arrays - 如何使用 Swift 使用 Firebase GeoFire 查询多个键？

Question

我有一个 GeoFire 查询可以返回用户 ID 或 keys。我按顺序返回 keys，但我得到了几个序列。如何获取最后更新的序列？

@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)

}

这就是我从 func getLocalUsers()....

返回的内容

["WGueYzDjH4NW2vneHOyGmjf6PYB3"]
["WGueYzDjH4NW2vneHOyGmjf6PYB3", "Cg4pQj36ttNUuWNqtc16tIFmI0A2"]
["WGueYzDjH4NW2vneHOyGmjf6PYB3", "Cg4pQj36ttNUuWNqtc16tIFmI0A2", "N5pgqGEhW2f7PGGVmB3AQ8v1uPk2"]

我怎样才能简单地获取最后一个数组？

Answer 1

答案是 GeoFire 查询是一个连续的异步调用，需要最终代码 observeReadyWithBlock 来将收集到的信息提供给 self.localUsers()。这是示例...

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()
        })