Swift: Pass multiple values between views - swift

I have a view that has two text fields and a button.
#IBOutlet var inputURL: UITextField!
#IBOutlet var inputName: UITextField!
#IBAction func submitUrlButton(sender: AnyObject) {
}
and a second view that has two variables:
var submittedURL = ""
var submittedName = ""
println("Name \(submittedName)")
println("URL \(submittedURL)")
In Swift How do I pass the values entered in the two text fields and assign them to those variables in the second view?
Thanks
EDIT FOR THETOM:
import UIKit
class ViewController: UIViewController {
#IBOutlet var inputURL: UITextField!
#IBAction func submitBtn(sender: AnyObject) {
performSegueWithIdentifier("submissionSegue", sender: self)
}
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject!) {
// Create a new variable to store the instance of the next view controller
let destinationVC = segue.destinationViewController as BrandsViewController
destinationVC.submittedURL.text = inputURL.text
}
}

You can use the method prepareForSegue.
In the first view (the one from which the segue is coming from) write the following code :
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject!) {
// Create a new variable to store the instance of the next view controller
let destinationVC = segue.destinationViewController as CustomViewController
destinationVC.submittedURL = inputURL.text
destinationVC.submittedName = inputName.text
}
Here CustomViewController is the custom class of the UIViewController to which the segue is going to.
To perform the segue programmatically in your button #IBAction do that :
#IBAction func buttonWasClicked(sender: AnyObject) {
performSegueWithIdentifier("submissionSegue", sender: self)
}

Since your view controllers are linked with segue you can override the prepareForSegue method in first view controller and pass data by doing so
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if (segue.identifier == "secondViewController") { // here secondViewController is your segue identifier
var secondViewController = segue.destinationViewController as SecondViewController // where SecondViewController is the name of your second view controller class
secondViewController.submittedURL = inputURL.text
secondViewController.submittedName = inputName.text
}
}
And to performSegue inside your button action use perfromSegueWithIdentifier method
#IBAction func submitUrlButton(sender: AnyObject) {
//replace identifier with your identifier from storyboard
self.performSegueWithIdentifier("secondViewController", sender: self)
}

The simplest way of accessing values globally not neccessary to pass with segue
First View controller
import UIKit
var submittedURL:NSString? // declare them here
var submittedName:NSString? // Now these two variables are accessible globally
class YourViewController : UIViewController
{
#IBOutlet var inputURL: UITextField!
#IBOutlet var inputName: UITextField!
#IBAction func submitUrlButton(sender: AnyObject) {
if inputURL.text == "" && inputName.text == ""
{
//Show an alert here etc
}
else {
self.submittedURL.text = inputURL.text
self.submittedName.text = inputName.text
}
}
}
SecondView Controller
import UIKit
class SecondviewController: UIViewController
{
//inside viewDidload
println(submittedURL)
println(submittedName)
}

Related

#IBOutlet property cannot have non-object type

I am trying to pass a struct between view controllers, but I get the compiler error "#IBOutlet property cannot have non-object type". I have tried to add #objc but still get the error. How can I pass this data between view controllers? Why do I get this error and how do I correct it? Thanks.
import UIKit
struct DocObject: Codable {
let filename: String
let doclink: Int
}
class ViewController: UIViewController {
#IBOutlet weak var textField: UITextField!
// var nameText = ""
var obj = DocObject(filename: "filename", doclink: 123)
override func viewDidLoad() {
super.viewDidLoad()
}
#IBAction func done(_ sender: Any) {
print ("In VC1 nameText ", obj)
performSegue(withIdentifier: "name", sender: self)
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
let vc = segue.destination as! VCTwo2
vc.finalObj = obj
}
}
import UIKit
class VCTwo2: UIViewController {
#IBOutlet var finalObj: DocObject!
// var finalName = 0
override func viewDidLoad() {
super.viewDidLoad()
print ("In VC2 ", finalObj!)
}
}
You only define a property with #IBoutlet if the property is loaded from a xib or storyboard. Since you are passing the data structure from another view controller just define finalObj as a regular var.
class VCTwo2: UIViewController {
var finalObj: DocObject!
override func viewDidLoad() {
super.viewDidLoad()
}
}

