I'm getting a BAD_EXC_ACCESS on line . The reason is "Attempting to load the view of a view controller while it is deallocating is not allowed and may result in undefined behavior".
func drawLocations(loc: CLLocation)
{
let center = CLLocationCoordinate2D(latitude: loc.coordinate.latitude, longitude: loc.coordinate.longitude)
let lat: CLLocationDegrees = center.latitude
let long: CLLocationDegrees = center.longitude
var points = [CLLocationCoordinate2DMake(lat,long),CLLocationCoordinate2DMake(lat,long),CLLocationCoordinate2DMake(lat,long),CLLocationCoordinate2DMake(lat,long)]
let polygon = MKPolygon(coordinates: &points, count: points.count)
mapView.addOverlay(polygon)//where I get error
}
func loadLocation(completion: (error:NSError?, records:[CKRecord]?) -> Void)
{
let query = CKQuery(recordType: "Location", predicate: NSPredicate(value: true))
CKContainer.defaultContainer().publicCloudDatabase.performQuery(query, inZoneWithID: nil){
(records, error) in
if error != nil {
print("error fetching locations: \(error)")
completion(error: error, records: nil)
} else {
print("found locations: \(records)")
print("found locations")
completion(error: nil, records: records)
guard let records = records else {
return
}
for(var i = 0; i<records.count; i += 1)
{
self.drawLocations(records[i]["location"] as! CLLocation)//where I call function
}
}
}
}
The completion block of performQuery "must be capable of running on any thread of the app" (as described in the docs). You call addOverlay which is a UI function, and so much be called on the main queue. You need to dispatch this method to the main queue.
Side note, unrelated to the question: for(var i = 0; i<records.count; i += 1) is much better written as for record in records. The C-style syntax is deprecated.
Related
So sometimes someone in entered the search radius is from before, ie someone who was in search radius, but based on the current data in the database is not in the radius. Other times, someone who wasn't in the search radius before but now is, doesn't get printed.
This only happens once each time, ie if I load the app for the second time after the erroneous inclusion or exclusion, the correct array prints.
func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
let databaseRef = Database.database().reference()
guard let uid = Auth.auth().currentUser?.uid else { return }
guard let locValue: CLLocationCoordinate2D = manager.location?.coordinate else { return }
print("locations = \(locValue.latitude) \(locValue.longitude)")
latestLocation = ["latitude" : locValue.latitude, "longitude" : locValue.longitude]
let lat = locValue.latitude
let lon = locValue.longitude
dict = CLLocation(latitude: lat, longitude: lon)
print("dict", dict)
if let locationDictionary = latestLocation {
databaseRef.child("people").child(uid).child("Coordinates").setValue(locationDictionary)
let geofireRef = Database.database().reference().child("Loc")
let geoFire = GeoFire(firebaseRef: geofireRef)
print(CLLocation(latitude: lat, longitude: lon),"GGG")
geoFire.setLocation(CLLocation(latitude: lat, longitude: lon), forKey: uid)
}
manager.stopUpdatingLocation()
}
Override func ViewdidLoad() {
super.viewDidLoad()
guard let uid = Auth.auth().currentUser?.uid else { return }
let geofireRef = Database.database().reference().child("Loc")
let geoFire = GeoFire(firebaseRef: geofireRef)
geoFire.getLocationForKey(uid) { (location, error) in
if (error != nil) {
print("An error occurred getting the location for \"Coordinates\": \(String(describing: error?.localizedDescription))")
} else if (location != nil) {
print("Location for \"Coordinates\" is [\(location?.coordinate.latitude), \(String(describing: location?.coordinate.longitude))]")
} else {
print("GeoFire does not contain a location for \"Coordinates\"")
}
}
let query1 = geoFire.query(at: self.dict, withRadius: 3)
query1.observe(.keyEntered, with: { key, location in
print("Key: " + key + "entered the search radius.") ///**this prints keys of users within 3 miles. This is where I see the wrong inclusions or exclusions**
do {
self.componentArray.append(key)
}
print(self.componentArray,"kr")
}
)
}
Here's what I would do for testing and maybe a solution. This is similar to your code but takes some of the unknowns out of the equation; I think we maybe running into an asynchronous issue as well, so give this a try.
In viewDidLoad get the current users position. That position will be used as the center point of the query
self.geoFire.getLocationForKey(uid) { (location, error) in
if (error != nil) {
print("An error occurred getting the location for \"Coordinates\": \(String(describing: error?.localizedDescription))")
} else if (location != nil) {
self.setupCircleQueryWith(center: location) //pass the known location
} else {
print("GeoFire does not contain a location for \"Coordinates\"")
}
}
Once the location var is populated within the closure (so you know it's valid) pass it to a function to generate the query
func setupCircleQueryWith(center: CLLLocation) {
var circleQuery = self.geoFire.queryAtLocation(center, withRadius: 3.0)
self.queryHandle = self.circleQuery.observe(.keyEntered, with: { key, location in
print("Key '\(key)' entered the search area and is at location '\(location)'")
self.myKeyArray.append(key)
})
}
self.queryHandle is a class var we can use to remove the query at a later time. I also set up self.geoFire as a class var that points to Loc.
