CloudKit - How to modify the record in the background - ios

Question

My App can use location updates in the background now.
Then, can we modify the record in the background when a user is moving?
Code:
#IBOutlet weak var mapView: MKMapView!
var locationManager: CLLocationManager!
override func viewDidLoad() {
super.viewDidLoad()
mapView.delegate = self
locationManager = CLLocationManager()
locationManager.delegate = self
locationManager.requestAlwaysAuthorization()
locationManager.startUpdatingLocation()
locationManager.allowsBackgroundLocationUpdates = true
}
func locationManager(_ manager: CLLocationManager, didUpdateLocations locations:[CLLocation]) {
recordLocation()
}
func recordLocation() {
let publicDatabase = CKContainer.default().publicCloudDatabase
let predicate = NSPredicate(format: "accountID == %#", argumentArray: [myID!])
let query = CKQuery(recordType: "Accounts", predicate: predicate)
publicDatabase.perform(query, inZoneWith: nil, completionHandler: {(records, error) in
if let error = error {
print("error1: \(error)")
return
}
for record in records! {
record["currentLocation"] = self.mapView.userLocation.location
publicDatabase.save(record, completionHandler: {(record, error) in
if let error = error {
print("error2: \(error)")
return
}
print("success!")
})
}
})
}
image - Capability of Background Modes
By the way, everything is fine as long as my app runs in the foreground.
Versions
Xcode 12.2 / Swift 4.2
Summary
Could you please tell me how to modify the record in the background? In the first place, can we do that?
Thanks.

Answer 1

I misunderstood. I had already recorded my location in the background, but had failed to get the latest one.
record["currentLocation"] = self.mapView.userLocation.location
By using this code, I had recorded the location the last moment that I were viewing MKMapView.
In other words, the problem, recording in the background, have been solved from the beginning.
I rewrote as the following code:
func locationManager(_ manager: CLLocationManager, didUpdateLocations locations:[CLLocation]) {
if let location = locations.first {
recordLocation(currentLocation: location)
}
}
func recordLocation(currentLocation: CLLocation) {
let publicDatabase = CKContainer.default().publicCloudDatabase
let predicate = NSPredicate(format: "accountID == %#", argumentArray: [myID!])
let query = CKQuery(recordType: "Accounts", predicate: predicate)
publicDatabase.perform(query, inZoneWith: nil, completionHandler: {(records, error) in
if let error = error {
print("error1: \(error)")
return
}
for record in records! {
record["currentLocation"] = currentLocation as CLLocation
publicDatabase.save(record, completionHandler: {(record, error) in
if let error = error {
print("error2: \(error)")
return
}
print("success!: \(String(describing: currentLocation))")
})
}
})
}