A have a problem in my app. When i initialize the app on the first ViewController i get some data from my Firebase server using this code and a object called "By" and an array of objects called "byer":
func download() {
byer.removeAll()
self.Handle = self.ref?.child("Byer").observe(.childAdded, with: { (snapshot) in
if let dictionary = snapshot.value as? [String: AnyObject] {
let by = By()
by.Latitude = dictionary["Latitude"]?.doubleValue
by.Longitude = dictionary["Longitude"]?.doubleValue
by.Name = snapshot.key
let coordinate = CLLocation(latitude: by.Latitude!, longitude: by.Longitude!)
let distanceInMeter = coordinate.distance(from: self.locationManager.location!)
by.Distance = Int(distanceInMeter)
byer.append(by)
byer = byer.sorted(by: {$0.Distance! < $1.Distance! })
DispatchQueue.main.async {
selectedCity = byer[0].Name!
self.performSegue(withIdentifier: "GoToMain", sender: nil)
}
}
})
}
This all works fine. But the problem comes when i later in the app chance the value in the database. I use a button with this code:
if byTextfield.text != "" && latitude != nil && longitude != nil {
ref?.child("Byer").child(byTextfield.text!).child("Latitude").setValue(latitude)
ref?.child("Byer").child(byTextfield.text!).child("Longitude").setValue(longitude)
}
But for some reason the app crashes and a red line comes over the line:
let coordinate = CLLocation(latitude: by.Latitude!, longitude: by.Longitude!)
From the download function in the top. And the text:
"Thread 1: Fatal error: Unexpectedly found nil while unwrapping an Optional value.".
I have tried to remove the observer using:
override func viewDidDisappear(_ animated: Bool) {
self.ref?.removeObserver(withHandle: self.Handle)
}
But this dosn't seems to help. Any suggestions?
using guard statement you can easily handle the nil value of the longitude and latitude. i.e
func download() {
byer.removeAll()
self.Handle = self.ref?.child("Byer").observe(.childAdded, with: { (snapshot) in
if let dictionary = snapshot.value as? [String: AnyObject] {
let by = By()
guard let latitude = dictionary["Latitude"]?.doubleValue,let longitude =
dictionary["Longitude"]?.doubleValue else
{
return
}
by.Latitude = latitude
by.Longitude = longitude
by.Name = snapshot.key
let coordinate = CLLocation(latitude: by.Latitude!, longitude: by.Longitude!)
let distanceInMeter = coordinate.distance(from: self.locationManager.location!)
by.Distance = Int(distanceInMeter)
byer.append(by)
byer = byer.sorted(by: {$0.Distance! < $1.Distance! })
DispatchQueue.main.async {
selectedCity = byer[0].Name!
self.performSegue(withIdentifier: "GoToMain", sender: nil)
}
}
})
}
and if you want to unregister the observer from the firebase database reference then remove the database handler at the end of the childadded block.
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.
I'm trying to store to UserDefaults an array of CCLocationCoordinates from the tracking portion of my app paired with the name of the tracked route as key, to be able to recall it later on to use it within a function.
The problem is that when I call that function I get the index out of range error. I checked and the array is empty.
As I'm new to user defaults I tried to see other similar posts but they're all about NSUserDefaults and didn't find a solution.
