I have a function that shows pins on a MKMapView based on the user's current location. This function utilizes GeoFire's GFQuery:
// Allows the user to scroll on the map and have the parties update
func mapView(_ mapView: MKMapView, regionWillChangeAnimated animated: Bool) {
let loc = CLLocation(latitude: mapView.centerCoordinate.latitude, longitude: mapView.centerCoordinate.longitude)
showPartiesOnMap(location: loc)
}
As you can see from the snippet of code, this function repeatedly calls showParties on map (for each time the location is updated). That function looks like this:
func showPartiesOnMap(location:CLLocation) {
circleQuery = geoFire?.query(at: location, withRadius: 2.5)
// Observe whenever we find a sighting. If there are 50 parties, this will be called 50 times
partyObserve = circleQuery?.observe(GFEventType.keyEntered, with: { (key, location) in
if let location = location, let key = key {
let anno: PartyAnnotation
self.fullPartyName = key
// Attempting to print just the name of the party and not the time
var characters = Array(key.characters)
var currentChar: Character = " "
var finalName: String = ""
var dateString: String = ""
var finalDate: Date? = nil
// Gets the name of the party
currentChar = characters.remove(at: 0)
while currentChar != "*" {
finalName += "\(currentChar)"
currentChar = characters.remove(at: 0)
}
// Gets the date the party was created
currentChar = characters.remove(at: 0)
while currentChar != "*" {
dateString += "\(currentChar)"
currentChar = characters.remove(at: 0)
}
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd HH:mm:ss Z"
finalDate = dateFormatter.date(from: dateString)!
// Check if the party should still exist
if(self.shouldBeDeleted(partyDate: finalDate!)) {
self.geoFire.removeKey(key)
}
else if characters.count > 0 {
// The party in question is public
}
else {
// Created an annotation because the party should not be deleted
anno = PartyAnnotation(coordinate: location.coordinate, partyName: finalName)
self.mapView.addAnnotation(anno)
}
}
})
}
The issue that I am facing is that when the user leaves this page, I am no longer able to properly observe anything on Firebase. For any future observes (non-GeoFire), I receive an unexpectedly found nil while unwrapping an optional value.
After a bunch of testing, I have concluded that the issue comes from the line:
partyObserve = circleQuery?.observe(GFEventType.keyEntered, with: { (key, location) in
If I comment this observation out, the problem does not happen. Unfortunately, I need this functionality so commenting it out is not a viable solution. I have attempted removingAllObservers and removing observes with Firebase Handles. Does anyone know why this may be happening or a possible solution?
Thanks in advance for the help!
