I have these codes when I use storyboard:
override func prepare (for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == ProfilePhotoViewController.identifier {
guard let username = usernameTextField.text, let email = emailTextField.text, let password = passwordTextField.text else { return }
let profilePhotoVC = segue.destination as! ProfilePhotoViewController
profilePhotoVC.email = email
profilePhotoVC.username = username
profilePhotoVC.password = password
}
}
How do I write these code if I don't use storyboard and write them programmatically in order to pass the info from current controller to ProfilePhotoViewController?
EDIT:
After doing research I understand that doing this programmatically is through delegate. However, I don't know how I can complete the code:
Need to pass username, email and password from SignUpController ---> profilePhotoViewController
in SignUpController:
protocol SignUpControllerDelegate {
func handleSignUp(//what should I write here?)
}
var delegate: SignUpControllerDelegate?
#objc func handleSignUp() {
//...other code..//
delegate?.handleSignUp(//??)
}
In ProfileViewController:
what should I write to receive the username, email and password info from SignUpController?
We can create a view controller with/without a NIB file.
With NIB, you use init(nibName: String?, bundle: Bundle?) method. In this case, view will be defined using Interface Builder.
// bundle = nil denote the main bundle
let viewController = MyViewController(nibName:"MyViewController", bundle: nil)
Also you can define a custom UIViewController subclass without a NIB file and implement loadView() method.
override func loadView() {
self.view = UIView(...)
}
After that, we need to add the view into the view hierarchy.
self.view.addSubview(viewController.view);
// or
self.present(viewController, animated: false, completion: nil)
// or if we have UINavigationController
self.navigationController?.pushViewController(viewController, animated: false)
Try like this
guard let username = usernameTextField.text, let email = emailTextField.text, let password = passwordTextField.text else { return }
let profileVC = ProfilePhotoViewController()
profileVC.email = email
Related
I'm learning swift from couple months and one thing I keep screwing up is passing data between ViewControllers. When I PO the path of the forward looking variable from within the prepareForSegue method, the value is intact. But when the new ViewController actually appears and I checked its value, it is nil at that point. if anyone could point me in the right direction I'd be very appreciative.
class LoginViewController: UIViewController {
var user_ID:String = ""
//this below is within another method activated by button
Auth.auth().signIn(withEmail: email, password: password) { (result, error) in
if error != nil {
print ("there was an error signing in")
print (error!.localizedDescription)
return
}
else {
//go to home screen
let userUID = result?.user.uid
print (userUID)
self.user_ID = userUID
self.performSegue(withIdentifier: "MainSegue", sender: self)
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
//this is the destination VC
let viewController = segue.destination as! ViewController
viewController.user_ID = self.user_ID
//NOTE: if I break here and PO viewConroller.user_ID the value is intact
let homeViewController = (self.storyboard?.instantiateViewController(withIdentifier: "MainVC"))! as! ViewController
//let mainViewController = ViewController()
//mainViewController.user_ID = userUID
self.present(homeViewController, animated: true, completion: nil)
}
class ViewController: UIViewController {
var persons = [Person]()
let db = Firestore.firestore()
var user_ID:String = ""
//NOTE: WHEN `viewdidload` runs value of user_ID is nil
Phillip in the comments above provided the solution. The present ViewController was the problem. The segue already does that. Thank you!!!
I want to pass data to the first viewController which is embeded in navigationController.
To access this navigation controller it has a storyBoardID, I arrive at instantiate navigationController but I can not pass him data,
Here is my code:
extension UINavigationController {
func dismissAndPresentNavigationController(from storyboard: UIStoryboard?, identifier: String) {
guard let navigationController = storyboard?.instantiateViewController(withIdentifier: identifier) as? UINavigationController else { return }
print("OK")
if let nav = navigationController.navigationController?.viewControllers.first as? ChatBotViewController{
print("OK2")
}
self.dismiss(animated: false, completion: nil)
self.present(navigationController, animated: true, completion: nil)
}
}
The identifier that I put in parameter is the storyBoardID of the navigation controller.
How to transmit data to the first controller of navigationcontroller?
