ios - 如何遍历 JSON 坐标并将注释构建为一个函数？

Question

我正在努力获取使用 JSON 数据放置的注释。我曾尝试将 JSON 中的坐标迭代到一个新数组中，但是当我尝试将一个数组传递到我需要坐标的位置时，它失败了，因为它不能使用数组。我该如何解决这个问题？

有人能帮忙吗？

    Alamofire.request(.GET, "https://demo1991046.mockable.io/score/locations").responseJSON { (responseData) -> Void in
        let swiftyJsonVar = JSON(responseData.result.value!)

        if let resData = swiftyJsonVar["users"].arrayObject as? [NSArray] {
            self.newArray = (resData as? [NSArray])


        }
       print("\([self.newArray])")






        for var i = 0; i < self.newArray!.count; ++i {



            self.longitude.append(self.newArray[i]["lon"] as! String!)
            print("longitude: \(self.longitude)")

            self.latitude.append(self.newArray[i]["lat"] as! String!)
            print("latitude: \(self.latitude)")
        }

        let doubleLat = self.latitude.map {
            Double(($0 as NSString).doubleValue)
        }

        let doubleLon = self.longitude.map {
            Double(($0 as NSString).doubleValue)
        }

        print("doublelat: \(doubleLat)")
        print("doubleLon: \(doubleLon)")

        // 1
   self.locationManager.delegate = self
        // 2
   self.locationManager.requestAlwaysAuthorization()
        // 3
        let theSpan:MKCoordinateSpan = MKCoordinateSpanMake(0.01 , 0.01)
        let location:CLLocationCoordinate2D = CLLocationCoordinate2D(latitude: doubleLat, longitude: doubleLon) // <- here is where I get an error: "Cannot convert value of type '[Double]' to expect argument type 'CLLocationDegrees' (aka 'Double")"
        //        print("lat: \((locationManager.location?.coordinate.latitude)!)")
        //        print("lon: \((locationManager.location?.coordinate.longitude)!)")
        let theRegion:MKCoordinateRegion = MKCoordinateRegionMake(location, theSpan)

        self.mapView.setRegion(theRegion, animated: true)

        let anotation = MKPointAnnotation()
        anotation.coordinate = location
        anotation.title = "The Location"
        anotation.subtitle = "This is the location !!!"
        self.mapView.addAnnotation(anotation)

    }
}

Answer 1

我已经对您的代码进行了下面的 soem 修改

• 没有将 json 转换为 NSArray(使用 .array 而不是 .arrayObject)
• 移动了在 for 循环内向 map 添加注释以添加所有注释。
• 将区域设置移至 for 循环之外的 map ，并留给您设置您喜欢的位置。

---

 Alamofire.request(.GET, "https://demo1991046.mockable.io/score/locations").responseJSON { (responseData) -> Void in
        let swiftyJsonVar = JSON(responseData.result.value!)
        // get the users from the json var, no need to convert it to Array
        guard let usersJsonArray = swiftyJsonVar["users"].array else {
           // users not found in the json
           return
       }
        // the usersJsonArray is array of json which will be much easier for work with.
         // No need for 1,2 and 3 to be in the for loop.
         // 1
        self.locationManager.delegate = self
        // 2
        self.locationManager.requestAlwaysAuthorization()
        // 3
        let theSpan:MKCoordinateSpan = MKCoordinateSpanMake(0.01 , 0.01)

        for userJson in usersJsonArray {

            let longitudeString = userJson["lon"].stringValue
            print("longitude: \(longitudeString)")

            let latitudeString = userJson["lat"].stringValue
            print("latitude: \(latitudeString)")

           let doubleLat = Double(latitudeString)
           let doubleLon = Double(longitudeString)

           print("doublelat: \(doubleLat)")
           print("doubleLon: \(doubleLon)")

           // by having the next code block inside the for loop you will be able to add all the user locations to the map as anotations.
           let location:CLLocationCoordinate2D = CLLocationCoordinate2D(latitude: doubleLat, longitude: doubleLon) // Now should work fine

           let anotation = MKPointAnnotation()
           anotation.coordinate = location
           anotation.title = "The Location"
           anotation.subtitle = "This is the location !!!"
           self.mapView.addAnnotation(anotation)
    } // for usersJson

    // you need to figure out the loaction you will set for the mapView region.
    let location = .... // set the location you like. 
    let theRegion:MKCoordinateRegion = MKCoordinateRegionMake(location, theSpan)
    self.mapView.setRegion(theRegion, animated: true)
}