Is there any better way to send information to child view? - swift

Question

I have a view controller which has a child view. I want to convey information from the view to the child view. To do so, I did this :
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
performSegue(withIdentifier: "visualize", sender: self)
invoiceNumber = indexPath.row
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
let vc = segue.destination as! PreviewViewController
vc.invoiceNumber = invoiceNumber
}
But the problem is that the value of invoiceNumber is not updated on the first iteration but on the second. I tried to see what the problem was and found that "invoiceNumber = indexPath.row" runs after "vc.invoiceNumber = invoiceNumber". Please help ! Thanks
Here is the code of printing :
import UIKit
class ViewController: UIViewController {
var invoiceNumber: Int = 0
override func viewDidLoad() {
super.viewDidLoad()
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
print(invoiceNumber)
}
}
Sorry I have mistaken :
var customerData: [[customerInformation]] = []
var itemsData: [[Item]] = []
var totalData: [TotalInformation] = []
var invoiceNumber = 0
override func viewDidLoad() {
super.viewDidLoad()
tableView.reloadData()
}
override func viewDidAppear(_ animated: Bool) {
let tabBar = tabBarController as! baseTabBarController
customerData = tabBar.customerData
itemsData = tabBar.itemsData
totalData = tabBar.totalData
tableView.reloadData()
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return customerData.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let invoiceCell = tableView.dequeueReusableCell(withIdentifier: "invoice", for: indexPath) as! invoiceTableViewCell
invoiceCell.textLabel?.text = (customerData[indexPath.row][0]).input
invoiceCell.detailTextLabel?.text = "Invoice n°" + String(indexPath.row)
invoiceCell.totalLabel.text = (totalData[indexPath.row]).total
return invoiceCell
}
func tableView(_ tableView: UITableView, commit editingStyle: UITableViewCell.EditingStyle, forRowAt indexPath: IndexPath) {
if editingStyle == .delete {
let tabBar = tabBarController as! baseTabBarController
tabBar.customerData.remove(at: indexPath.row)
//itemData.remove(at: indexPath.row)
tabBar.totalData.remove(at: indexPath.row)
customerData = tabBar.customerData
itemsData = tabBar.itemsData
totalData = tabBar.totalData
tableView.deleteRows(at: [indexPath], with: .fade)
}
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
invoiceNumber = indexPath.row
print(invoiceNumber, "yes")
performSegue(withIdentifier: "visualize", sender: self)
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
let vc = segue.destination as! PreviewViewController
vc.invoiceNumber = invoiceNumber
}
}
It is the "vc.invoiceNumber = invoiceNumber" which comes before the "invoiceNumber = indexPath.row" as I tried to change the value of invoiceNumber a variable in the view and print out the value in the child view and if showed its value first (I tested -1).
I added the Preview view controller which receives the invoiceNumber :
import UIKit
import WebKit
class PreviewViewController: UIViewController {
#IBOutlet var webPreview: UIWebView!
var invoiceComposer: InvoiceComposer!
var HTMLContent: String!
var invoiceNumber: Int = -1
override func viewDidLoad() {
super.viewDidLoad()
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
print(invoiceNumber)
createInvoiceAsHTML()
}
func createInvoiceAsHTML() {
invoiceComposer = InvoiceComposer()
if let tabBar = tabBarController as? baseTabBarController {
if let invoiceHTML = invoiceComposer.renderInvoice(invoiceNumber: String(invoiceNumber), invoiceDate: "", recipientInfo: tabBar.customerData[invoiceNumber][0].input, items: tabBar.itemsData[invoiceNumber], totalAmount: tabBar.totalData[invoiceNumber].total) {
webPreview.loadHTMLString(invoiceHTML, baseURL: NSURL(string: invoiceComposer.pathToInvoiceHTMLTemplate!)! as URL)
HTMLContent = invoiceHTML
}
}
else {
print("tabBarController is not of type baseTabBarController or either nil ")
}
}
}

Answer 1

Change the order of execution, like this:
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
invoiceNumber = indexPath.row
performSegue(withIdentifier: "visualize", sender: self)
}

Answer 2

I should have connected the segue from the view controller to the child view and not from the cell to the child view.