I want to save location coordinates into Core Data- what is the right way of storing these and retrieving them?
At the moment I am doing this and getting errors:
var newPlaceCoordinate = CLLocationCoordinate2D()
var newPlaceLatitude = CLLocationDegrees()
var newPlaceLongitude = CLLocationDegrees()
I get my coordinates from using Google maps API using the autocomplete widget.
let newPlaceCoordinate = place.coordinate
self.newPlaceCoordinate = place.coordinate
let newPlaceLatitude = place.coordinate.latitude
print(newPlaceLatitude)
self.newPlaceLatitude = place.coordinate.latitude
let newPlaceLongitude = place.coordinate.longitude
print(newPlaceLongitude)
self.newPlaceLongitude = place.coordinate.longitude
Then to store the coordinates I use:
let appDelegate = UIApplication.shared.delegate as! AppDelegate
let context = appDelegate.persistentContainer.viewContext
let newPlace = NSEntityDescription.insertNewObject(forEntityName: "StoredPlace", into: context)
newPlace.setValue(newPlaceCoordinate, forKey: "coordinate")
newPlace.setValue(newPlaceLatitude, forKeyPath: "latitude")
newPlace.setValue(newPlaceLongitude, forKeyPath: "longitude")
And I have the attributes all set as String types. Then to retrieve in my ViewDidLoad I have:
let appDelegate = UIApplication.shared.delegate as! AppDelegate
let context = appDelegate.persistentContainer.viewContext
let request = NSFetchRequest<NSFetchRequestResult>(entityName: "StoredPlace")
request.returnsObjectsAsFaults = false
if let coordinate = result.value(forKey: "coordinate") as? String
{
let latitude = (coordinate as NSString).doubleValue
let longitude = (coordinate as NSString).doubleValue
let markers = GMSMarker()
markers.position = CLLocationCoordinate2D(latitude: latitude, longitude: longitude)
markers.icon = GMSMarker.markerImage(with: UIColor.yellow)
markers.tracksViewChanges = true
markers.map = vwGMap
}
So this is not working and producing an error of 'attribute: property = "coordinate"; desired type = NSString; given type = NSConcreteValue'. I have a few questions.
How do I save a coordinate data appropriately? Do I save it as a CLLocationDegrees or CLLocationCoordinate2D? How do I convert these objects into NSString or should I be using a different type in my attributes? (I tried changing it to Double or Integer but it also produced errors). I have multiple location coordinates which I would want to store and retrieve from core data.
If you are going to deal with lots of data, then CoreData is the best bet.
These are my attributes in
StorePlace
entity, its best to save only latitude and longitude and create coordinates from them when needed in your implementation.And to insert new data, I will do
After retrieving latitude, longitude you can use coordinate in your implementations as