Firebase在Swift中自动ID下检索数据 [英] Firebase retrieve data below auto ID In Swift

问题描述

从Firebase检索数据时遇到麻烦.

I'm in trouble in retrieving data from Firebase.

我想在自动ID下读取JSON中的所有contactName数据，然后追加到UIPickerView.

I'd like to read all contactName data in JSON under auto ID , then append to UIPickerView.

这是我的JSON树(使用childByAutoId())

Here is my JSON tree (used childByAutoId())

这是我的Swift代码

And Here is my Swift Code

dbRef = Database.database().reference()

dbRef.child("user").child("contacts").queryOrdered(byChild: "contactName").observeSingleEvent(of: .value, with: {(snapshot) in

    for snap in snapshot.children {

        let userSnap = snap as! DataSnapshot

        let contactName = userSnap.value as? String

            self.pickOption.append("\(contactName)")
        }
    })

但是结果显示了我所有的零数据……看起来像这样.

But the result shows me all nil data... looks like this.

我该如何解决..?

推荐答案

我解决了自己！

但是首先，我决定不使用UIPickerView.

But first of all, I decided not to use UIPickerView.

我想做的是在自动ID下添加数据.

And what I wanna do is to add data below auto ID.

我不确定这是否是解决此问题的好算法，但是无论如何，我做到了:)

I'm not sure this is good algorithm for solving this problem, But Anyway, I made it :)

dbRef.child("user/contacts/").observe(.value, with: {(snapshot) in

    if let result = snapshot.children.allObjects as? [DataSnapshot] {

            for child in result {

                let orderID = child.key as String //get autoID

                self.dbRef.child("user/contacts/\(orderID)/contactName").observe(.value, with: { (snapshot) in

                    if let nameDB = snapshot.value as? String {

                        if self.debtorName == nameDB {

                            self.dbRef.child("user/contacts/\(orderID)").updateChildValues(data)
                        }
                    }
                })
            }
        }
    })

这篇关于Firebase在Swift中自动ID下检索数据的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！