如何使Firestore的GeoPoint符合Swifts可编码协议?

你可以像这样把你的声明作为一个地质点:

struct Landmark: Codable {
    let name: String
    let location: GeoPoint
}

但是你必须在你的文件中添加这个扩展名,让Swift知道Firebase的地质点的结构。

import FirebaseFirestore

fileprivate protocol CodableGeoPoint: Codable {
  var latitude: Double { get }
  var longitude: Double { get }

  init(latitude: Double, longitude: Double)
}

fileprivate enum GeoPointKeys: String, CodingKey {
  case latitude
  case longitude
}

extension CodableGeoPoint {
  public init(from decoder: Decoder) throws {
    let container = try decoder.container(keyedBy: GeoPointKeys.self)
    let latitude = try container.decode(Double.self, forKey: .latitude)
    let longitude = try container.decode(Double.self, forKey: .longitude)
    self.init(latitude: latitude, longitude: longitude)
  }

  public func encode(to encoder: Encoder) throws {
    var container = encoder.container(keyedBy: GeoPointKeys.self)
    try container.encode(latitude, forKey: .latitude)
    try container.encode(longitude, forKey: .longitude)
  }
}

extension GeoPoint: CodableGeoPoint {}

extension GeoPoint: Codable {
// custom codable implementation
}