SwiftyJson 无法设置值

Question

我正在使用 Alamofire 获取卡车表。结果使用 SwiftyJSON 处理。其中一列是每辆卡车的坐标。

我想将卡车坐标与用户当前位置进行比较。我已经可以计算了。我正在考虑将计算出的距离作为一个新字段添加到同一个 JSONObject 中，目的是按距离排序，但我似乎根本无法设置一个新值。

设置 json 对象根本不起作用。下面是我的代码。我评论了它不起作用的部分。我没有收到警告或错误。如果我打印出来，我只会得到一个空白行。请帮忙。提前致谢。我做对了吗？考虑到结果中的卡车坐标和设备上的用户位置，关于如何最好地按距离对列表进行排序有什么建议吗？

 Alamofire.request(.POST, Ftf.endPoint(), parameters: params).responseJSON { response in

        if response.result.value != nil{
            let obj = JSON(response.result.value!)
            self.jsonObj = obj
            //ATTEMPT TO SORT THE JSON OBJECT
            print("Begin Sorting Object")
            print("User located at \(self.MyLocation)")

            for (key,subJson):(String, JSON) in self.jsonObj {
                let truckloc = subJson["truckLocation"].stringValue
                print("This truck is at \(truckloc)")

                let coords = truckloc
                var coord = coords.componentsSeparatedByString(",")
                let lat = coord[0]
                let lon = coord[1]
                let truckLocation: CLLocationCoordinate2D = CLLocationCoordinate2DMake((lat as NSString).doubleValue, (lon as NSString).doubleValue)
                let point1 = MKMapPointForCoordinate(self.MyLocation)
                let point2 = MKMapPointForCoordinate(truckLocation)
                let distance = MKMetersBetweenMapPoints(point1, point2)/1000
                let distanceStr = NSString(format: "%.1f", distance)

                print("Distance of truck from user is \(distanceStr)")

                //THIS LINE HERE DOESNT WORK. NO ERROR NO WARNINGS. JUST NOTHING HAPPENS
                self.jsonObj[key]["distance"].string = "\(distanceStr)"


            }

            self.activityIndicator.stopAnimating()
            self.tableView.reloadData()
            self.ftfRefresh.endRefreshing()
        }else{
            self.presentViewController(Ftf.generalAlert("No network connection found"), animated: true, completion: nil)
        }


    }

Answer 1

试试这个，

self.jsonObj[key]["distance"] = JSON("\(distanceStr)")

示例，

    var json = JSON(["1":"2"])

    print(json)

    json["1"] = JSON("3")

    print(json)

Answer 2

我还没有弄清楚为什么，但我似乎已经解决了我的问题。使用 self.jsonObj 后，我使用了本地 obj 并添加了该字段。完成后，我更新了全局 self.jsonObj。以下代码有效。键也作为字符串传递。我将其更改为 Int

 Alamofire.request(.POST, Ftf.endPoint(), parameters: params).responseJSON { response in

        if response.result.value != nil{
            var obj = JSON(response.result.value!)
                            //ATTEMPT TO SORT THE JSON OBJECT
            print("Begin Sorting Object")
            print("User located at \(self.MyLocation)")

            for (key,subJson):(String, JSON) in obj {
                let truckloc = subJson["truckLocation"].stringValue
                print("This truck is at \(truckloc)")

                let coords = truckloc
                var coord = coords.componentsSeparatedByString(",")
                let lat = coord[0]
                let lon = coord[1]
                let truckLocation: CLLocationCoordinate2D = CLLocationCoordinate2DMake((lat as NSString).doubleValue, (lon as NSString).doubleValue)
                let point1 = MKMapPointForCoordinate(self.MyLocation)
                let point2 = MKMapPointForCoordinate(truckLocation)
                let distance = MKMetersBetweenMapPoints(point1, point2)/1000
                let distanceStr = NSString(format: "%.1f", distance)

                print("Distance of truck from user is \(distanceStr)")

                //FINALLY IT WORKED

                obj[Int(key)!]["dist"].stringValue = distanceStr as String
                print(obj[Int(key)!]["dist"].stringValue)


            }

            self.jsonObj = obj



            self.activityIndicator.stopAnimating()
            self.tableView.reloadData()
            self.ftfRefresh.endRefreshing()
        }else{
            self.presentViewController(Ftf.generalAlert("No network connection found"), animated: true, completion: nil)
        }




    }