EDIT
At the very top of your class, add a class var to store the keys
class ViewController: NSViewController, NSTableViewDelegate, NSTableViewDataSource {
var ref: DatabaseReference!
var myKeyArray = [String]()
let queryHandle: DatabaseHandle!
and remember to also add a .keyExited event so you will know when to remove a key from the array when the key exits the area.
The issue is that the code inside the completionHandler block is never run; I used breakpoints and the program would skip over the completion handler block in build mode
Below are two functions used within PinALandPlaceMark, where most of my code is located
func generateRandomWorldLatitude()-> Double{
let latitude = Double.random(in: -33 ..< 60)
return latitude
}
func generateRandomWorldLongitude()-> Double{
let longitude = Double.random(in: -180 ..< 180)
return longitude
}
func PinALandPlaceMark() -> MKAnnotation {
var LandBasedCountryHasYetToBeFound : (Bool, CLLocationDegrees?, CLLocationDegrees?)
LandBasedCountryHasYetToBeFound = (false,nil,nil)
let randomPinLocation = MKPointAnnotation()
repeat{
if LandBasedCountryHasYetToBeFound == (false,nil,nil){
let latitude: CLLocationDegrees = generateRandomWorldLatitude()
let longitude: CLLocationDegrees = generateRandomWorldLongitude()
let randomCoordinate = CLLocation(latitude: latitude, longitude: longitude)
let geocoder = CLGeocoder()
geocoder.reverseGeocodeLocation(randomCoordinate, completionHandler: { (placemarks, error) -> Void in
if error != nil{print(error)}else{
guard let placemark = placemarks?.first else{return}
//check which placemark property exists, store in the 0 alpha labelForClosure
if let countryExists = placemark.country {
LandBasedCountryHasYetToBeFound = (true,latitude,longitude)
//country = countryExists as String
// viewController.labelForClosure.text = countryExists
print(" Country Exists!: \(countryExists)")
print(" randomCoordinate \(randomCoordinate)")
}
}
})
}
// print("The country found was on land. This statement is \(LandBasedCountryHasYetToBeFound.occursInCountry)")
else{
let coordinatesOfrandomPinLocation = CLLocationCoordinate2D(latitude: LandBasedCountryHasYetToBeFound.1!, longitude: LandBasedCountryHasYetToBeFound.2!)
randomPinLocation.title = ""//LandBasedCountryHasYetToBeFound.countryName
randomPinLocation.coordinate = coordinatesOfrandomPinLocation
// viewController.mapView.addAnnotation(randomPinLocation)
}
}while LandBasedCountryHasYetToBeFound.0 == false
print("randomPin has been returned, now use pin function inside placemark declaration")
return randomPinLocation
}
Your main problem is that your CLGeocoder instance is held in a local variable inside the loop; This means that it will be released before it has completed its task.
You have a couple of other issues too which would cause you problems even if the reverse geo-coding did complete.
The main one is that you are checking for loop termination using a boolean that is set inside the closure; The closure will execute asynchronously, so the loop will have executed many more times before the boolean is set to true in the case where an address is found.
The second problem is related to and made worse by this; reverse geocoding is rate limited. If you submit too many requests too quickly, Apple's servers will simply return an error. Even if you did wait for the first response before submitting a second, your chances of hitting land at random are pretty low, so you will probably hit this limit pretty quickly.
Ignoring the rate limit problem for the moment, you can use a recursive function that accepts a completion handler rather than using a loop and trying to return a value.
var geoCoder = CLGeocoder()
func pinALandPlaceMark(completion: #escaping (Result<MKAnnotation, Error>) -> Void) {
let latitude: CLLocationDegrees = generateRandomWorldLatitude()
let longitude: CLLocationDegrees = generateRandomWorldLongitude()
let randomCoordinate = CLLocation(latitude: latitude, longitude: longitude)
geocoder.reverseGeocodeLocation(randomCoordinate) { (placemarks, error) in
guard error == nil else {
completion(nil,error)
return error
}
if let placemark = placemarks.first, let _ = placemark.country {
let randomPinLocation = MKPointAnnotation()
randomPinLocation.coordinate = randomCoordinate.coordinate
completionHandler(randomPinLocation,nil)
} else {
pinALandPlaceMark(completion:completion)
}
}
}
The first thing we do is declare a property to hold the CLGeocoder instance so that it isn't released.
