如何在Swift中观察下面的GeoFire句柄？

问题描述

这是Swift，Firebase和Geofire的问题。

我想知道如何在Swift中为下面的观察者删除一个GeoFire句柄。 >

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

以下工作正常（在viewDidDisappear中）：

  locationsEnd？.firebaseRef.removeAllObservers（）
  

然而，处理它不会：

  var locationHandle：UInt = 0 
 
重写func viewDidDisappear（_ animated：Bool）{
 super.viewDidDisappear（动画）
 
 //以下不起作用：
 locationsEnd？.firebaseRef.removeObserver（withHandle：locationHandle） （_ location：CLLocation）{
 
 locationHandle = locationsEnd！.query（at：location，withRadius：16.0）.observe（GFEventType。 init（rawValue：0）！，与：在
 
等等
））
} 
  

$ b $中的{（key，location） b

我已经尝试了locationHandle，如下所示，没有成功：

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

任何建议都会很好，正如前面提到的，我可以删除所有的观察者，但是在其他地方我需要删除一个句柄。

解决方案locationHandle在代码中被定义为一个UInt，它需要是一个FIRDatabaseHandle，所以

下面是一个移除Firebase句柄的例子

  var myPostHandle：FIRDatabaseHandle？ 
 $ b $ func someFunc（）
 {
 myPostHandle = ref.child（posts）。observeEventType（.childAdded，
 withBlock：{（snapshot） - >无效
 
让postBody = snapshot.value！[body] as！String 
 $ b $）
} 
 
 func stopObserving （）
 {
 if myPostHandle！= nil {
 ref.child（posts）。removeObserverWithHandle（myPostHandle）
} 
} 
  

对于GeoFire而言，更像是这样的



  let geoFire = GeoFire（firebaseRef：geofireRef）
 let center = CLLocation（纬度：37.7832889，经度：-122.4056973）
 var circleQuery = geoFire.queryAtLocation（center，withRadius：0.6）
 
 var queryHandle = circleQuery.observeEventType（.KeyEntered，$ b $ withBlock：{（key：String !, location：CLLocation！）in 
 //做某事
}）
  

然后删除，使用

  circleQuery.removeObserverWithFirebaseHandle（queryHandle）
  




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.

解决方案

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)

这篇关于如何在Swift中观察下面的GeoFire句柄？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！