SOLUTION:
extension UINavigationController {
func dismissAndPresentNavigationController(from storyboard: UIStoryboard?, identifier: String, with fittoBottle: FittoBottle) {
guard let navigationController = storyboard?.instantiateViewController(withIdentifier: identifier) as? UINavigationController else { return }
if let nav = navigationController.viewControllers.first as? ChatBotViewController{
nav.fittoBottle = fittoBottle
}
self.dismiss(animated: false, completion: nil)
self.present(navigationController, animated: true, completion: nil)
}
After instantiating the navigation controller from the storyboard, you will be able to access the root view controller via navigationController.viewControllers.first.
guard let navigationController = storyboard?.instantiateViewController(withIdentifier: identifier) as? UINavigationController else { return }
if let chatBotViewController = navigationController.viewControllers.first as? ChatBotViewController {
chatBotViewController.fittoBottle = fittoBottle
}
self.dismiss(animated: false, completion: nil)
self.present(navigationController, animated: true, completion: nil)
To communicate between view controllers in an iOS app, the best way is using protocol (delegate) or Notification. In you case, extending an UINavigationController doesn't sound a good idea, because you shouldn't relay on extension methods to instance view controller and then passing any data to it, and as an extension method, it's not the responsibility for an UINavigationController to take care about ChatBotViewController or any other instanced controllers.
For my suggestion, in anywhere you want to show the ChatBotViewController, in your storyboard, create a presenting modal segue to the ChatBotViewController (which is embedded in an UINavigationController), and use performSegue(withIdentifier:sender:) to initiate the navigation controller, and override prepare(for:sender:) to set the data you want to pass in your ChatBotViewController.
Here's some codes for explaining:
import UIKit
struct FittoBottle {
}
class ChatBotViewController: UIViewController {
var fittoBottle = FittoBottle()
}
class ViewController: UIViewController {
func showChatController() {
/*
If there is any controller is presented by this view controller
or one of its ancestors in the view controller hierarchy,
we will dismiss it first.
*/
if presentedViewController != nil {
dismiss(animated: true) {
self.showChatController()
}
return
}
// Data that will be sent to the new controller
let fittoBottle = FittoBottle()
// ChatBotViewControllerSegue is the segue identifier set in your storyboard.
performSegue(withIdentifier: "ChatBotViewControllerSegue", sender: fittoBottle)
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
super.prepare(for: segue, sender: sender)
guard let navigationController = segue.destination as? UINavigationController else {
return
}
guard let chatBotController = navigationController.viewControllers.first as? ChatBotViewController else {
return
}
// Get the data from sender, if not found, create it there.
// Or if you don't pass it through sender, you can specify it here.
let fittoBottle = sender as? FittoBottle ?? FittoBottle()
chatBotController.fittoBottle = fittoBottle
}
}
I would like to pass data from EditPostViewController to NewsfeedTableViewController using delegates, but func remove(mediaItem:_) is never called in the adopting class NewsfeedTableViewController. What am I doing wrong?
NewsfeedTableViewController: UITableViewController, EditPostViewControllerDelegate {
override func viewDidLoad() {
super.viewDidLoad()
//set ourselves as the delegate
let editPostVC = storyboard?.instantiateViewController(withIdentifier: "EditPostViewController") as! EditPostViewController
editPostVC.delegate = self
}
//remove the row so that we can load a new one with the updated data
func remove(mediaItem: Media) {
print("media is received heeeee")
// it does't print anything
}
}
extension NewsfeedTableViewController {
//when edit button is touched, send the corresponding Media to EditPostViewController
func editPost(cell: MediaTableViewCell) {
let editPostVC = storyboard?.instantiateViewController(withIdentifier: "EditPostViewController") as? EditPostViewController
guard let indexPath = tableView.indexPath(for: cell) else {
print("indexpath was not received")
return}
editPostVC?.currentUser = currentUser
editPostVC?.mediaReceived = cell.mediaObject
self.navigationController?.pushViewController(editPostVC!, animated: true)
}
protocol EditPostViewControllerDelegate: class {
func remove(mediaItem: Media)
}
class EditPostViewController: UITableViewController {
weak var delegate: EditPostViewControllerDelegate?
#IBAction func uploadDidTap(_ sender: Any) {
let mediaReceived = Media()
delegate?.remove(mediaItem: mediaReceived)
}
}
The objects instantiating in viewDidLoad(:) and on edit button click event are not the same objects. Make a variable
var editPostVC: EditPostViewController?
instantiate in in viewDidLoad(:) with delegate
editPostVC = storyboard?.instantiateViewController(withIdentifier: "EditPostViewController") as! EditPostViewController
editPostVC.delegate = self
and then present it on click event
navigationController?.pushViewController(editPostVC, animated: true)
or
present(editPostVC, animated: true, completion: nil)
you can pass data from presenter to presented VC before or after presenting the VC.
editPostVC.data = self.data
I suggest having a property in NewsfeedTableViewController
var editPostViewController: EditPostViewController?
and then assigning to that when you instantiate the EditPostViewController.
The idea is that it stops the class being autoreleased when NewsfeedTableViewController.viewDidLoad returns.
I have a collection view with some cells representing a contact (their data has a phone number and name) and I am trying to add the contact to the iPhone contacts. I have created a segue from a button called "add contact" that is inside the CollectionViewCell to a navigation controller, and set its identifier as "ADD_CONTACT".