Next, this code checks to see if a placemark with a country was returned. If not then the function calls itself, passing the same completion handler, to try again. If an error occurs then the completion handler is called, passing the error
To use it, you would say something like this:
pinALandPlaceMark() { result in
switch result {
case .success(let placemark):
print("Found \(placemark)")
case .failure(let error):
print("An error occurred: \(error)")
}
}
Using the following code I can calculate the distance between two addresses. Is it possible to add the ability to add more addresses to the mix to calculate the distance between 3 or more?
Code so far:
import Cocoa
import MapKit
import CoreLocation
import PlaygroundSupport
PlaygroundPage.current.needsIndefiniteExecution = true
let geocoder = CLGeocoder()
geocoder.geocodeAddressString("1 Pall Mall East, London SW1Y 5AU") { (placemarks: [CLPlacemark]? , error: Error?) in
if let placemarks = placemarks {
let start_placemark = placemarks[0]
geocoder.geocodeAddressString("Buckingham Palace, London SW1A 1AA", completionHandler: { ( placemarks: [CLPlacemark]?, error: Error?) in
if let placemarks = placemarks {
let end_placemark = placemarks[0]
// Okay, we've geocoded two addresses as start_placemark and end_placemark.
let start = MKMapItem(placemark: MKPlacemark(coordinate: start_placemark.location!.coordinate))
let end = MKMapItem(placemark: MKPlacemark(coordinate: end_placemark.location!.coordinate))
// Now we've got start and end MKMapItems for MapKit, based on the placemarks. Build a request for
// a route by car.
let request: MKDirectionsRequest = MKDirectionsRequest()
request.source = start
request.destination = end
request.transportType = MKDirectionsTransportType.automobile
// Execute the request on an MKDirections object
let directions = MKDirections(request: request)
directions.calculate(completionHandler: { (response: MKDirectionsResponse?, error: Error?) in
// Now we should have a route.
if let routes = response?.routes {
let route = routes[0]
print(route.distance) // 2,307 metres.
}
})
}
})
}
}
There are multiple ways to achieve this. Since you can make multiple requests at the same time and you need to wait for them I suggest you to create all of them simultaneously. When all return you should then return your result. There are many tools to achieve this but the most direct way is to simply create a counter. You start it with number of expected requests and then decrease it for every returned requests. Once the number turns to zero all are done. A simple example would be:
var count: Int = 10
for _ in 0..<count {
DispatchQueue.main.asyncAfter(deadline: .now() + .random(in: 1..<10)) {
count -= 1
if count == 0 {
print("All done here")
}
}
}
For your case you may want to restructure a bit. I think you should first geocode addresses to get all the placemarks. Then use array of placemarks to create pairs to use directions. Doing so will not duplicate for geocoding: Assume you are having 3 addresses A, B, C. Then to do pairs directly your would do distance(geocode(A), geocode(B)) + distance(geocode(B), geocode(C)) and you are geocoding B twice. So to avoid it rather do distance([A, B, C].map { geocode($0) }).
From your example this is what I got:
private static func generatePlacemarksFromAddresses(_ addresses: [String], completion: #escaping ((_ placemarks: [(address: String, placemark: MKPlacemark)]?, _ error: Error?) -> Void)) {
guard addresses.count > 0 else {
completion([], nil)
return
}
var requestsOut: Int = addresses.count
var placemarks: [String: MKPlacemark?] = [String: MKPlacemark?]()
addresses.forEach { address in
let geocoder = CLGeocoder()
geocoder.geocodeAddressString(address) { foundPlacemarks, error in
let placemark: MKPlacemark? = {
guard let location = foundPlacemarks?.first?.location else { return nil }
return MKPlacemark(coordinate: location.coordinate)
}()
placemarks[address] = placemark
requestsOut -= 1
if requestsOut == 0 {
// All are finished
// Compose ordered array or error
let erroredAddresses: [String] = placemarks.filter { $0.value == nil }.map { $0.key }
if erroredAddresses.count > 0 {
completion(nil, NSError(domain: "GEOCODING", code: 400, userInfo: ["dev_message": "Not all adresses could be geocoded. Failed with \(erroredAddresses.count) addressess: \(erroredAddresses.joined(separator: " & "))"]))
} else {
completion(addresses.map { ($0, placemarks[$0]!!) }, nil)
}
}
}
}
}
private static func calculateDirectionDistanceFromPlacemarks(_ placemarks: [(address: String, placemark: MKPlacemark)], completion: #escaping ((_ distance: Double?, _ error: Error?) -> Void)) {
guard placemarks.count > 1 else {
completion(0, nil)
return
}
var requestsOut: Int = placemarks.count-1
var overallDistance: Double = 0.0
var erroredConnections: [String] = [String]()
