关于用户位置的GeoFire查询

Question

我对使用Firebase及其位置库GeoFire非常陌生。目前，我在构造数据时遇到了一些问题。

目前，我的数据库是这样的：

users
  facebook:xxxxx
    displayName: xx
    firstName: xx
    lastName: xx
    location:
      g: xxxx
      l:
        0: xxx
        1: xxx
  facebook:yyyyy
    displayName: yy
    firstName: yy
    lastName: yy
    location:
      g: yyyy
      l:
        0: yyy
        1: yyy

我想要查询的用户是接近我的当前用户登录。要做到这一点，我不明白我必须指定哪条路径。

目前我正在做这样的事情(但这不起作用)：

保存当前位置

let root = Firebase(url: "myapp.firebaseio.com")
let usersRoot = root.childByAppendingPath("users")
geoFire = GeoFire(firebaseRef: usersRoot.childByAppendingPath(root.authData.uid))

geoFire.setLocation(currentLocation, forKey: "location") { (error) in
   if (error != nil) {
      print("An error occured: \(error)")
   } else {
      print("Saved location successfully!")
   }
}

检索附近的其他用户

let geoFire = GeoFire(firebaseRef: Firebase(url: "myapp.firebaseio.com").childByAppendingPath("users"))
let query = geoFire.queryAtLocation(currentLocation, withRadius: radius)

query.observeEventType(GFEventTypeKeyEntered, withBlock: {
   (key: String!, location: CLLocation!) in

   print("+ + + + Key '\(key)' entered the search area and is at location '\(location)'")
   self.userCount++
   self.refreshUI()
})

更新

保存当前位置

let root = Firebase(url: "myapp.firebaseio.com")
geoFire = GeoFire(firebaseRef: root.childByAppendingPath("locations"))

geoFire.setLocation(currentLocation, forKey: root.authData.uid) { (error) in
   if (error != nil) {
      print("An error occured: \(error)")
   } else {
      print("Saved location successfully!")
   }
}

检索附近的其他用户

let geoFire = GeoFire(firebaseRef: Firebase(url: "myapp.firebaseio.com").childByAppendingPath("locations"))
let query = geoFire.queryAtLocation(currentLocation, withRadius: radius)

query.observeEventType(GFEventTypeKeyEntered, withBlock: {
   (key: String!, location: CLLocation!) in

   print("+ + + + Key '\(key)' entered the search area and is at location '\(location)'")
   self.userCount++
   self.refreshUI()
})

Answer 1

对于GeoFire，必须在树中保留一个仅包含地理位置的段，然后在树中有另一个段，其中包含有关项的其他信息。

user_locations
  uid1:
    g: xxxx
    l:
      0: xxx
      1: xxx
  uid2:
    g: xxxx
    l:
      0: xxx
      1: xxx
user_profiles:
  uid1:
    name: "giacavicchioli"
  uid2:
    name: "Frank van Puffelen"

另见：Query firebase data linked to GeoFire

Answer 2

若要保存与查询匹配的所有记录，必须使用以下内容存储所有记录：

    var allKeys = [String:CLLocation]()

    circleQuery.observeEventType(GFEventTypeKeyEntered, withBlock: {
        (key: String!, location: CLLocation!) in

        allKeys [key]=location
      }

然后使用

    circleQuery.observeReadyWithBlock({
        print("All initial data has been loaded and events have been fired!")
    })

Answer 3

在设置GFEventType时似乎存在问题。这将在下一个版本的GeoFire 1.3上得到解决，因为现在您可以这样做……

let geoFire = GeoFire(firebaseRef: ref)

var allKeys = [String:CLLocation]()

let query = geoFire.queryAtLocation(coordinates, withRadius: 0.2)
print("about to query")
query.observeEventType(GFEventType.init(0), withBlock: {(key: String!, location: CLLocation!) in
    print("Key: \(key), location \(location.coordinate.latitude)")
    allKeys [key] = location
})

你可以看到GFEventType.init(0)..。它映射到由于某些原因在Swift中没有正确映射到GeoFire上的三种枚举类型。