how to perform segue to a VC with Container - ios

Question

see this gif
when I choose the city Med , it passed to the TableVC not to the FirstVC (MainVC)
can I do that ? segue to the mainVC with the data passed through
the container (TableVC) ?
here what I did so far
MainVC
Empty
TableVC
import UIKit
class passedViewController: UITableViewController {
#IBOutlet weak var passcelltow: UITableViewCell!
#IBOutlet weak var passcell: UITableViewCell!
var passedCity1 = "اختر المدينة الاولى"
var passedCity2 = "اختر المدينة الثانية"
override func viewDidLoad() {
super .viewDidLoad()
passcell.textLabel?.text = passedCity1
passcelltow.textLabel?.text = passedCity2
}
}
Table 1 with data to pass to the TableVC
import UIKit
class city2ViewController: UIViewController , UITableViewDelegate , UITableViewDataSource{
#IBOutlet weak var tableView: UITableView!
var city2 = ["RUH" , "Med" , "Jed"]
override func viewDidLoad() {
super.viewDidLoad()
tableView.delegate = self
tableView.dataSource = self
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return city2.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = UITableViewCell()
print(indexPath.row)
cell.textLabel?.text = city2[indexPath.row]
return cell
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
performSegue(withIdentifier: "show", sender: city2[indexPath.row])
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
let passing = segue.destination as! passedViewController
passing.passedCity2 = sender as! String
}
}
Table 2 is the same ..
commend error
0 1 2 Could not cast value of type 'UIViewController' (0x107a10288) to
'table_view_test_pass.passedViewController' (0x105dbfdf8). (lldb)

Answer 1

You can pass data via segues or protocols. Since you are using segues i will show you a complete example and how to do it the right way in Swift 3. Using only two ViewControllers.
Create two UITextFields in the main "ViewController".
Create a new view controller of type UIViewController call it "MainTabelViewController" and add a tableView in it. Select content Dynamic prototypes Style Grouped and create 1 prototype cell and add a UILabel to it for the city name. "Don't forget the put the cell identifier name". I called it "cell".
Add the delegates and data sources to the class and add its functions like in code.
Create a segue from the main view controller to the main table view controller. And create another segue the opposite direction. "Don't forget the put the segue identifier names" I called them "toCity" & "toMain"
Create a "CityTableViewCell" controller of type UITableViewCell and create an IBOutlet of UILabel type where you will save the city name in as a text.
Edit this part in the AppDelegate.swift To delete the city names saved using in the UserDefaults every time the app is launched. So i wont populate the UITextFields randomly every time.
import UIKit
#UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {
var window: UIWindow?
var userDefaults: UserDefaults!
func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
// Override point for customization after application launch.
userDefaults = UserDefaults.standard
userDefaults.removeObject(forKey: "City One")
userDefaults.removeObject(forKey: "City Two")
return true
}
This is the ordinary main ViewController.swift where you have your UITextFields in. I distinguish which UITextField did the user click on using the tags. You need to add also the UITextFieldDelegate protocol to be able to use the the textFieldDidBeginEditing function. And i also save the selected city names using UserDefaults class to call them when user chooses the other city.
import UIKit
class ViewController: UIViewController, UITextFieldDelegate {
#IBOutlet var cityOneLabel: UITextField!
#IBOutlet var cityTwoLabel: UITextField!
#IBOutlet var continueButton: UIButton!
var selectedCityOne = ""
var selectedCityTwo = ""
var userDefaults: UserDefaults!
override func viewDidLoad() {
super.viewDidLoad()
cityOneLabel.delegate = self
cityTwoLabel.delegate = self
cityOneLabel.tag = 1
cityTwoLabel.tag = 2
continueButton.isEnabled = false
}
override func viewDidAppear(_ animated: Bool) {
userDefaults = UserDefaults.standard
cityOneLabel.text = selectedCityOne
cityTwoLabel.text = selectedCityTwo
if selectedCityOne != "" {
userDefaults.set(selectedCityOne, forKey: "City One")
} else {
cityOneLabel.text = userDefaults.string(forKey: "City One")
}
if selectedCityTwo != "" {
userDefaults.set(selectedCityTwo, forKey: "City Two")
} else {
cityTwoLabel.text = userDefaults.string(forKey: "City Two")
}
if cityOneLabel.text != "" && cityTwoLabel.text != "" {
continueButton.isEnabled = true
} else {
continueButton.isEnabled = false
}
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
#IBAction func continueButtonAction(_ sender: UIButton) {
//Later on continue after selecting the cities
}
func textFieldDidBeginEditing(_ textField: UITextField) {
performSegue(withIdentifier: "toCity", sender: textField.tag)
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "toCity" {
guard let cityVC = segue.destination as? MainTableViewController else {
return
}
cityVC.selectedTextField = sender as! Int
}
}
}
In the CityTabelViewCell.swift add the IBOutlet UILabel for the city name.
import UIKit
class CityTableViewCell: UITableViewCell {
#IBOutlet var cityNameLabel: 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
}
}
For the MainTabelViewController.swift write this:
Here is where i create an array of strings to populate my table view UILabels with.
import UIKit
class MainTableViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {
#IBOutlet var cityTabelView: UITableView!
var cityNamesArray = ["Cairo", "Alexandria", "Suez"]
var selectedTextField = Int()
var selectedCityName = ""
override func viewDidLoad() {
super.viewDidLoad()
cityTabelView.delegate = self
cityTabelView.dataSource = self
// Do any additional setup after loading the view.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath) as! CityTableViewCell
cell.cityNameLabel.text = cityNamesArray[indexPath.row]
return cell
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return cityNamesArray.count
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
selectedCityName = cityNamesArray[indexPath.row]
performSegue(withIdentifier: "toMain", sender: self)
}
func tableView(_ tableView: UITableView, titleForHeaderInSection section: Int) -> String? {
var title = ""
if selectedTextField == 1 {
title = "City One"
} else if selectedTextField == 2 {
title = "City Two"
}
return title
}
// MARK: - Navigation
// In a storyboard-based application, you will often want to do a little preparation before navigation
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "toMain" {
guard let mainVC = segue.destination as? ViewController else {
return
}
if selectedTextField == 1 {
mainVC.selectedCityOne = selectedCityName
} else if selectedTextField == 2 {
mainVC.selectedCityTwo = selectedCityName
}
}
}
}
This is how my layout looks like. Try it. I just added a continue button too if the user will have to go to another UIViewController after selecting the two cities.

Answer 2

If you want to segue to MainVC, you should instantiate a view controller from that class in prepare for segue.
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
let passing = segue.destination as! ViewController
passing.passedCity2 = sender as! String
}
Change ViewController to whatever the name of your class is for MainVC.

Answer 3

If you want to go back to the Parent View, you should be using an unwind-segue.
For that you must create the unwind segue method in the Parent View like this
#IBAction func unwindSegueFromChild(segue: UIStoryboardSegue){
// This code executes when returning to view
}
And in your child view you must create the unwind segue ctrl+dragging
There a dropdown appears and you select unwindSegueFromChild
Once you've done that, you must assign the unwind segue an identifier and programmatically perform it like a normal segue.