placemark else {
        return
    }
// (2)
    let searchText: String = Array(Set([
        placemark.administrativeArea ?? "",
        placemark.subAdministrativeArea ?? "",
        placemark.locality ?? "",
    ])).joined(separator: " ").trimmingCharacters(in: .whitespacesAndNewlines)
// (3)
    let nearbyMeters: CLLocationDistance = 500
    let request = MKLocalSearch.Request()
    request.naturalLanguageQuery = searchText
    request.resultTypes = [.pointOfInterest]
    request.region = MKCoordinateRegion(
        center: center,
        latitudinalMeters: nearbyMeters,
        longitudinalMeters: nearbyMeters
    )
    let response = try await MKLocalSearch(request: request).start()
    return response.mapItems
}

另一种解决方案仅适用于POI。

func mapItemsNearbyPOIOnSystem(radius: CLLocationDistance = 500) async throws -> [MKMapItem] {
    let request: MKLocalPointsOfInterestRequest = .init(center: coordinate, radius: radius)
    let response = try await MKLocalSearch(request: request).start()
    return response.mapItems
}