将所有firebase用户的所有子节点值加载到collectionView

Question

我正在尝试从Firebase数据库中的所有用户获取所有相同的子值，并且遇到了一些问题。在我的特定用例中，我希望所有用户的所有“Planning”/“planning”子值都加载到collectionView中。我已经能够直接手动映射到子项“Planning”的值，但我不得不使用currentUser.uid，这当然只给了我当前登录用户的“规划”值（所以不是所有用户“规划” “价值观”。同样，我想在我的整个Firebase数据库中加载带有所有“Planning”值的collectionView。在此先感谢您的帮助......我已经坚持了一段时间！

//来自Firebase的JSON

{
  "users" : {
    "CmtuebwVrmOG3n4uSsIK1b4FsSN2" : {
      "Planning" : {
        "-Kl_xoIEXw1HqbL9-JDA" : {
          "addedBy" : "CmtuebwVrmOG3n4uSsIK1b4FsSN2",
          "planning" : "Napa Valley, CA, USA",
          "timestamp" : 1.49635932283732E9
        }
      },
      "name" : "Daniel Meier",
    },
    "TFN8NFSPfdMBJQ15iDhhRSRVUcV2" : {
      "Planning" : {
        "-KlW0Tw3ZMnTDvHgN-NM" : {
          "addedBy" : "TFN8NFSPfdMBJQ15iDhhRSRVUcV2",
          "planning" : "Patagonia",
          "timestamp" : 1.496276397864224E9
        },
        "-KlW0nqdABHlMa7Lj31X" : {
          "addedBy" : "TFN8NFSPfdMBJQ15iDhhRSRVUcV2",
          "planning" : "Cabo San Lucas, Baja California Sur, Mexico",
          "timestamp" : 1.496276483532304E9
        },
        "-KlW1sc4t-jUKqXxQpuf" : {
          "addedBy" : "TFN8NFSPfdMBJQ15iDhhRSRVUcV2",
          "planning" : "Vancouver, BC, Canada",
          "timestamp" : 1.496276765230323E9
        },
        "-KlW4aCDUXKBqnxKoU04" : {
          "addedBy" : "TFN8NFSPfdMBJQ15iDhhRSRVUcV2",
          "planning" : "Santiago, Santiago Metropolitan Region, Chile",
          "timestamp" : 1.496277476204581E9
        },
        "-KlW6BQpoO4wIWsTJcnC" : {
          "addedBy" : "TFN8NFSPfdMBJQ15iDhhRSRVUcV2",
          "planning" : "Istanbul, İstanbul, Turkey",
          "timestamp" : 1.496277894928425E9
        },
        "-KlWFHKBKrEd-z8qM9gz" : {
          "addedBy" : "TFN8NFSPfdMBJQ15iDhhRSRVUcV2",
          "planning" : "Lyon, France",
          "timestamp" : 1.496280278376963E9
        },
        "-Kl_wL42PfG_MtvkwWpk" : {
          "addedBy" : "TFN8NFSPfdMBJQ15iDhhRSRVUcV2",
          "planning" : "Kentucky, USA",
          "timestamp" : 1.496358936906602E9
        }
      },
      "name" : "Dan Meier",
    },
    "jtnJjBCW9mdkvXy7DV7ox1DUvzO2" : {
      "Planning" : {
        "-Kl_xgDG-7CpdQyvrbM5" : {
          "addedBy" : "jtnJjBCW9mdkvXy7DV7ox1DUvzO2",
          "planning" : "Hong Kong Island, Hong Kong",
          "timestamp" : 1.496359289751177E9
        },
        "-Kl_xi0vCO-BZ10AMua3" : {
          "addedBy" : "jtnJjBCW9mdkvXy7DV7ox1DUvzO2",
          "planning" : "London, UK",
          "timestamp" : 1.496359297153533E9
        }
      },
      "name" : "Daniel Meier",
    }
  }
}

// NSObject模态对象

class CurrentPlanner: SafeJsonObjectPlanner {

    var planningPlace: String?

    init(dictionary: [String: AnyObject]) {
        super.init()

        self.planningPlace = dictionary["planning"] as? String

        setValuesForKeys(dictionary)
    }
}

// baseCell CollectionViewCell类

class BaseCell: UICollectionViewCell {
    override init(frame: CGRect) {
        super.init(frame: frame)
        setupViews()
    }

    func setupViews() {

    }

    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }    
}

//用于从Firebase

获取计划值的功能

var plannedPlaces = [CurrentPlanner]()

   func fetchPlanningPlaces() {

        let baseRef = Database.database().reference().child("users")
        baseRef.observe(.childAdded, with: { (snapshot) in
            if let dictionary = snapshot.value as? [String: AnyObject] {
                let planningCell = CurrentPlanner(dictionary: dictionary)
                self.plannedPlaces.append(planningCell)
                print(self.plannedPlaces)
            }
        }, withCancel: nil)

        //this will crash because of background thread, so lets use dispatch_async to fix
        DispatchQueue.main.async(execute: {
            self.collectionView.reloadData()
        })
    }

// setup collectionView

 override func setupViews() {
        super.setupViews()

        fetchPlanningPlaces()

        // ...

        collectionView.register(BasePlanningCell.self, forCellWithReuseIdentifier: cellId)
    }

    func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
        return plannedPlaces.count
    }

    func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
        let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "cellId", for: indexPath) as! BasePlanningCell
        cell.currentPlanner = plannedPlaces[indexPath.item]
        return cell
    }