In the storyboard, my segue has a navigation controller with no root view controller.
in prepareToSegue of the view controller that delegates my UICollectionView I wrote this code:
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == ADD_CONTACT {
let dest = segue.destination as! UINavigationController
if let cell = sender as? SBInstructionCell {
if cell.isContact {
let newContact = CNMutableContact()
if let phone = cell.instructionBean?.contactAttachment?.phoneNumber{
newContact.phoneNumbers.append(CNLabeledValue(label: "home", value: CNPhoneNumber(stringValue: phone)))
}
if let name = cell.instructionBean?.contactAttachment?.contactName {
newContact.givenName.append(name)
}
let contactVC = CNContactViewController(forNewContact: newContact)
contactVC.contactStore = CNContactStore()
contactVC.delegate = self
dest.setViewControllers([contactVC], animated: false)
}
}
}
}
this results with a black screen.
How can this be fixed? I want to see the CNContactViewController
Eventually I solved this in a different approach using Closures.
In my UICollectionViewCell
I added this var:
var closureForContact: (()->())? = nil
Now on my button's action in the same cell I have this func:
#IBAction func addContactTapped(_ sender: UIButton) {
if closureForContact != nil{
closureForContact!()
}
}
Which calls the function.
In my CollectionView in cell for item at index path, I set the closure like this:
cell.closureForContact = {
if cell.isContact {
let newContact = CNMutableContact()
if let phone = cell.instructionBean?.contactAttachment?.phoneNumber{
newContact.phoneNumbers.append(CNLabeledValue(label: "home", value: CNPhoneNumber(stringValue: phone)))
}
if let name = cell.instructionBean?.contactAttachment?.contactName {
newContact.givenName.append(name)
}
let contactVC = CNContactViewController(forNewContact: newContact)
contactVC.contactStore = CNContactStore()
contactVC.delegate = self
contactVC.allowsEditing = true
contactVC.allowsActions = true
if let nav = self.navigationController {
nav.navigationBar.isTranslucent = false
nav.pushViewController(contactVC, animated: true)
}
}
}
This worked perfectly. I learned that for navigating from a cell, it is best to use closures.
I have a managedObject that is being passed from 1 view controller to another the first pass works fine but when I try to pass the next object after the relationship has been set it doesn't send anything and comes back as either nil or if I try to use other methods comes back with a syntax error. The code I am using for the view controllers is as follows
View Controller 1, The first object set:
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if let identifier = segue.identifier {
switch identifier {
case "popOver":
if let VC = segue.destinationViewController as? ClassDeckNameViewController
{
if let ppc = VC.popoverPresentationController {
VC.modalPresentationStyle = UIModalPresentationStyle.Popover
ppc.permittedArrowDirections = UIPopoverArrowDirection.Any
ppc.delegate = self
}
VC.classSave = (sender as! ClassSelection)
}
default: break
}
}
}
#IBAction func buttonPriest(sender: AnyObject) {
let entity = NSEntityDescription.entityForName("ClassSelection", inManagedObjectContext: classMOC!)
let newObject = ClassSelection(entity: entity!,insertIntoManagedObjectContext: classMOC)
newObject.classname = "Priest"
var error: NSError?
if let err = error {
println(err)
} else {
classMOC?.save(&error)
self.performSegueWithIdentifier("popOver", sender: newObject)
}
}
This passes the object without problem to the second view controller but this is the one that won't pass any further to the final presenting controller offering the user the final selections for their "Deck":
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if segue.identifier == "showCardSelection" {
let detailVC: CardSelectionViewController = segue.destinationViewController as! CardSelectionViewController
detailVC.passedDeckObject = (sender as! Deck)
}
}
#IBAction func enterButton(sender: AnyObject) {
let entityDescription = NSEntityDescription.entityForName("Deck",inManagedObjectContext: managedObjectContext!)
let storeDeck = Deck(entity: entityDescription!,insertIntoManagedObjectContext: managedObjectContext)
storeDeck.deckname = usersDeckName.text
storeDeck.classSelected = classSave!
var error: NSError?
managedObjectContext?.save(&error)
if let err = error {
status.text = err.localizedFailureReason
} else {
usersDeckName.text = ""
status.text = "Deck Saved"
self.performSegueWithIdentifier("showCardSelection", sender: storeDeck)
}
}
I made passedDeckObject a variable of type Deck? in the final view controller to set the final relationship methods I know I am doing something wrong but I am unsure what! Any help with this would be amazing!
This looks to be a misconfiguration issue where the segue is being triggered directly in the storyboard rather than calling your code. As such the sender is a button rather than the new entity instance you're expecting.
To fix, disconnect the segue in the storyboard and connect (if it isn't already) the button to your action method in the view controller.