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iosswiftfirebasegeofire

How to remove a GeoFire handle for the following observe in Swift?


This is a question for Swift, Firebase and Geofire.

I would like to know how to remove a GeoFire handle for the following observer in Swift.

locationsEnd!.query(at: location, withRadius: 16.0).observe(GFEventType.init(rawValue: 0)!, with: {(key, location) in

The following works fine (in viewDidDisappear):

locationsEnd?.firebaseRef.removeAllObservers()

However with handle it does not:

var locationHandle: UInt = 0

override func viewDidDisappear(_ animated: Bool) {
    super.viewDidDisappear(animated)

    //following does not work:
    locationsEnd?.firebaseRef.removeObserver(withHandle: locationHandle)
}

func aroundMe(_ location: CLLocation){

        locationHandle = locationsEnd!.query(at: location, withRadius: 16.0).observe(GFEventType.init(rawValue: 0)!, with: {(key, location) in

            //etc
        })
}

I've tried the locationHandle as follows, without success:

var locationHandle = FirebaseHandle()
var locationHandle: FirebaseHandle = 0
var locationHandle: UInt!
var locationHandle: UInt = 0
var locationHandle = FIRDatabaseHandle()
var locationHandle: FirebaseHandle = 0

Any suggestions would be great, as mentioned I can just remove all observers, but elsewhere I need to just remove a handle.


Solution

  • locationHandle is defined as an UInt in your code and it needs to be a FIRDatabaseHandle so

    Here's an example of removing a Firebase handle

    var myPostHandle : FIRDatabaseHandle?
    
    func someFunc()
    {
        myPostHandle = ref.child("posts").observeEventType(.childAdded,
          withBlock: { (snapshot) -> Void in
    
                let postBody = snapshot.value!["body"] as! String
    
        })
    }
    
    func stopObserving()
    {
        if myPostHandle != nil {
            ref.child("posts").removeObserverWithHandle(myPostHandle)
        }
    }
    

    For GeoFire it's more like this

    let geofireRef = FIRDatabase.database().reference()
    let geoFire = GeoFire(firebaseRef: geofireRef)
    let center = CLLocation(latitude: 37.7832889, longitude: -122.4056973)
    var circleQuery = geoFire.queryAtLocation(center, withRadius: 0.6)
    
    var queryHandle = circleQuery.observeEventType(.KeyEntered,
             withBlock: { (key: String!, location: CLLocation!) in
                 //do something
    })
    

    then to remove, use the

    circleQuery.removeObserverWithFirebaseHandle(queryHandle)