Get multiple strings from JSON - ios

Question

So the JSON variable let json = JSON(nearbyChargingSites.jsonString!) contains the current data.:
{
"timestamp" : 1626902257093,
"superchargers" : [
{
"location" : {
"lat" : 63.325319,
"long" : 10.305137
},
"total_stalls" : 19,
"distance_miles" : 10.064082000000001,
"type" : "supercharger",
"site_closed" : false,
"available_stalls" : 15,
"name" : "Leinstrand, Norway - Klett"
},
{
"location" : {
"lat" : 63.466445999999998,
"long" : 10.91766
},
"total_stalls" : 16,
"distance_miles" : 11.838984999999999,
"type" : "supercharger",
"site_closed" : false,
"available_stalls" : 16,
"name" : "Stjørdal, Norway"
},
{
"location" : {
"lat" : 63.734355000000001,
"long" : 11.281487
},
"total_stalls" : 12,
"distance_miles" : 31.206503999999999,
"type" : "supercharger",
"site_closed" : false,
"available_stalls" : 11,
"name" : "Levanger, Norway"
},
{
"location" : {
"lat" : 62.832030000000003,
"long" : 10.009639999999999
},
"total_stalls" : 20,
"distance_miles" : 44.117753,
"type" : "supercharger",
"site_closed" : false,
"available_stalls" : 17,
"name" : "Berkåk, Norway"
}
],
"congestion_sync_time_utc_secs" : 1626902199,
"destination_charging" : [
{
"distance_miles" : 23.366278999999999,
"name" : "Bårdshaug Herregård",
"location" : {
"lat" : 63.299208,
"long" : 9.8448650000000004
},
"type" : "destination"
},
{
"distance_miles" : 38.390034,
"name" : "Fosen Fjordhotel",
"location" : {
"lat" : 63.959356999999997,
"long" : 10.223908
},
"type" : "destination"
},
{
"distance_miles" : 46.220022999999998,
"name" : "Falksenteret",
"location" : {
"lat" : 63.293301999999997,
"long" : 9.0834460000000004
},
"type" : "destination"
},
{
"distance_miles" : 54.981445000000001,
"name" : "Væktarstua",
"location" : {
"lat" : 62.908683000000003,
"long" : 11.893306000000001
},
"type" : "destination"
}
]
}
I use SwiftyJSON and tries to get the superchargers latitude, longitude and name, like this:
let jsonName = json["superchargers"]["name"]
let jsonLat = json["superchargers"]["location"]["lat"]
let jsonLong = json["superchargers"]["location"]["long"]
When trying to print any of those, all of them return nil.
Any ideas what I am doing wrong, and how to do this?
The reason I want to do this is because I want to add them as annotation to a MKMapView.

Answer 1

The first error is that the JSON initializer you are using will create a single JSON string object, it will not parse the string as JSON data:
Instead of:
let json = JSON(nearbyChargingSites.jsonString!)
you need to use:
let json = JSON(data: dataFromJSONString)
Second you need to iterate over the superchargers array to collect all the values
Try something like:
if let dataFromString = nearbyChargingSites.jsonString!.data(using: .utf8, allowLossyConversion: false) {
let json = try! JSON(data: dataFromString,options: .allowFragments)
for supercharger in json["superchargers"].arrayValue {
let jsonName = supercharger["name"].stringValue
let jsonLat = supercharger["location"]["lat"].doubleValue
let jsonLong = supercharger["location"]["long"].doubleValue
}
}
Please note that the above code does not perform error handling and will crash if values are missing from JSON.