I am having a hard time updating an array in my app that controls a table. I want to be able to change a child node in Firebase Database and have it update on my users' end without me having to code and send an update. I need to be able to change their tag and have it update the table without the index being out of range.
Here is my Class Struct for the information for the users:
import UIKit
class User: NSObject {
var Name: String?
var Email: String?
var UID: String?
var Tag: String?
}
In my controller I have the following code to initialize the table with the info from Firebase:
func CreateDataArray() {
Database.database().reference().child("Users").observe(.childAdded, with: { (snapshot) in
if let dictionary = snapshot.value as? [String: AnyObject] {
let user = User()
//self.setValuesForKeys(dictionary)
user.Name = dictionary["Name"] as? String
user.Email = dictionary["Email"] as? String
user.UID = dictionary["UID"] as? String
user.Tag = dictionary["Tag"] as? String
if user.Tag == "Macro" {
self.macroUsersArray.append(user)
} else if user.Tag == "Micro" {
self.microUsersArray.append(user)
}
self.users.append(user)
self.userName.append(user.Name!)
self.filteredNames.append(user.Name!)
print(dictionary)
print(self.macroUsersArray)
DispatchQueue.main.async {
self.tableView.reloadData()
}
}
}, withCancel: nil)
}
I then have a function that listens for any changes from my Firebase and updates the arrays:
func updateDataArray() {
Database.database().reference().child("Users").observe(.childChanged, with: { (snapshot) in
if let dictionary = snapshot.value as? [String: AnyObject] {
let user = User()
//self.setValuesForKeys(dictionary)
user.Name = dictionary["Name"] as? String
user.Email = dictionary["Email"] as? String
user.UID = dictionary["UID"] as? String
user.Tag = dictionary["Tag"] as? String
if user.Tag == "Macro" {
self.microUsersArray.remove(at: 2)
} else if user.Tag == "Micro" {
self.macroUsersArray.remove(at: 2)
}
self.users.append(user)
self.userName.append(user.Name!)
self.filteredNames.append(user.Name!)
print(dictionary)
print(self.macroUsersArray)
DispatchQueue.main.async {
self.tableView.reloadData()
}
}
}, withCancel: nil)
}
I want to get the user that originally had the tag "macro" that got switch to "micro" to be removed from the macro list and show up in the micro list. I am not able to get the arrays to append and keep getting the indexPath is out of range error that crashes my app. I really need help and have been struggling with this the last few weeks.
Edit: I have decided to use observe.value so that when I make changes it reads it. Here is my code for creating the users' info:
func CreateDataArray() {
Database.database().reference().child("Users").observe(.value, with: { (snapshot) in
if let dictionary = snapshot.value as? [String: AnyObject] {
let user = User()
//self.setValuesForKeys(dictionary)
user.Name = dictionary["Name"] as? String
user.Email = dictionary["Email"] as? String
user.Tag = dictionary["Tag"] as? String
if user.Tag == "Macro" {
self.macroUsersArray.append(user)
} else if user.Tag == "Micro" {
self.microUsersArray.append(user)
}
self.users.append(user)
self.userName.append(user.Name!)
self.filteredNames.append(user.Name!)
print(dictionary)
print(self.macroUsersArray)
DispatchQueue.main.async {
self.tableView.reloadData()
}
}
}, withCancel: nil)
}
However, I am able to pull all the data into a snapshot but it is returning nil when I try to append. I am getting an error of nil on any line of code with "append(User.Name!)
I would love to figure out how to stop this nil and allow my observer to keep listening for changes in my database.
EDIT 2:
Here are my variables:
var allUsersArray = [User]()
var macroUsersArray = [User]()
var microUsersArray = [User]()
Here is my ViewDidLoad:
override func viewDidLoad() {
super.viewDidLoad()
updateDataArray()
}
Here is my updateDataArray code:
func updateDataArray() {
Database.database().reference().child("Users").observe(.childAdded, with: { (snapshot) in
if let dictionary = snapshot.value as? [String: AnyObject] {
let user = User()
//self.setValuesForKeys(dictionary)
user.Name = dictionary["Name"] as? String
user.Email = dictionary["Email"] as? String
user.UID = dictionary["UID"] as? String
user.Tag = dictionary["Tag"] as? String
self.allUsersArray.append(user)
self.users.append(user)
self.userName.append(user.Name!)
self.filteredNames.append(user.Name!)
self.macroUsersArray = self.allUsersArray.filter { $0.Tag == "Macro" }
self.microUsersArray = self.allUsersArray.filter { $0.Tag == "Micro" }
self.observeChangeInUserProperty()
DispatchQueue.main.async {
self.tableView.reloadData()
}
}
}, withCancel: nil)
}
Here is the observeChangeInUserProperty() function:
func observeChangeInUserProperty() {
let ref = Database.database().reference().child("Users").child("Talent")
ref.observe(.childChanged, with: { snapshot in
let key = snapshot.key
let tag = snapshot.childSnapshot(forPath: "Tag").value as! String // ! = never optional
//get the user from the allUsersArray by its key
if let user = self.allUsersArray.first(where: { $0.Tag == key }) {
if user.Tag != tag { //if the tag changed, handle it
user.Tag = tag //update the allUsersArray
if tag == "Macro" { //if the new tag is Macro remove the user from the Micro array
if let userIndex = self.microUsersArray.firstIndex(where: { $0.Tag == key }) {
self.microUsersArray.remove(at: userIndex)
self.macroUsersArray.append(user) //add user to macro array
}
} else { //new type is micro so remove from macro array
if let userIndex = self.macroUsersArray.firstIndex(where: { $0.Tag == key }) {
self.macroUsersArray.remove(at: userIndex)
self.microUsersArray.append(user)
}
}
//reload the tableviews to reflect the changes
self.microTableView.reloadData()
self.tableView.reloadData()
}
}
})
}
I am getting empty arrays for Macro and Micro. I don't know what I am doing wrong.
EDIT 3:
Here is my new user struct with initialization from Firebase:
import UIKit
import Firebase
class User: NSObject {
var Name: String?
var Email: String?
var UID: String?
var Tag: String?
init?(from snapshot: DataSnapshot) {
let dictionary = snapshot.value as? [String: Any]
self.Name = dictionary!["Name"] as? String
self.Email = dictionary!["Email"] as? String
self.UID = dictionary!["UID"] as? String
self.Tag = dictionary!["Tag"] as? String
}
}
I am now able to append the arrays but they are not populating my tables. I can also change the user's tag in Firebase without the app crashing but it doesn't observe the changed Tag and move the user to the other array. So I need help with those two things.