Heres the code for the functions for storing and recalling the array:
func stopTracking2() {
self.trackingIsActive = false
self.trackigButton.backgroundColor = UIColor.yellow
locationManager.stopUpdatingLocation()
let stopRoutePosition = RouteAnnotation(title: "Route Stop", coordinate: (locationManager.location?.coordinate)!, imageName: "Route Stop")
self.actualRouteInUseAnnotations.append(stopRoutePosition)
print(actualRouteInUseCoordinatesArray)
print(actualRouteInUseAnnotations)
drawRoutePolyline() // draw line to show route
// checkAlerts2() // check if there is any notified problem on our route and marks it with a blue circle, now called at programmed checking
saveRouteToUserDefaults()
postRouteToAnalitics() // store route anonymously to FIrebase
}
func saveRouteToUserDefaults() {
// save actualRouteInUseCoordinatesArray : change for function
// userDefaults.set(actualRouteInUseCoordinatesArray, forKey: "\(String(describing: userRoute))")
storeCoordinates(actualRouteInUseCoordinatesArray)
}
// Store an array of CLLocationCoordinate2D
func storeCoordinates(_ coordinates: [CLLocationCoordinate2D]) {
let locations = coordinates.map { coordinate -> CLLocation in
return CLLocation(latitude: coordinate.latitude, longitude: coordinate.longitude)
}
let archived = NSKeyedArchiver.archivedData(withRootObject: locations)
userDefaults.set(archived, forKey: "\(String(describing: userRoute))")
userDefaults.synchronize()
}
func loadRouteFromUserDefaults() {
// gets entry from userRouteArray stored in userDefaults and append them into actualRouteInUseCoordinatesArray
actualRouteInUseCoordinatesArray.removeAll()
actualRouteInUseCoordinatesArray = userDefaults.object(forKey: "\(String(describing: userRoute))") as? [CLLocationCoordinate2D] ?? [CLLocationCoordinate2D]() // here we get the right set of coordinates for the route we are about to do the check on
// load route coordinates from UserDefaults
// actualRouteInUseCoordinatesArray = loadCoordinates()! //error found nil
}
// Return an array of CLLocationCoordinate2D
func loadCoordinates() -> [CLLocationCoordinate2D]? {
guard let archived = userDefaults.object(forKey: "\(String(describing: userRoute))") as? Data,
let locations = NSKeyedUnarchiver.unarchiveObject(with: archived) as? [CLLocation] else {
return nil
}
let coordinates = locations.map { location -> CLLocationCoordinate2D in
return location.coordinate
}
return coordinates
}
}
extension NewMapViewController {
// ALERTS :
func checkAlerts2() {
loadRouteFromUserDefaults() //load route coordinates to check in
// CHECK IF ANY OBSTACLE IS OUN OUR ROUTE BY COMPARING DISTANCES
while trackingCoordinatesArrayPosition != ( (actualRouteInUseCoordinatesArray.count) - 1) {
print("checking is started")
print(actualRouteInUseCoordinatesArray)
let trackingLatitude = actualRouteInUseCoordinatesArray[trackingCoordinatesArrayPosition].latitude
let trackingLongitude = actualRouteInUseCoordinatesArray[trackingCoordinatesArrayPosition].longitude
let alertLatitude = alertNotificationCoordinatesArray[alertNotificationCoordinatesArrayPosition].latitude
let alertLongitude = alertNotificationCoordinatesArray[alertNotificationCoordinatesArrayPosition].longitude
let coordinateFrom = CLLocation(latitude: trackingLatitude, longitude: trackingLongitude)
let coordinateTo = CLLocation(latitude: alertLatitude, longitude: alertLongitude)
let coordinatesDistanceInMeters = coordinateFrom.distance(from: coordinateTo)
// CHECK SENSITIVITY: sets the distance in meters for an alert to be considered an obstacle
if coordinatesDistanceInMeters <= 10 {
print( "found problem")
routeObstacle.append(alertNotificationCoordinatesArray[alertNotificationCoordinatesArrayPosition]) // populate obstacles array
trackingCoordinatesArrayPosition = ( trackingCoordinatesArrayPosition + 1)
}
else if alertNotificationCoordinatesArrayPosition < ((alertNotificationCoordinatesArray.count) - 1) {
alertNotificationCoordinatesArrayPosition = alertNotificationCoordinatesArrayPosition + 1
}
else if alertNotificationCoordinatesArrayPosition == (alertNotificationCoordinatesArray.count - 1) {
trackingCoordinatesArrayPosition = ( trackingCoordinatesArrayPosition + 1)
alertNotificationCoordinatesArrayPosition = 0
}
}
findObstacles()
NewMapViewController.checkCounter = 0
displayObstacles()
}
In the extension you can see the function that uses the array.
