How to make Firebase play nice with TableView - ios

Question

I am struggling to get my head around Firebase Real-time Database and to have it playing nicely with Table View in my restaurant ordering app!
Before reading my code (please don't laugh), what I am hoping to get my TableView is able to do are
1) sort the requests by category (using value retrieved from the key "RequestItemCategory" which has Int value of 1, 2, 3)
2) add the new request to the tableview AND sort the requests again according to the category
3) remove completed food request from the tableview when the customer or employee tick "complete order" on another device which will trigger a change to the "RequestCompleted" key of the requested child on Firebase to "true")
The only things that I can achieve after hours of mucking around are
when app starts, the app loads the table and displays all the requests in the right order according to their category but even the requests that are tagged completed on the Firebase are still displayed.
new orders are added to the bottom of the list but not sort into a category.
What I tried
1) Tag .queryEqual(toValue: "false", childKey: "RequestCompleted") to try to filter out completed requests returns an empty table (not nil information)
2) I can use a button to clear the requestArray then calls retrieveRequest() again. This will refresh the table and all requests will be in the right order but I like to have it done automatically if possible. Also, this method will create another observer so I ended multiple identical orders added to the list...
3) using .value instead of .childAdded - returns nil and the app crashes - I think I need to use for loops but not sure how to do it.
Please help thanks!
Codes are:
Class object
class Request {
var name : String = ""
var requestItem : String = ""
var seat : String = ""
var requestCategory : String = ""
}
Cell.swift
import UIKit
class CustomCellTableViewCell: UITableViewCell {
#IBOutlet var requestText : UITextField!
#IBOutlet var nameText: UITextField!
#IBOutlet var seatNumberText: UITextField!
#IBOutlet var timerText: UITextField!
#IBOutlet var cellBackground : UIView!
#IBOutlet var cellCategoryView : UIView!
#IBOutlet var cellCategoryLabel : UILabel!
override func awakeFromNib() {
super.awakeFromNib()
// Initialization code
}
override func setSelected(_ selected: Bool, animated: Bool) {
super.setSelected(selected, animated: animated)
// Configure the view for the selected state
}
}
ViewController.swift
import UIKit
import Firebase
import SVProgressHUD
class MainPageViewController: UIViewController, UITableViewDelegate, UITableViewDataSource, UITextFieldDelegate {
#IBOutlet weak var requestTableView: UITableView!
var requestArray : [Request] = [Request]()
override func viewDidLoad() {
super.viewDidLoad()
requestTableView.delegate = self
requestTableView.dataSource = self
requestTableView.register(UINib(nibName: "CustomCellTableViewCell", bundle: nil), forCellReuseIdentifier: "customRequestCell")
configureTableView()
retrieveRequest()
// Do any additional setup after loading the view.
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "customRequestCell", for: indexPath) as! CustomCellTableViewCell
cell.nameText.text = requestArray[indexPath.row].name
cell.seatNumberText.text = requestArray[indexPath.row].seat
cell.requestText.text = requestArray[indexPath.row].requestItem
cell.cellCategoryLabel.text = requestArray [indexPath.row].requestCategory
if cell.cellCategoryLabel.text == "1" {
cell.cellBackground.backgroundColor = UIColor.init(red: 142/255, green: 0/255, blue: 0/255, alpha: 0.65)
} else if cell.cellCategoryLabel.text == "2" {
cell.cellBackground.backgroundColor = UIColor.init(red: 234/255, green: 179/255, blue: 0/255, alpha: 0.75)
} else {
cell.cellBackground.backgroundColor = UIColor.init(red: 0/255, green: 113/255, blue: 119/255, alpha: 0.65)
}
return cell
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return requestArray.count
}
func configureTableView() {
requestTableView.rowHeight = UITableView.automaticDimension
requestTableView.estimatedRowHeight = 73
}
func retrieveRequest() {
let ref = Database.database().reference().child(“Restaurant”).child("Requests").queryOrdered(byChild: "RequestItemCategory")**.queryEqual(toValue: "false", childKey: "RequestCompleted")** adding .queryEqual doesn't work...
ref.observe(.childAdded) { (snapshot) in
let snapshotValue = snapshot.value as? [String : AnyObject] ?? [:]
let customerName = snapshotValue["Lastname"]
let customerSeatnumber = snapshotValue[“Seat”]
let customerRequestedItem = snapshotValue["RequestItem"]
let customerRequestedItemCategory = snapshotValue ["RequestItemCategory"]
let request = Request()
request.name = customerName as! String
request.seat = customerSeatnumber as! String
request.requestItem = customerRequestedItem as! String
request.requestCategory = "\(customerRequestedItemCategory!)"
self.requestArray.append(request)
self.configureTableView()
self.requestTableView.reloadData()
}
}
}
ps. the requestLabel.text is used to change the color of a particular UIView according to the category (RequestItemCategory)