Prepare for Segue in Swift - ios

I'm facing the error message:
"UIStoryboardSegue does not have a member named 'identifier'"
Here's the code causing the error
if (segue.identifier == "Load View") {
// pass data to next view
}
On Obj-C it's fine using like this:
if ([segue.identifier isEqualToString:#"Load View"]) {
// pass data to next view
}
What am I doing wrong?

This seems to be due to a problem in the UITableViewController subclass template. It comes with a version of the prepareForSegue method that would require you to unwrap the segue.
Replace your current prepareForSegue function with:
override func prepareForSegue(segue: UIStoryboardSegue!, sender: AnyObject!) {
if (segue.identifier == "Load View") {
// pass data to next view
}
}
This version implicitly unwraps the parameters, so you should be fine.

Swift 4, Swift 3
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "MySegueId" {
if let nextViewController = segue.destination as? NextViewController {
nextViewController.valueOfxyz = "XYZ" //Or pass any values
nextViewController.valueOf123 = 123
}
}
}

I think the problem is you have to use the ! to unbundle identifier
I have
override func prepareForSegue(segue: UIStoryboardSegue?, sender: AnyObject?) {
if segue!.identifier == "Details" {
let viewController:ViewController = segue!.destinationViewController as ViewController
let indexPath = self.tableView.indexPathForSelectedRow()
viewController.pinCode = self.exams[indexPath.row]
}
}
My understanding is that without the ! you just get a true or false value

For Swift 2.3,swift3,and swift4:
Create a perform Segue at didSelectRowAtindexPath
For Ex:
self.performSegue(withIdentifier: "uiView", sender: self)
After that Create a prepareforSegue function to catch the Destination segue and pass the value:
Ex:
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "uiView"{
let destView = segue.destination as! WebViewController
let indexpath = self.newsTableView.indexPathForSelectedRow
let indexurl = tableDatalist[(indexpath?.row)!].link
destView.UrlRec = indexurl
//let url =
}
}
You need to create a variable named UrlRec in Destination ViewController

Swift 1.2
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject!) {
if (segue.identifier == "ShowDeal") {
if let viewController: DealLandingViewController = segue.destinationViewController as? DealLandingViewController {
viewController.dealEntry = deal
}
}
}

Prepare for Segue in Swift 4.2 and Swift 5.
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if (segue.identifier == "OrderVC") {
// pass data to next view
let viewController = segue.destination as? MyOrderDetailsVC
viewController!.OrderData = self.MyorderArray[selectedIndex]
}
}
How to Call segue On specific Event(Like Button Click etc):
performSegue(withIdentifier: "OrderVC", sender: self)

this is one of the ways you can use this function, it is when you want access a variable of another class and change the output based on that variable.
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
let something = segue.destination as! someViewController
something.aVariable = anotherVariable
}

Provided you aren't using the same destination view controller with different identifiers, the code can be more concise than the other solutions (and avoids the as! in some of the other answers):
override func prepare(for segue: NSStoryboardSegue, sender: Any?) {
if let myViewController = segue.destinationController as? MyViewController {
// Set up the VC
}
}

Change the segue identifier in the right panel in the section with an id. icon to match the string you used in your conditional.

override func prepareForSegue(segue: UIStoryboardSegue?, sender: AnyObject?) {
if(segue!.identifier){
var name = segue!.identifier;
if (name.compare("Load View") == 0){
}
}
}
You can't compare the the identifier with == you have to use the compare() method

Related

VC presenter is not being initialized prepare for segue IOS swift

Hello i am facing the problem as the prepare for segue function is not working properly i've the code can you please tell me how can i debug it as it has optional conditions how i can remove them and check what's the problem or what i am doing wrong as i just want a class to be initialized in target vc before the app navigates to other screen.
#IBAction func filterBtnPressed(_ sender: Any) {
self.performSegue(withIdentifier: "FilterSessionVC", sender: self)
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "FilterSessionVC", let navigation = segue.destination as? UINavigationController, let vc = navigation.topViewController as? FilterSessionVC {
vc.presenter = FilterSessionPresenterImplementation()
}
}
Basic debugging...
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
let identifier = segue.identifier
print("identifier:", identifier)
let dest = segue.destination
print("destination:", dest)
if let navigation = dest as? UINavigationController {
print("dest IS a UINavigationController")
if let vc = navigation.topViewController as? FilterSessionVC {
print("Top Controller IS a FilterSessionVC")
// here you can proceed
vc.presenter = FilterSessionPresenterImplementation()
} else {
print("Top Controller IS NOT a FilterSessionVC")
}
} else {
print("dest IS NOT a UINavigationController")
}
}
Set a breakpoint on the first line, then step through and inspect the results.

Finishing this snippet of code to pass data via a segue from one controller to another

I have a ViewController, "ViewController".
Within this view there is an attribute 'userEmailText.text' that I want to pass along to another view controller, "CreateNewCommunity"
I have a button connected to a segue with identifier 'createCommunitySegue'. I have create the code for when this is tapped:
#IBAction func createCommunityTapped(_ sender: AnyObject) {
self.performSegue(withIdentifier: "createCommunitySegue", sender: self)
}
In my second view controller, "CreateNewCommunity" I have a variable:
var myEmail: String?
and I have started to build the code ready to receive the data from the segue:
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "createCommunitySegue" {
let createCommunityController: CreateNewCommunity = segue.destination as! CreateNewCommunity
createCommunityController.myEmail =
}
}
How do I finish this set-up so that the initial 'userEmailText.text' value is passed by "ViewController" through segue 'createCommunitySegue' into "CreateNewCommunity" view controller?
Thanks
Why not just
createCommunityController.myEmail = userEmailText.text
I think your problem is that you have a wrong idea of how to pass data from one vc to another.
The VC that you are passing data to doesn't recieve the data. It is the VC that has the data proactively pass the data to the VC that needs it.
My guess would be that you put this code
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "createCommunitySegue" {
let createCommunityController: CreateNewCommunity = segue.destination as! CreateNewCommunity
createCommunityController.myEmail =
}
}
in the CreateNewCommunity controller! You should instead put the above in ViewController not CreateNewCommunity , and write
createCommunityController.myEmail = userEmailText.text
it should work.
VC1
#IBAction func createCommunityTapped(_ sender: AnyObject) {
self.performSegue(withIdentifier: "createCommunitySegue", sender: self)
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "createCommunitySegue" {
let createCommunityController: CreateNewCommunity = segue.destination as! CreateNewCommunity
createCommunityController.myEmail = userEmailText.text
}
}
VC2
var myEmail: String?
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
print(myEmail)
}

