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firebase json反序列化swift

json-deserialization firebase-storage nsdictionary firebase-realtime-database swift

Stefan · 技术社区 · 7 年前

我需要在字典中输入JSON数据,然后将其附加到数组中。

此类不符合密钥的键值编码 k0ta3ytnxawxcfbzoeyajcr3yyyy1'

let room = rooms[indexPath.row]

if let dictionary = room.members {

    let user = User()

    user.setValuesForKeys(dictionary)

    liveCell.members.append(user)

}

以下是课程

class User: NSObject {
    var email: String?
    var name: String?
    var profileImageUrl: String?
}

房间

class Room: NSObject {
    var rid: String?
    var owner: String?
    var groupChatName: String?
    var groupChatDescription: String?
    var members: NSDictionary?
}

数据库中的房间对象

"rooms" : {
    "B7C7E469-945E-4327-9473-AAE34FCB9B41" : {
      "groupChatDescription" : "123ae",
      "groupChatName" : "Test123",
      "members" : {
        "K0tA3yTnxAWxCFBZoeyAjcr3yYy1" : {
          "email" : "S@gmail.com",
          "name" : "Steve",
          "profileImageUrl" : "https://firebasestorage.googleapis.com"
        }
      },
      "owner" : "Steve"
    }
},

我已经使用dictionary方法从数据库中检索用户,但我发现datasnapshots之间存在一些差异。

Optional({
    email = "S@gmail.com";
    name = Steve;
    profileImageUrl = 
"https://firebasestorage.googleapis.com";
})

此格式适用于词典

数据快照使用 print(room.members) :

Optional({
    K0tA3yTnxAWxCFBZoeyAjcr3yYy1 =     {
        email = "S@gmail.com";
        name = Steve;
        profileImageUrl = 
"https://firebasestorage.googleapis.com";
    };
})

这种格式不适用于字典,我相信这是因为键,但我不知道如何摆脱它,因为这本质上就是我如何分离成员数组中的每个成员。

有什么建议吗?

至于liveCell是什么,这里有一个屏幕截图可以很好地解释它。。。

这是一个liveCell,你可以看到数据在哪里匹配。黄色矩形是另一个uicollectionview,其中包含一组成员profileimages,其中每个配置文件图像都位于红方块内。

希望这能解决问题

2 回复 | 直到 7 年前

Jay 7 年前

给定与您类似的Firebase结构

  "rooms"
    "room_0"
      "groupChatName" : "Test123",
      "members"
        "user_0"
          "name" : "Barry"
        "user_1"
          "name" : "Maurice"
        "user_2"
          "name" : "Robin"

我们从RoomClass和UserClass开始。请注意,我让这些类完成了繁重的工作——它们拆下快照并存储其值。

class RoomClass {
    var key = ""
    var groupChatName = ""
    var membersArray = [UserClass]()

    init(snapshot: DataSnapshot) {
        let dict = snapshot.value as! [String: Any]
        let membersSnap = snapshot.childSnapshot(forPath: "members")
        let snapKey = snapshot.key
        let groupName = dict["groupChatName"] as! String

        self.key = snapKey
        self.groupChatName = groupName

        for member in membersSnap.children {
            let memberSnap = member as! DataSnapshot
            let user = UserClass(snapshot: memberSnap)
            self.membersArray.append(user)
        }
    }
}

class UserClass {
    var key = ""
    var name = ""

    init(snapshot: DataSnapshot) {
        let dict = snapshot.value as! [String: Any]
        let snapKey = snapshot.key
        let userName = dict["name"] as! String
        self.key = snapKey
        self.name = userName
    }
}

然后,我们定义存储房间的数组和填充它的代码

var roomsArray = [RoomClass]()

func doButton0Action() {
    let roomsRef = self.ref.child("rooms")
    roomsRef.observeSingleEvent(of: .value, with: { snapshot in

        for child in snapshot.children {
            let snap = child as! DataSnapshot
            let room = RoomClass(snapshot: snap)
            self.roomsArray.append(room)
        }

        //this just demonstrates the rooms and members are loaded
        for room in self.roomsArray {
            let groupChatName = room.groupChatName

            print(groupChatName)

            for user in room.membersArray {
                let userName = user.name
                print("  \(userName)")
            }
        }
    })
}

和输出

Test123
  Barry
  Maurice
  Robin

jlmurph 7 年前

奇怪的解决方案,但您不应该使用firebase强制转换到[String:AnyObject]。这对我来说也不管用,但是:

snapshot.value as? [String:Any]

已经奏效了。在定制用例(房间、汽车等的类)中,添加自定义类来解释快照的价值,这更多是开发人员的责任 snapshot.value