Right after the print of the array I get the index out of range error.
Thanks as usual to the community.
After trying various solutions offered I decided to rewrite the whole thing.
So after finding a post on how to code/decode my array to string I decided it was the way to go. It shouldn't be heavy on the system as it's a string that gets saved. Please let me know what you think of this solution.
Thank to #Sh_Khan to point out it was a decoding issue, and to #Moritz to point out I was performing a bad practice.
So the code is:
func storeRoute() {
// first we code the CLLocationCoordinate2D array to string
// second we store string into userDefaults
userDefaults.set(encodeCoordinates(coords: actualRouteInUseCoordinatesArray), forKey: "\(String(describing: NewMapViewController.userRoute))")
}
func loadRoute() {
//first se load string from user defaults
let route = userDefaults.string(forKey: "\(String(describing: NewMapViewController.userRoute))")
print("loaded route is \(route!))")
//second we decode it into CLLocationCoordinate2D array
actualRouteInUseCoordinatesArray = decodeCoordinates(encodedString: route!)
print("decoded route array is \(actualRouteInUseCoordinatesArray))")
}
func encodeCoordinates(coords: [CLLocationCoordinate2D]) -> String {
let flattenedCoords: [String] = coords.map { coord -> String in "\(coord.latitude):\(coord.longitude)" }
let encodedString: String = flattenedCoords.joined(separator: ",")
return encodedString
}
func decodeCoordinates(encodedString: String) -> [CLLocationCoordinate2D] {
let flattenedCoords: [String] = encodedString.components(separatedBy: ",")
let coords: [CLLocationCoordinate2D] = flattenedCoords.map { coord -> CLLocationCoordinate2D in
let split = coord.components(separatedBy: ":")
if split.count == 2 {
let latitude: Double = Double(split[0]) ?? 0
let longitude: Double = Double(split[1]) ?? 0
return CLLocationCoordinate2D(latitude: latitude, longitude: longitude)
} else {
return CLLocationCoordinate2D()
}
}
return coords
}
Rather than using heavy-weight objectiv-c-ish NSKeyed(Un)Archiver and making a detour via CLLocation I recommend to extend CLLocationCoordinate2D to adopt Codable
extension CLLocationCoordinate2D : Codable {
public init(from decoder: Decoder) throws {
var arrayContainer = try decoder.unkeyedContainer()
if arrayContainer.count == 2 {
let lat = try arrayContainer.decode(CLLocationDegrees.self)
let lng = try arrayContainer.decode(CLLocationDegrees.self)
self.init(latitude: lat, longitude: lng)
} else {
throw DecodingError.dataCorruptedError(in: arrayContainer, debugDescription: "Coordinate array must contain two items")
}
}
public func encode(to encoder: Encoder) throws {
var arrayContainer = encoder.unkeyedContainer()
try arrayContainer.encode(contentsOf: [latitude, longitude])
}
}
and replace the methods to load and save data with
func storeCoordinates(_ coordinates: [CLLocationCoordinate2D]) throws {
let data = try JSONEncoder().encode(coordinates)
UserDefaults.standard.set(data, forKey: String(describing: userRoute))
}
func loadCoordinates() -> [CLLocationCoordinate2D] {
guard let data = UserDefaults.standard.data(forKey: String(describing: userRoute)) else { return [] }
do {
return try JSONDecoder().decode([CLLocationCoordinate2D].self, from: data)
} catch {
print(error)
return []
}
}
storeCoordinates throws it hands over a potential encoding error
Load the data with
actualRouteInUseCoordinatesArray = loadCoordinates()
and save it
do {
try storeCoordinates(actualRouteInUseCoordinatesArray)
} catch { print(error) }
Your problem is that you save it as data and try to read directly without unarchiving , You can try
let locations = [CLLocation(latitude: 123, longitude: 344),CLLocation(latitude: 123, longitude: 344),CLLocation(latitude: 123, longitude: 344)]
do {
let archived = try NSKeyedArchiver.archivedData(withRootObject: locations, requiringSecureCoding: true)
UserDefaults.standard.set(archived, forKey:"myKey")
// read savely
if let data = UserDefaults.standard.data(forKey: "myKey") {
let saved = try NSKeyedUnarchiver.unarchiveTopLevelObjectWithData(data) as! [CLLocation]
print(saved)
}
}
catch {
print(error)
}
I am trying to sort my array by distance. I already have everything hooked up to grab the distance's but unsure how to sort from closest to furthest from the users location. I've used the below code for MKMapItem's yet unsure how to apply to my current array.