can't set prepare for segue in iOS

I have two controllers with UINavigationController (UIViewController(root) and UITableViewController). I need to click action at UIViewController and print something when move to UITableViewController
TableViewController.swift
func printString() {
print("hello world")
}
ViewController.swift
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if segue.identifier == "sendData" {
let navController = segue.destinationViewController as! UINavigationController
let controller = navController.topViewController as! TableViewController
controller.printString()
}
}
And after click I see that
Could not cast value of type 'myProjectName.TableViewController' (0x5a068) to 'UINavigationController' (0x17ffed4).
Why is that happening?
What about just:
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if segue.identifier == "sendData",
let controller = segue.destinationViewController as? TableViewController {
controller.printString()
}
}
}
It looks like the destinationViewController is the TableViewController.

Passing object with prepareForSegue Swift

I am trying to pass an object to another scene with prepareForSegue()
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
// Get the new view controller using [segue destinationViewController].
var nextScene = segue.destinationViewController as! VehicleDetailsTableViewController
// Pass the selected object to the new view controller.
if let indexPath = self.tableView.indexPathForSelectedRow() {
let selectedVehicle = vehicles[indexPath.row]
nextScene.currentVehicle = selectedVehicle
}
}
And I have currentVehicle object to catch these object. But, when I try to run, it brokes and get error about downcasting.
Error EDIT
Could not cast value of type 'XXX.DisplayViewController'
(0x1082dcd80) to 'XXX.VehicleDetailsTableViewController'
(0x1082dc9a0). (lldb)
You have to give the segue an identifier in the storyboard.(say mySegue)
Using Xcode 10 swift 4.x(Also works with Xcode 9 & 8 , swift 3.x)
override func prepare(for segue: UIStoryboardSegue, sender: Any?){}
Is called for all segues being called from your current UIViewController. So the identifier is to differentiate the different segues
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "mySegue" ,
let nextScene = segue.destination as? VehicleDetailsTableViewController ,
let indexPath = self.tableView.indexPathForSelectedRow {
let selectedVehicle = vehicles[indexPath.row]
nextScene.currentVehicle = selectedVehicle
}
}
If you are using Using Xcode 7, swift 2.x
Then use this code:
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if segue.identifier == "mySegue" {
var nextScene = segue.destinationViewController as! VehicleDetailsTableViewController
// Pass the selected object to the new view controller.
if let indexPath = self.tableView.indexPathForSelectedRow {
let selectedVehicle = vehicles[indexPath.row]
nextScene.currentVehicle = selectedVehicle
}
}
}
Place a breakpoint after nextScene and see if it is being triggered by clicking any cell in the TableView. If it isn't then the identifier name u provided in the storyboard must be different then the one given here.
In swift 3.0 Xcode 8 beta 6
AnyObject has been renamed to Any?
override func prepare(for segue: UIStoryboardSegue, sender: Any?){
let nextScene = segue.destinationViewController as! VehicleDetailsTableViewController
// Pass the selected object to the new view controller.
if let indexPath = self.tableView.indexPathForSelectedRow {
let selectedVehicle = vehicles[indexPath.row]
nextScene.currentVehicle = selectedVehicle
}
}
}
In Swift 3, Xcode 8
Just don't use "identifier". I don't know why but "segue.identifier" is always nil. I just used prepare method like this and works!
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if let secondController = segue.destination as? SecondController {
secondController.anyItemInSecondController = self.anyItemInFirstController
}
What that error is telling you is that segue.destinationViewController isn't a VehicleDetailsTableViewController. We don't have enough details to tell you why.
Check your segues and make sure they're all pointing to the correct place, and always check the identifier of your segue before you perform a cast.
if segue.identifier == "theNameOfYourSegue" // then do your cast

Swift Segue not working

I have a school project to make a swift app. I'm very new to swift and trying to pass data through the segue from a tableview to another view.
Here is the project file Download Here.
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if segue.identifier == "PopularDetails" {
let detailsViewController = segue.destinationViewController as DetailsViewController
let selectedIndexPath = popularTableView.indexPathForSelectedRow()
detailsViewController.shots = shots[selectedIndexPath.row]
}
}
}
.indexPathForSelectedRow() returns an optional. You have to unwrap it, before you can access its properties. Try:
let selectedIndexPath = popularTableView.indexPathForSelectedRow()
detailsViewController.shots = shots[selectedIndexPath!.row]
(see the exclamationmark)
Although #gutenmorgenuhu is correct, it's probably better practice to use:
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if segue.identifier == "PopularDetails" {
if let detailsViewController = segue.destinationViewController as? DetailsViewController {
if let selectedIndexPath = popularTableView.indexPathForSelectedRow() {
detailsViewController.shots = shots[selectedIndexPath.row]
}
}
}
}

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