Question

我正在构建一个2阶应用程序，一个供客户发布订单，另一个供司机接受，所以从另一个应用程序我无法访问用户ID，它几乎没有工作，但是处理Firebase是一件令人头疼的问题，现在我试图在我的数据结构中添加/读取新订单，但无法在不创建大量循环来筛选数据的情况下读取新订单的方法，所以当我检测到数据的变化时，我会删除所有内容并再次加载所有数据，

这是我的代码

    override func viewDidLoad() {
    super.viewDidLoad()





    loadData()


    ref.observe(.childChanged, with: { snapshot in
        print("\n\n\nthe changed user is: \(snapshot.value)\n\n\n")
        self.usrData.removeAll() //if change is detected, remove     everything then readd them

        self.loadData() //load firebase Data to my data structure
    })

}

这是我的加载数据方法

 func loadData(){

    ref.observe(.childAdded, with: { snapshot in
        if let result = snapshot.children.allObjects as? [FIRDataSnapshot] {
            print("snapshot.value is snapshot \(snapshot.valueInExportFormat())")

            if let tes = snapshot.value as? Dictionary<String, AnyObject> {
                print("snapshot dictionarty is snapshot \(tes.reversed())")



                let est = tes.reversed()

                for t in est {
                    print("snapshot dictionarty name snapshot \(t.value["name"] as! String)")
                    print("snapshot dictionarty name snapshot \(t.value["email"] as! String)")
                    print("snapshot dictionarty name key \(t.key)")



                    let usr = userData(name: t.value["name"] as! String, email: t.value["email"] as! String, mobile: "", date: 0, latitude: "", longititude: "", ordertxt: "", status: "", usrKey:t.key, orderNumb:"")

                    self.usrData.append(usr)

                }

            }

            var count = 0


            for child in result {

                let  dict = child.childSnapshot(forPath: "orders").value as! Dictionary<String, AnyObject>
                print("dict is \(dict)")


                for dic in dict {

                    if  (dic.value["status"] as! String) == "pending" {

                        self.usrData[count].mobile = dic.value["mobile"] as! String
                        self.usrData[count].date = dic.value["date"] as! NSNumber
                        self.usrData[count].latitude = dic.value["latitude"] as! String
                        self.usrData[count].longititude = dic.value["longitude"] as! String
                        self.usrData[count].ordertxt = dic.value["orderText"] as! String
                        self.usrData[count].status = dic.value["status"] as! String
                        self.usrData[count].orderNumb = dic.key

                        print("\(count) dic key is\(dic.key)")

                    } else {
                        print("\n\n\n status isn't pending for some reason -> \(self.usrData[count].status)")
                        self.usrData.remove(at: count)
                        count-=1
                        continue
                    }

                }
                count += 1
            }
        } else {
            print("\n\n result is nil or something\n\n");
        }


        self.tableView.reloadData()

    })



}

无论如何要改进它？

Answer 1

你可以试试这个： -

users:{

  userID1 :{...// DATA

    ORDERS :{
       orderID1 : true,
       orderID2 : true,
       orderID3 : true
         }
       },
  userID1 :{...// DATA

    ORDERS :{
       orderID1 : true,
       orderID2 : true,
       orderID3 : true
         }
       },
  userID1 :{...// DATA

    ORDERS :{
       orderID1 : true,
       orderID2 : true,
       orderID3 : true
         }
       }  

  orderes_Placed :{

   orderID1 : {//order details},
   orderID2 : {//order details},

   }
}

您应该避免在NoSql数据结构中嵌套，并尝试尽可能地将其展平。当您浏览深度节点时，它会增加 带宽消耗

要收听添加到数据库节点的newData，只需在该节点启动一个侦听器（ .observe（.childAdded ..）。

FIRDatabase.database().reference().child("orders_Placed").observe(.childAdded, with: {(Snapshot) in


        print(Snapshot)   // Will print out every new order that is placed via your app.

    })

我可以改进我的Firebase结构吗？

1 个答案: