How do I iterate through JSON co-ordinates and build annotations as one function? - ios

Question

I am struggling to get the annotations being placed using JSON data. I have tried iterating the coordinates from the JSON into a new array but when I try pass an array to where I need the coordinates it fails because it cannot take arrays. How can I fix this?
Can anyone help?
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

I have done soem modifies below to your code
Didn't convert the json to NSArray (by using .array instead of .arrayObject)
moved adding anotation to the map inside the for loop to add all of them.
Moved setting a region to the map out side the for loop and left it to you to set the location you like.
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)
}