func sortMapItems() {
self.mapItems = self.mapItems.sorted(by: { (b, a) -> Bool in
return self.userLocation.location!.distance(from: a.placemark.location!) > self.userLocation.location!.distance(from: b.placemark.location!)
})
}
Firebase Call
databaseRef.child("Businesses").queryOrdered(byChild: "businessName").observe(.childAdded, with: { (snapshot) in
let key = snapshot.key
if(key == self.loggedInUser?.uid) {
print("Same as logged in user, so don't show!")
} else {
if let locationValue = snapshot.value as? [String: AnyObject] {
let lat = Double(locationValue["businessLatitude"] as! String)
let long = Double(locationValue["businessLongitude"] as! String)
let businessLocation = CLLocation(latitude: lat!, longitude: long!)
let latitude = self.locationManager.location?.coordinate.latitude
let longitude = self.locationManager.location?.coordinate.longitude
let userLocation = CLLocation(latitude: latitude!, longitude: longitude!)
let distanceInMeters : Double = userLocation.distance(from: businessLocation)
let distanceInMiles : Double = ((distanceInMeters.description as String).doubleValue * 0.00062137)
let distanceLabelText = "\(distanceInMiles.string(2)) miles away"
var singleChildDictionary = locationValue
singleChildDictionary["distanceLabelText"] = distanceLabelText as AnyObject
self.usersArray.append(singleChildDictionary as NSDictionary)
/*
func sortMapItems() {
self.mapItems = self.mapItems.sorted(by: { (b, a) -> Bool in
return self.userLocation.location!.distance(from: a.placemark.location!) > self.userLocation.location!.distance(from: b.placemark.location!)
})
}
*/
}
//insert the rows
self.followUsersTableView.insertRows(at: [IndexPath(row:self.usersArray.count-1,section:0)], with: UITableViewRowAnimation.automatic)
}
}) { (error) in
print(error.localizedDescription)
}
}
First make these changes in your code
singleChildDictionary["distanceInMiles"] = distanceInMiles
Then you can sort it like this:
self.usersArray = self.usersArray.sorted {
!($0["distanceInMiles"] as! Double > $1["distanceInMiles"] as! Double)
}
So I had issues previously working with 'observe' from firebase, and I realised I could not bring the variable values from inside the code block that was working asynchronously. A user told me to use completion handlers to resolve this issue, and his example was:
func mapRegion(completion: (MKCoordinateRegion)->()) {
databaseHandle = databaseRef.child("RunList").child(runName).observe(.value, with: { (snapshot) in
let runData = snapshot.value as? [String: AnyObject]
self.minLat = runData?["startLat"] as? Double
self.minLng = runData?["startLong"] as? Double
self.maxLat = runData?["endLat"] as? Double
self.maxLng = runData?["endLong"] as? Double
print("testing")
print(self.minLat!)
print(self.maxLng!)