for index in 0..<placemarks.count-1 {
let directions = MKDirections(request: {
let request: MKDirections.Request = MKDirections.Request()
request.source = MKMapItem(placemark: placemarks[index].placemark)
request.destination = MKMapItem(placemark: placemarks[index+1].placemark)
request.transportType = MKDirectionsTransportType.automobile
return request
}())
directions.calculate(completionHandler: { (response: MKDirections.Response?, error: Error?) in
if let distance = response?.routes.first?.distance {
overallDistance += distance
} else {
erroredConnections.append(placemarks[index].address + " -> " + placemarks[index+1].address)
}
requestsOut -= 1
if requestsOut == 0 {
// All are done
if erroredConnections.count > 0 {
completion(nil, NSError(domain: "GEOCODING", code: 400, userInfo: ["dev_message": "Not all connections returned a route. Failed with \(erroredConnections.count) connections: \(erroredConnections.joined(separator: " & "))"]))
} else {
completion(overallDistance, nil)
}
}
})
}
}
And usage is pretty simple:
generatePlacemarksFromAddresses(["Ljubljana", "Canada", "1 Pall Mall East, London SW1Y 5AU", "Buckingham Palace, London SW1A 1AA", "1 Pall Mall East, London SW1Y 5AU"]) { placemarks, error in
guard let placemarks = placemarks else {
print("Placemarks could not be generated. Got error: \(error)")
return
}
calculateDirectionDistanceFromPlacemarks(placemarks) { distance, error in
if let distance = distance {
print("Got distance: \(distance)")
}
if let error = error {
print("Got error: \(error)")
}
}
}
Note that a given example produces an error because there is no root across Atlantic which is a valid result. To test with non-error example you can remove "Canada" and try with ["Ljubljana", "1 Pall Mall East, London SW1Y 5AU", "Buckingham Palace, London SW1A 1AA", "1 Pall Mall East, London SW1Y 5AU"].
i'm trying to use swift geocoding to get the city, but somehow the city only showup nested inside the method and when returned the variable is empty, here is the code i'm using.
class {
var locationManager = CLLocationManager()
var longitude = CLLocationDegrees()
var latitude = CLLocationDegrees()
var city = ""
override func viewDidLoad() {
super.viewDidLoad()
setupLocation()
var x = getLocation()
print("\n\n x your city is: \(x)\n\n"); // 'x' is always empty
if x == "paris" {
print("\n\n your city is: \(x)\n\n"); // 'x' is always empty
}
}
func getLocation() -> String {
longitude = (locationManager.location?.coordinate.longitude)!
latitude = (locationManager.location?.coordinate.latitude)!
let location = CLLocation(latitude: latitude, longitude: longitude)
print(location)
CLGeocoder().reverseGeocodeLocation(location, completionHandler: {(placemarks, error) -> Void in
print(location)
if error != nil {
print("Reverse geocoder failed with error" + error!.localizedDescription)
return
}
if placemarks!.count > 0 {
let pm = placemarks![0]
print("locality is \(pm.locality)")
self.city = pm.locality!
print(" city first \(self.city)") //contains a city
}
else {
print("Problem with the data received from geocoder")
}
})
print("city second \(city)") //empty every time
return city
}
}
As pointed out here, you have to add a completion handler to your method:
func getLocation(completion: #escaping (String) -> Void) {
longitude = (locationManager.location?.coordinate.longitude)!
latitude = (locationManager.location?.coordinate.latitude)!
let location = CLLocation(latitude: latitude, longitude: longitude)
print(location)
CLGeocoder().reverseGeocodeLocation(location, completionHandler: {(placemarks, error) -> Void in
print(location)
if error != nil {
print("Reverse geocoder failed with error" + error!.localizedDescription)
return
}
if placemarks!.count > 0 {
let pm = placemarks![0]
print("locality is \(pm.locality)")
completion(pm.locality!)
}
else {
print("Problem with the data received from geocoder")
}
})
}
And then just do:
getLocation() {
locality in
self.city = locality
}
You have stumbled upon a time issue. reverseGeocodeLocation is asynchronous, so the and the method returns before the closure is fully evaluated.
If you set breakpoints you would see that the
print("city second \(city)") //empty every time
line would trigger before the
print(" city first \(self.city)") //contains a city
one
Problem:
reverseGeocodeLocation is an asynchronous method (it doesn't evaluate immediately and would take time to evaluate). Before reverseGeocodeLocation is completed getLocation will be completed.
Solution:
Modify the getLocation to accept a closure as a parameter. Inside the completion handler of reverseGeocodeLocation call that closure and pass that value of the city
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.
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
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)
}
}
}