How to use data from a structure array - ios

Question

I want to use the latitude and logitude values ​​in the structure array to represent polylines.
You can use the list[1].latitude value from json in the view, but if you try to use the list[1].latitude value from the override func viewDidLoad () above, you get an error.
How can I use this value as a polyline's latitude and longitude value?
Swift Source
import UIKit
import GoogleMaps
class TableController: UIViewController, GMSMapViewDelegate , UITableViewDataSource, UITableViewDelegate{
#IBOutlet weak var viewMap: GMSMapView!
#IBOutlet weak var listTableView: UITableView!
//JSON담을 구조
var list:[MyStruct] = [MyStruct]()
struct MyStruct
{
var index = ""
var ip = ""
var latitude = ""
var longitude = ""
var zonename = ""
init(_ index:String, _ ip:String, _ latitude:String, _ longitude:String, _ zonename:String)
{
self.index = index
self.ip = ip
self.latitude = latitude
self.longitude = longitude
self.zonename = zonename
}
}
override func viewDidLoad() {
super.viewDidLoad()
// set initial location
let camera: GMSCameraPosition = GMSCameraPosition.camera(withLatitude: 37.209037, longitude: 126.976370, zoom: 16.0)
viewMap.camera = camera
let count: Int = 0
//폴리라인
let path = GMSMutablePath()
path.add(CLLocationCoordinate2DMake(37.209037, 126.976370))
path.add(CLLocationCoordinate2DMake(37.211643, 126.972444))
path.add(CLLocationCoordinate2DMake(37.211457, 126.972147))
let polyline = GMSPolyline(path: path)
polyline.strokeWidth = 6.0
polyline.map = viewMap
listTableView.dataSource = self
listTableView.delegate = self
get_data("http://192.168.0.11/fence.php")
}
func get_data(_ link:String)
{
let url:URL = URL(string: link)!
let session = URLSession.shared
let request = URLRequest(url: url)
let task = session.dataTask(with: request, completionHandler: {
(data, response, error) in
self.extract_data(data)
})
task.resume()
}
func extract_data(_ data:Data?)
{
let json:Any?
if(data == nil)
{
return
}
do{
json = try JSONSerialization.jsonObject(with: data!, options: [])
}
catch
{
return
}
guard let data_array = json as? NSArray else
{
return
}
for i in 0 ..< data_array.count
{
if let data_object = data_array[i] as? NSDictionary
{
if let data_index = data_object["index"] as? String,
let data_ip = data_object["Ip"] as? String,
let data_latitude = data_object["Latitude"] as? String,
let data_longitude = data_object["Longitude"] as? String,
let data_Zonename = data_object["ZoneName"] as? String
{
list.append(MyStruct(data_index, data_ip, data_latitude, data_longitude, data_Zonename))
}
}
}
refresh_now()
}
func refresh_now()
{
DispatchQueue.main.async(
execute:
{
self.listTableView.reloadData()
})
}
public func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int
{
return list.count
}
public func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell
{
let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath)
cell.textLabel?.text = list[indexPath.row].zonename + " : " + list[indexPath.row].latitude
return cell
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}