let region = MKCoordinateRegion(
center: CLLocationCoordinate2D(latitude: (self.minLat! + self.maxLat!)/2,
longitude: (self.minLng! + self.maxLng!)/2),
span: MKCoordinateSpan(latitudeDelta: (self.maxLat! - self.minLat!)*1.1,
longitudeDelta: (self.maxLng! - self.minLng!)*1.1))
completion(region)
})
}
and to use the code:
mapRegion() { region in
mapView.region = region
// do other things with the region
}
So I've tried to recreate this for another method that I need to return an array of object type RunDetail:
func loadRuns(completion: ([RunDetail]) -> ()) {
// we need name, distance, time and user
databaseHandle = databaseRef.child("RunList").observe(.value, with: { (snapshot) in
self.count = Int(snapshot.childrenCount)
print(self.count!)
// more stuff happening here to add data into an object called RunDetail from firebase
// add RunDetail objects into array called 'run'
})
completion(runs)
}
I am not sure if I am setting this up correctly above^.
I still cannot get my head around getting the completion handler working (I really don't understand how to set it up). Can someone please help me and let me know if I am setting this up properly? Thanks.
You need to move the completion(region) to inside the Firebase completion block and add #escaping after completion:.
Also, you should not force unwrap optionals. It is easy enough to check that they are not nil and this will prevent the app from crashing.
func mapRegion(completion: #escaping (MKCoordinateRegion?) -> Void) {
let ref = Database.database().reference()
ref.child("RunList").child(runName).observe(.value, with: { (snapshot) in
guard
let runData = snapshot.value as? Dictionary<String,Double>,
let minLat = runData["startLat"],
let minLng = runData["startLong"],
let maxLat = runData["endLat"],
let maxLng = runData["endLong"]
else {
print("Error! - Incomplete Data")
completion(nil)
return
}
var region = MKCoordinateRegion()
region.center = CLLocationCoordinate2D(latitude: (minLat + maxLat) / 2, longitude: (minLng + maxLng) / 2)
region.span = MKCoordinateSpanMake((maxLat - minLat) * 1.1, (maxLng - minLng) * 1.1)
completion(region)
})
}
Then update your code to this.
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
mapRegion { (region) in
if let region = region {
self.mapView.setRegion(region, animated: true)
}
}
}
For your loadRuns
func loadRuns(completion: #escaping (Array<RunDetail>) -> Void) {
let ref = Database.database().reference()
ref.child("RunList").observe(.value, with: { (snapshot) in
var runs = Array<RunDetail>()
// Populate runs array.
completion(runs) // This line needs to be inside this closure.
})
}
This code does not add annotations to mapView. I saw in one answer that mapView function is called every time addAnotation is called so where's the problem? But when I move map they show up.
func addPlacesMarkers(location:CLLocation) {
self.communication.getJsonData(self.getPubsNearByCreator(location)) { (finalData, error) -> Void in
if error != nil {
print(error)
} else {
if let row: NSArray = finalData {
for var i = 0; i < row.count; i++ {
let lat = row[i]["lat"] as! String
let lng = row[i]["lng"] as! String
let title = row[i]["name"] as! String
let id = row[i]["id"] as! String
let point = CustomizedAnotation(id: Int(id)!, name: title)
point.title = title
point.coordinate.latitude = Double(lat)!
point.coordinate.longitude = Double(lng)!
let keyExists = self.places[Int(id)!] != nil
if keyExists == false {
self.places.updateValue(point, forKey: Int(id)!)
}
}
var finalPlaces :[MKPointAnnotation] = []
for place in self.places.values {
finalPlaces.append(place)
}
self.mView.addAnnotations(finalPlaces)
self.mView.showsPointsOfInterest = false
}
}
}
}
You can't modify the UI in a thread different from the main.
You should put your UI modification code inside a dispatch_async block like this:
dispatch_async(dispatch_get_main_queue()) {
//Your code that modify the UI
self.mView.addAnnotations(finalPlaces)
}