How to query multiple keys with Firebase GeoFire using Swift? - arrays

Question

I've got a GeoFire query that is bringing back user id's or keys. I'm getting back keys in sequence, but I'm getting several sequences. How can I get the last updated sequence?
#IBAction func friendsNearMeACTN(sender: AnyObject)
{
let geofireRef = self.ref.child("UserLocations")
let geoFire = GeoFire(firebaseRef: geofireRef)
let circleQuery = geoFire.queryAtLocation(self.location, withRadius: 20.6)
circleQuery.observeEventType(.KeyEntered, withBlock: { (key: String!, location: CLLocation!) in
self.localUsers.append(key)
self.getLocalUsers()
})
}
func getLocalUsers()
{
print(self.localUsers)
}
This is what I'm getting back from func getLocalUsers()....
["WGueYzDjH4NW2vneHOyGmjf6PYB3"]
["WGueYzDjH4NW2vneHOyGmjf6PYB3", "Cg4pQj36ttNUuWNqtc16tIFmI0A2"]
["WGueYzDjH4NW2vneHOyGmjf6PYB3", "Cg4pQj36ttNUuWNqtc16tIFmI0A2", "N5pgqGEhW2f7PGGVmB3AQ8v1uPk2"]
How can I simply get the last array?

Answer 1

The answer is that the GeoFire query is a continuous asynchronous call and needs the final code observeReadyWithBlock to feed the self.localUsers() the collected information only. Here is the example...
let regionQuery = geoFire.queryWithRegion(self.region)
regionQuery.observeEventType(.KeyEntered, withBlock: { (key: String!, location: CLLocation!) in
var users = [String]()
users.append(key)
for keys in users
{
let user = keys
allKeys.append(user)
}
self.localUsers = allKeys
self.getLocalUsers()
})
regionQuery.observeReadyWithBlock({ () -> Void in
self.getLocalUsers()
})

Answer 2

The problem here is that you are calling getLocalUsers func every time the observer block is fired. You are calling it for every single result. You need to count the results and add 1 to the count every time the observer block is executed. When your count reaches the result count, call the getLocalUsers function once instead of 3 times. Try the code below. I have not tested it.
#IBAction func friendsNearMeACTN(sender: AnyObject){
var i = 0//The counter
let geofireRef = self.ref.child("UserLocations")
let geoFire = GeoFire(firebaseRef: geofireRef)
let circleQuery = geoFire.queryAtLocation(self.location, withRadius: 20.6)
circleQuery.observeEventType(.KeyEntered, withBlock: { (key: String!, location: CLLocation!) in
self.localUsers.append(key)
i += 1//Add one to i every time observer fires
if i == self.key.count {//if counter (i) is equal to the keys returned call getLocalUsers func once
self.getLocalUsers()
}
})
}
func getLocalUsers(){
print(self.localUsers)
}