Why my table view disappears after scrolling to the bottom? - ios

Question

I don't know why my table view disappears after I reach the bottom of my table view.
here is the gif file of my problem: http://g.recordit.co/4hizPCyctM.gif
here is my code in my view controller
class CheckoutVC: UIViewController {
#IBOutlet weak var orderButton: DesignableButton!
#IBOutlet weak var tableView: UITableView!
#IBOutlet weak var floatingView: UIView!
#IBOutlet weak var totalPriceLabel: UILabel!
private let realm = RealmService.shared.realm
private var products = [Product]()
private var userOrder : Order?
private var productSelected : Product?
private var cartIsEmpty = false
override func viewDidLoad() {
super.viewDidLoad()
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
RealmService.shared.observerRealmErrors() { (error) in
self.showAlert(alertTitle: "Sorry", alertMessage: error?.localizedDescription ?? "", actionTitle: "OK")
}
userOrder = Order.getOrderFromRealmDatabase()
guard let userOrder = userOrder else {return}
products = Array(userOrder.products)
tableView.reloadData()
totalPriceLabel.text = "Total: \(userOrder.getTotalPriceFormattedWithSeparator())"
updateUI()
}
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(animated)
RealmService.shared.stopObservingErrors(in: self)
}
private func updateUI() {
guard let userOrder = userOrder else {return}
if userOrder.products.isEmpty {
tableView.isHidden = true
cartIsEmpty = true
orderButton.setTitle("Pilih Barang", for: .normal)
} else {
tableView.isHidden = false
cartIsEmpty = false
orderButton.setTitle("Pesan Barang", for: .normal)
}
}
}
//MARK: - Table View Delegate & Datasource
extension CheckoutVC : UITableViewDataSource {
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return userOrder?.products.count ?? 0
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
guard let cell = tableView.dequeueReusableCell(withIdentifier: CheckOutStoryboardData.TableViewIdentifiers.checkOutCell.rawValue, for: indexPath) as? CheckOutCell else {return UITableViewCell()}
guard let userOrderInRealm = userOrder else {return UITableViewCell()}
let products = userOrderInRealm.products
cell.productData = products[indexPath.row]
cell.indexPath = indexPath
cell.delegate = self
let stepperValue = Double(products[indexPath.row].quantity)
cell.stepperValue = stepperValue
return cell
}
}
and here is my code in the table view cell
class CheckOutCell: UITableViewCell {
var indexPath: IndexPath?
var delegate: CheckOutCellDelegate?
#IBOutlet weak var stepperGM: GMStepper!
#IBOutlet weak var productImageView: UIImageView!
#IBOutlet weak var productNameLabel: UILabel!
#IBOutlet weak var subCategoryNameLabel: UILabel!
#IBOutlet weak var pricePerUnitLabel: UILabel!
#IBOutlet weak var priceTotalPerItemLabel: UILabel!
var productData : Product? {
didSet {
updateUI()
}
}
var stepperValue : Double? {
didSet {
setStepper()
}
}
#IBAction func deleteButtonDidPressed(_ sender: Any) {
// send data to CheckoutVC
guard let indexPath = self.indexPath else {return}
self.delegate?.deleteButtonDidTapped(at: indexPath)
}
#IBAction func seeProductButtonDidPressed(_ sender: Any) {
// send data to CheckoutVC
guard let indexPath = self.indexPath else {return}
self.delegate?.viewProductButtonDidTapped(at: indexPath)
}
#IBAction func GMStepperDidTapped(_ sender: GMStepper) {
guard let indexPath = self.indexPath else {return}
let stepperValue = Int(sender.value)
self.delegate?.incrementOrDecrementButtonDidTapped(at: indexPath, counterValue: stepperValue)
}
func setStepper() {
guard let stepperValue = stepperValue else {return}
stepperGM.value = stepperValue
}
func updateUI() {
guard let productData = productData else {return}
// update UI
productNameLabel.text = productData.name
pricePerUnitLabel.text = productData.getFormattedUnitPriceWithSeparator()
priceTotalPerItemLabel.text = productData.getFormattedTotalPriceWithSeparator()
//set image
if let imagePath = productData.imagePaths.first {
guard let encodedImagePath = imagePath.addingPercentEncoding(withAllowedCharacters: CharacterSet.urlQueryAllowed) else {return}
guard let url = URL(string: encodedImagePath) else {return}
productImageView.kf.indicatorType = .activity //loading indicator
productImageView.kf.setImage(with: url, options: [.transition(.fade(0.2))])
}
}
}
and here is the code to get the data from realm database, I get the data from realm database synchronously.
static func getOrderFromRealmDatabase() -> Order {
let userID = "1"
let realmService = RealmService.shared.realm
let allOrder = realmService.objects(Order.self)
let theOrder = allOrder.filter("userID CONTAINS[cd] %#", userID).first
if let userOrder = theOrder {
return userOrder
} else {
// Order never setted up before in Realm database container
// then create Order in realm database
let newOrder = Order()
newOrder.userID = userID
newOrder.products = List<Product>()
RealmService.shared.save(object: newOrder)
return newOrder
}
}
what went wrong in here, I don't understand :(

Answer 1

Remove optional handling in numberOfRowsInSection because products count never 0. and tableview hidden code is never excuted.
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return userOrder?.products.count
}