i cannot able to pass data between viewcontrollers via protocols

View controller A
class ViewController: UIViewController {
var delegate: server?
override func viewDidLoad() {
super.viewDidLoad()
}
#IBAction func ok(_ sender: Any) {
delegate?.datum(data: "sd")
performSegue(withIdentifier: "goingB", sender: self)
}
}
View controller B
protocol server {
func datum(data: String)
}
class ViewControllerB: UIViewController, server {
#IBOutlet weak var label: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
}
func datum(data: String) {
self.label.text = data
print(data)
}
}
I need to pass the data via view controllers but I cannot able to pass however I know we can pass data through protocols, but anyhow I end up with error when try to run the program
If you need to pass data from one view controller to another and you're using segue for presenting new view controller, you can just override prepare(for:sender:), there is no need to using delegates. Here you can get reference for controller which will be presented and you can assign its variable.
So, first create variable in second view controller and declare that if you assign it with new value, it changes text of your label
class ViewControllerB: UIViewController {
#IBOutlet weak var label: UILabel!
var variable: String? {
didSet {
label.text = variable
}
}
}
Now in first view controller override prepare(for:sender:) and if segue is segue which you've performed, downcast destination view controller and assign its variable
class ViewController: UIViewController {
#IBAction func ok(_ sender: Any) {
performSegue(withIdentifier: "goingB", sender: self)
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "goingB" {
let destinationVC = segue.destination as! ViewControllerB
destinationVC.variable = "sd"
}
}
}
Anyway, if you want to use your code with delegate, you have to set delegate of first view controller as second view controller which will be presented. For this purpose you can also use prepare(for:sender:) where you can get reference for destination of segue and then you can call your method on delegate
class ViewController: UIViewController {
var delegate: server?
#IBAction func ok(_ sender: Any) {
performSegue(withIdentifier: "goingB", sender: self)
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "goingB" {
let destinationVC = segue.destination as! ViewControllerB
delegate = destinationVC
delegate?.datum(data: "sd")
}
}
}
Notes:
Name protocol with big capital letter Server and we are talking about delegates, add delegate word: ServerDelegate
Constrain protocol for just for classes
Make then your delegate variable weak
protocol ServerDelegate: class {
func datum(data: String)
}
...
weak var delegate: ServerDelegate?
The simplest here is to to set the property directly in prepare.
However, if you want to use delegate, you can. Your problem is that you have mixed between A and B.
The way you wrote it, when you call delegate?.datum, delegate is not defined and we can't access datum.
What do you want to do ? Go from A to B, and when in B, update a label in B with data received from A.
Here just to show how to use (but clearly too complex compared with direct assignment).
protocol Server {
func datum() -> String
}
class ViewControllerB: UIViewController {
#IBOutlet weak var label: UILabel!
var delegate: Server?
override func viewDidLoad() {
super.viewDidLoad()
let data = delegate?.datum()
self.label.text = data
}
}
class ViewControllerA: UIViewController, Server {
override func viewDidLoad() {
super.viewDidLoad()
}
var data = "sd"
func datum() -> String {
return data
}
#IBAction func ok(_ sender: Any) {
performSegue(withIdentifier: "goingB", sender: self)
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if let destVC = segue.destination as? ViewControllerB {
destVC.delegate = self
}
}
}

