用户位置的 GeoFire 查询

Posted 2023-03-14

【中文标题】用户位置的 GeoFire 查询

【英文标题】：GeoFire query on User location

【发布时间】：2016-02-09 20:43:38

【问题描述】：

我对使用 Firebase 及其位置库 GeoFire 还是很陌生。目前，我在构建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

我想查询当前登录用户附近的用户。为此，我无法理解我必须指定什么路径。

目前我正在这样做（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()
)

【参考方案1】：

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

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

【讨论】：

谢谢！我现在正在尝试，但仍然无法正常工作。我试过这种方式（考虑到你的数据库结构）： let geoFire = GeoFire(firebaseRef: root.childByAppendingPath("user_locations")) let query = geoFire.queryAtLocation(currentLocation, withRadius: 10) query.observeEventType(GFEventTypeKeyEntered, withBlock: ( key: String!, location: CLLocation!) in print("+ + + + Key '(key)'进入搜索区域，在位置'(location)'") )

已解决，设置查询中心时出现问题。谢谢。

Firebase geofire-js：如何获取静态（固定）位置附近的键列表：***.com/questions/43632746/…

【参考方案2】：

要保存与查询匹配的所有记录，您必须使用以下方式存储所有记录：

    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!")
    )

【参考方案3】：

似乎在设置 GFEventType 时出现了问题。这将在下一个版本的 GeoFire 1.3 上得到解决，现在你可以这样做......

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
)

如您所见，GFEventType.init(0)... 映射到由于某种原因未正确映射到 Swift 中 GeoFire 的三种类型的枚举。