Create MapKit Circle overlay from multiple CloudKit records - ios

Question

I've been trying to add a new map view to my app which shows an overlay of all of the Geofenced regions in my CloudKit database.
At the moment I'm able to create pins from each of the locations with the following code.
func fetchData() {
let predicate = NSPredicate(format: "TRUEPREDICATE", argumentArray: nil)
let query = CKQuery(recordType: "Collection", predicate: predicate)
let operation = CKQueryOperation(query: query)
operation.desiredKeys = ["Location"]
operation.recordFetchedBlock = { (record : CKRecord) in
self.collectionLocation = record.objectForKey("Location") as? CLLocation
print(self.collectionLocation?.coordinate.latitude)
self.buildBubbles()
}
publicDB!.addOperation(operation)
operation.queryCompletionBlock = {(cursor, error) in
dispatch_async(dispatch_get_main_queue()) {
if error == nil {
} else {
print("error description = \(error?.description)")
}
}
}
}
func buildBubbles() {
if CLLocationManager.isMonitoringAvailableForClass(CLCircularRegion.self) {
let intrepidLat: CLLocationDegrees = (self.collectionLocation?.coordinate.latitude)!
let intrepidLong: CLLocationDegrees = (self.collectionLocation?.coordinate.longitude)!
let title = "Item"
let coordinate = CLLocationCoordinate2DMake(intrepidLat, intrepidLong)
let regionRadius = 300.0
let region = CLCircularRegion(center: CLLocationCoordinate2D(latitude: coordinate.latitude,
longitude: coordinate.longitude), radius: regionRadius, identifier: title)
self.locationManager.startMonitoringForRegion(region)
let restaurantAnnotation = MKPointAnnotation()
restaurantAnnotation.coordinate = coordinate;
restaurantAnnotation.title = "\(title)"
self.mapView.addAnnotation(restaurantAnnotation)
// Overlay code goes here
}
else {
print("System can't track regions")
}
}
But when I go to add the overlay:
let circle = MKCircle(centerCoordinate: coordinate, radius: regionRadius)
self.mapView.addOverlay(circle)
The app fails with error:
"This application is modifying the autolayout engine from a background
thread, which can lead to engine corruption and weird crashes. This
will cause an exception in a future release."
My guess is that I'm doing too much inside the background thread but when I move the "buildBubbles" function into the main queue it adds the circle overlay but only adds one of the Locations to the map.
Thanks for taking the time to look I would really appreciate any help.

Answer 1

Your interface into the bubbles function only provides for holding one location. Try changing the interface, such as to an array, and then see what you get. You will also need to worry about how you actually synchronize one versus the other

Answer 2

I did as Feldur suggested and created an array from the CloudKit Data then moved the MapKit set up from the background thread.
func fetchBubble() {
let query = CKQuery(recordType: "Collection", predicate: NSPredicate(format: "TRUEPREDICATE", argumentArray: nil))
publicDB!.performQuery(query, inZoneWithID: nil) { results, error in
if error == nil {
for collection in results! {
let collectionLocation = collection.valueForKey("Location") as? CLLocation
let collectionName = collection.valueForKey("Name") as! String
dispatch_async(dispatch_get_main_queue(), { () -> Void in
if CLLocationManager.isMonitoringAvailableForClass(CLCircularRegion.self) {
let intrepidLat: CLLocationDegrees = (collectionLocation?.coordinate.latitude)!
let intrepidLong: CLLocationDegrees = (collectionLocation?.coordinate.longitude)!
let title = collectionName
let coordinate = CLLocationCoordinate2DMake(intrepidLat, intrepidLong)
let regionRadius = 50.0
let region = CLCircularRegion(center: CLLocationCoordinate2D(latitude: coordinate.latitude,
longitude: coordinate.longitude), radius: regionRadius, identifier: title)
self.locationManager.startMonitoringForRegion(region)
let restaurantAnnotation = MKPointAnnotation()
self.mapView.addAnnotation(restaurantAnnotation)
restaurantAnnotation.coordinate = coordinate
let circle = MKCircle(centerCoordinate: coordinate, radius: regionRadius)
self.mapView.addOverlay(circle)
self.numberOfObjectsInMyArray()
}
else {
print("System can't track regions")
}
})
}
}
else {
print(error)
}
}
}