How to populate an object array using a Firebase Database - ios

Question

I'm unable to create a function which returns an array of Product objects from my Firebase database.
I attempted using a switch within the closure to set variables to their respective names, and then instantiate the object after all variables have been set. I tried to play around with the scope of the closure to try and access the "retrieved value". Below is a snapshot of my Firebase Database, my product object, and my function.
func createArray() -> [Product] {
var newArray = [Product]()
let ref = Database.database().reference()
var productName = String()
var productHealth = String()
var productPrice = 0
var productImage = String()
for bigIndex in 0..<7 {
for smallIndex in 0..<4{
ref.child("masterSheet/\(bigIndex)/\(smallIndex)").observeSingleEvent(of: .value) { (snapshot) in let retrievedValue = snapshot.value}
//I used to have a switch statement here that went like
//switch smallIndex{ case 0: productPrice = retrievedValue as! String }
}
let completeProduct = Product(productName: productName, productHealth: productHealth, productPrice: productPrice, productImage: productImage)
newArray.append(completeProduct)
}
return newArray
}
Product Object:
import Foundation
import UIKit
class Product {
var productName: String
var productHealth: String
var productPrice: Int
var productImage: String
init(productName: String, productHealth: String, productPrice: Int, productImage: String ){
self.productName = productName
self.productHealth = productHealth
self.productPrice = productPrice
self.productImage = productImage
}
}
My goal is to produce an array of all of the items in the Database.

Answer 1

You need to fetch the value from smallIndex and set it into modelClass Product like this:
func createArray() -> [Product] {
var newArray = [Product]()
let ref = Database.database().reference()
for bigIndex in 0..<7 {
for smallIndex in 0..<4{
ref.child("masterSheet/\(bigIndex)/\(smallIndex)").observeSingleEvent(of: .value) { (snapshot) in let retrievedValue = snapshot.value}
//I used to have a switch statement here that went like
//switch smallIndex{ case 0: productPrice = retrievedValue as! String
let singleProduct = Product()
singleProduct.productName = "fetch value from small index"
singleProduct.productPrice = retrievedValue
sigleProduct.productHealth = "fetch value from small index"
newArray.append(singleProduct)
}
}
}
return newArray
}

Answer 2

For anyone wondering, this is the solution that ended up working for me :)
var product: [Product] = []
ref = Database.database().reference()
databaseHandle = ref.child("masterSheet").observe(.value) { (snapshot) in
guard let rawData = snapshot.value as? [AnyObject] else { return }
for item in rawData {
guard let itemArray = item as? [AnyObject] else { continue }
var pro = Product()
if itemArray.count > 0 {
pro.productName = itemArray[0] as? String
}
if itemArray.count > 1 {
pro.productHealth = itemArray[1] as? String
}
if itemArray.count > 2 {
pro.productPrice = itemArray[2] as? Int
}
if itemArray.count > 3 {
pro.productImage = itemArray[3] as? String
}
// if you use dict, do like this:
//pro.productImage = itemArray["productImage"] as? String
//pro.productPrice = itemArray["productPrice"] as? Int
product.append(pro)
}
self.tableView.reloadData()
}