tableview in tabbar not reloading - ios

Question

I have a TabBar with various Tabs in my RestaurantApp, When I click the addToCart and goes to the CartViewContorller, the added item don't show I have to relaunch the App to see the item there. I have seen similar questions with various answer on this question here but non of the solutions seems to work in my case I don't really know whats wrong. Below is my code for the CartViewContorller I want to reload tableview anytime it is loaded. Thanks all for your help
import UIKit
import Alamofire
import os.log
class CartViewController: UITableViewController {
var cartData = [CartResponse.Cart]()
override func viewDidLoad() {
super.viewDidLoad()
cart()
tableView.delegate = self
tableView.dataSource = self
let nib = UINib(nibName: "viewCartCell", bundle: nil)
tableView.register(nib, forCellReuseIdentifier: "cartCustomCell")
let footerView = UIView()
footerView.backgroundColor = UIColor.red
footerView.frame = CGRect(x: 0, y: 0, width: view.frame.width, height: 60)
tableView.tableFooterView = footerView
}
override func viewDidAppear(_ animated: Bool) {
super.viewWillAppear(animated)
self.tableView.reloadData()
}
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return cartData.count
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
guard let cell: CartTableViewCell = self.tableView.dequeueReusableCell(withIdentifier: "cartCustomCell", for: indexPath) as? CartTableViewCell else {
os_log("Dequeue cell isn't an instance of CustomTableCell", log: .default, type: .debug)
fatalError()
}
cell.recipeNameLbl?.text = cartData[indexPath.row].recipeName
cell.restaurantNameLbl?.text = cartData[indexPath.row].restaurantName
cell.addtionalNoteLbl?.text = cartData[indexPath.row].additionalNote
cell.quantityLbl?.text = cartData[indexPath.row].recipeQuantity
cell.totalLbl?.text = cartData[indexPath.row].recipePrice
cell.totalCostLbl?.text = cartData[indexPath.row].totalCost
return cell
}
override func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
return 100
}
override func tableView(_ tableView: UITableView, commit editingStyle: UITableViewCellEditingStyle, forRowAt indexPath: IndexPath) {
guard editingStyle == .delete else {return}
//getting userId from defaults
let CartId = cartData[indexPath.row].cartId
let cartId = CartId
//creating parameters for the post request
let parameters: Parameters=[
"cartId":Int(cartId)
]
//Constant that holds the URL for web service
let URL_SELECT_FROM_CART = "http://localhost:8888/restaurant/deleteFromCart.php?"
Alamofire.request(URL_SELECT_FROM_CART, method: .post, parameters: parameters).responseJSON {
response in
//printing response
print(response)
}
cartData.remove(at: indexPath.row)
tableView.deleteRows(at: [indexPath], with: .automatic)
}
//Fetching from Cart Method
func cart(){
//getting userId from defaults
let defaultValues = UserDefaults.standard
let userId = defaultValues.string(forKey: "userid")
//creating parameters for the post request
let parameters: Parameters=[
"userId":Int(userId!)!
]
//Constant that holds the URL for web service
let URL_SELECT_FROM_CART = "http://localhost:8888/restaurant/cart.php?"
Alamofire.request(URL_SELECT_FROM_CART, method: .post, parameters: parameters).responseJSON {
(response) in
let result = response.data
do{
let decoder = JSONDecoder()
let downloadedCart = try decoder.decode(CartResponse.self, from: result!)
self.cartData = downloadedCart.cartItem
DispatchQueue.main.async {
self.tableView.reloadData()
}
}catch {
print(error)
}
}.resume()
}
}

Answer 1

You can use :
import UserNotifications
NotificationCenter.default.post(name: NSNotification.Name(rawValue: "loadCart"), object: nil)
see more in this answer

Answer 2

You have to call cart() this method in viewWillAppear instead of calling viewDidload
override func viewWillAppear(_ animated: Bool) {
self.cart()
}