Text field is permanently in the second view controller upon segue

I have been working on an app that allows multiple text fields from the first view controller pass over to the second view controller upon pressing a button. However, the text fields are permanently in the second view controller when I only want them to be if the button is pressed. Here is the code for the first view controller! Any help is greatly appreciated.
class ViewController: UIViewController {
#IBOutlet weak var textField: UITextField!
#IBOutlet weak var textField1: UITextField!
#IBAction func buttonTwo(_ sender: Any) {
if textField1.text != "" {
performSegue(withIdentifier: "segue", sender: self)
}
}
#IBAction func buttonOne(_ sender: Any) {
if textField.text != "" {
performSegue(withIdentifier: "segue", sender: self)
}
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
var secondController = segue.destination as! SecondViewController
secondController.myString1 = textField1.text!
secondController.myString = textField.text!
}
}
Here is the code in the second view controller:
class SecondViewController: UIViewController {
#IBOutlet weak var label: UILabel!
#IBOutlet weak var label1: UILabel!
var myString = String()
var myString1 = String()
override func viewDidLoad() {
super.viewDidLoad()
label.text = myString
label1.text = myString1
// Do any additional setup after loading the view.
}
}
Image of storyboard
This happens because, prepare for segue will be called every time you perform some segue action.
You should manage to have a bool variable that helps you track, if any button is clicked or not, if the segue is performed from the click of the button, then only you will have to set the text while preparing for segue.
here is your updated viewController
class ViewController: UIViewController {
#IBOutlet weak var textField: UITextField!
#IBOutlet weak var textField1: UITextField!
var isButtonClicked: Bool = false
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
/*reset isButtonClicked to false, when you back from second viewController */
isButtonClicked = false
}
#IBAction func buttonTwo(_ sender: Any) {
if textField1.text != "" {
isButtonClicked = true
performSegue(withIdentifier: "segue", sender: self)
}
}
#IBAction func buttonOne(_ sender: Any) {
if textField.text != "" {
isButtonClicked = true
performSegue(withIdentifier: "segue", sender: self)
}
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if isButtonClicked {
var secondController = segue.destination as! SecondViewController
secondController.myString1 = textField1.text!
secondController.myString = textField.text!
}
}
}
Try and share your results.

Delegate using Container View in Swift

I'm developing an app for iPad Pro. In this app, containerView use to add additional views and interact with them.
First, I created a protocol:
protocol DataViewDelegate {
func setTouch(touch: Bool)
}
Then, I created my first view controller
import UIKit
class ViewController: UIViewController, DataViewDelegate {
#IBOutlet var container: UIView!
#IBOutlet var labelText: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
}
func setTouch(touch: Bool) {
if touch == true {
labelText.text = "Touch!"
}
}
}
And finally, I created a view that will be embedded in containerView.
import UIKit
class ContainerViewController: UIViewController {
var dataViewDelegate: DataViewDelegate?
override func viewDidLoad() {
super.viewDidLoad()
}
#IBAction func touchMe(sender: AnyObject) {
dataViewDelegate?. setTouch(true)
}
}
But for some reason, nothing happened, the first view controller receives nothing in setTouch function.
My question is: In this case, using container, how can I make the communication between two ViewsControllers?
Like #nwales said you haven't yet set the delegate. You should do set the delegate in prepareForSegue function on your first viewController (who contain the viewContainer)
First select the embed segue and set an identifier in the attributes inspector.
Then in the parentViewController implement the func prepareForSegue like this:
Swift 4+:
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if (segue.identifier == "the identifier") {
let embedVC = segue.destination as! ViewController
embedVC.delegate = self
}
}
Below:
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
// Get the new view controller using segue.destinationViewController.
// Pass the selected object to the new view controller.
if (segue.identifier == "the identifier") {
let embedVC = segue.destinationViewController as! ContainerViewController
embedVC.dataViewDelegate = self
}
}
Looks like you defined the delegate, but have not set the delegate. This happens to me all the time.

Swift Take a Variable

I want to take a variable nomeLabel in the func goToSecondView and display it on a SecondView
class ViewController: UIViewController {
var nomeLabel:String!
#IBAction func goToSecondView(sender: AnyObject) {
self.performSegueWithIdentifier("goToSecondView", sender: self)
let newButton = sender as UIButton
nomeLabel = newButton.titleLabel!.text
println("nomeLabel \(nomeLabel)")
}
}
how can I do ?
You need to implement prepareForSegue where you have access to the destination view controller. Here is an example on how to do that:
class ViewController: UIViewController {
#IBOutlet var newButton: UIButton!
#IBAction func goToSecondView(sender: AnyObject) {
self.performSegueWithIdentifier("goToSecondView", sender: self)
}
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if segue.identifier == "goToSecondView" {
let secondViewController = segue.destinationViewController as SecondViewController
secondViewController.nomeLabel = self.newButton.titleLabel.text
}
}