I have a segue that works fine when it is directly from a UIViewController to a UITableViewController, but when I embed the second view in a navigation controller, the segue no longer seems to work and I get unexpectedly found nil while unwrapping optional error. I don't believe I need to change the code. Should I rebuild the app somehow? I've read about errors in Xcode 6 beta (though I'm using 6.1) that cause the order in which a developer builds the app to have an effect.
Because destination of your segue is not as NavigationController. You must set the controller as NavagationController first.
Try this code
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject!) {
if (segue.identifier == "showItemSegue") {
let controller: Your_TableViewController = (segue.destinationViewController as UINavigationController).topViewController as Your_TableViewController
}
}
I hope this work
Related
I have two view controllers, LoginViewController and TermsAndPrivacyViewController.
On first view controller, there is a button that has IBAction, which opens TermsAndPrivacyViewController. On TermsAndPrivacyViewController I have web view, that loads url I am passing from LoginViewController. So, this is the code(Login view controller):
#IBAction func tosAction(_ sender: Any) {
if let vc = UIStoryboard(name: "Login", bundle: nil).instantiateViewController(withIdentifier: kTOSViewControllerIdentifier) as? TermsAndPrivacyViewController{
vc.url = URL(string: kTOSUrl)
self.navigationController?.pushViewController(vc, animated: true)
}
}
On TermsAndPrivacyViewController, I have this:
override func viewDidLoad() {
super.viewDidLoad()
webView.navigationDelegate = self
if let `url` = url {
webView.load(URLRequest(url: url))
webView.allowsBackForwardNavigationGestures = true
}
}
So, when I hit a button, app crashes SIGABRT message, and nothing else. Also, I don't get any crash report on Firebase Crashlytics (I have detached an app from a debugger first, and produced a crash).
Now, the strange part :/ ... If I put a breakpoint on a first line of tosAction() method, and go step by step (or just let it continue), everything works normally. No crash???
Am I missing something obvious here? What is the reason of crashing? Also, I tried to put Exception Breakpoint but nothing changes. I only get this:
and a console:
so, kinda no information about crash at all.
EDIT
Ok, now the even more strange part :) I just tried app on different phones.
App crashes on iPhone 6s+, iOS 12.1(16B5059d), but it works normally on iPhone 6, iOS 12.0 (16A366)
maybe you use library or framework that not supported by those device.
you must see the error
did you try this?
when the app crashing, in the console press cmd+F and search exception.
now you can see your error
hope to helpful.
Maybe you can use segue methods inside your LoginViewController.
#IBAction func tosAction(_ sender: Any) {
performSegue(withIdentifier: "GoToWeb", sender: nil)
}
}
And call prepareForSegue
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if (segue.identifier == "GoToWeb") {
let vc = segue.destination as! TermsAndPrivacyViewController
vc.url = "YOUR_URL"
}
And the code inside TermsAndPrivacyViewController don't change
Edit:
Maybe your not binding well your UIButton, can you verify in the right panel, in the section "Show the connection inspector" if your button is call only once.
To get further information on this type of crashes, open the Breakpoints menu (or press CMD+8), click the plus icon in the bottom left corner and press Exception Breakpoint.... Right click, then edit. Add an action of the type Debugger Command and enter the following:
Reproduce the crash again, this time the console will output a more useful error message.
I have a view controller with a name input text box in it. I want to be able to pull the name.text value from my main view controller, but I'm struggling with the code.
Sorry, I know there are similar questions, I am struggling to understand where I am going wrong though, here is my code:
func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if segue.identifier == "statsegue" {
let statVC = segue.destination as! SecondViewController
NameLabelMain.text = statVC.NameDisplayStat.text
//or try that if above doesn't work: detailsVC.passedString = recipes[indexPath?row]
}
}
This is on my main page, trying to pull the data from my second view.
Any thoughts or suggestions would be awesome.
Thanks
This is a common timing problem.
In prepareForSegue the view of the destination view controller is not loaded yet so all IBOutlets are not connected yet (aka not available).
You can only access data which is available right after initialization.
However generally you are passing data from the source controller to the destination controller rather than the other way round.
I am creating an application in which there are 6 view controller in storyboard. The thing is that data is shared between the default view controller and the first one ( say A and B) which i added. i am using the prepareforseque method for passing data. the problem started when i added two more view controller. lets say C and D i created two new swift files and changed the two view controller class name. i created a textbox and button in C and label in D. when i pressed the button, the value of the text field is not passing into the D view controller although i used the same methods and code which i used for A and B. do i have to do anything else when i want to pass data between two newly added view controller.
first viewcontroller in which when a button is pressed value 1 needed to be passed:
class PlaySelectMenu: UIViewController {
var value = Int()
#IBAction func twotofive(sender: AnyObject) {
value = 1
}
override func viewDidLoad() {
super.viewDidLoad()
}
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
let nextView : PlayGameView = segue.destinationViewController as! PlayGameView
nextView.x = value
}
}
the second view controller which receive the value and print it
import Foundation
import UIKit
class PlayGameView: UIViewController{
var x = Int()
override func viewDidLoad() {
super.viewDidLoad()
print(x)
}
}
here i have added both the view controller from the object library and not working with the default one which is present in storyboard by default. i dont know why these two viewcontroller are not working. please help.
Regards Dev
One solution would be to write the data out to NSUserDefaults and then read it back from NSUserDefaults in the other view controller. Probably not the proper or correct way to share data between two view controllers, but it's been a reliable work around for me.
Other than that, you'd need to share your code so that we can see what's occurring.
Can you post also the code in your controllers C & D. And also if you have copy/paste the code inside your first two controllers into the two others, are you sure that in your prepareForSegue method you have changed the name of the destination segue ?
Assuming you have created the segue in Storyboard:
All you need is to do is put all of needed updates in prepareForSegue because twotofive is called after prepareForSegue.
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
value = 1
let nextView : PlayGameView = segue.destinationViewController as! PlayGameView
nextView.x = value
}
Since you have connected your segue from button click to view controller, when you press button segue is automatically called. Instead of connecting segue from button to VC, connect VC to VC. Then in button click method at the last add below line:
#IBAction func twotofive(sender: AnyObject) {
value = 1
self.performSegueWithIdentifier("<Name of the segue identifier>", sender: self)
}
This will call your prepareForSegue. If you are calling more then one VC using segue from a VC then you can use segue.identifier to check which VC was called as below
override func prepareForSegue(segue: UIStoryboardSegue!, sender: AnyObject!) {
if segue.identifier == "CVC" {
}
I am trying to use the performSegueWithIndentifier function to to create a segue from one ViewController to the next. But, when I press the button with the UITApGestureRecognizer connected to it, the View shifts to the debugger panel.
Here is the error it is displaying:
ContaminateTargetViewController: has no segue with identifier 'showMasterChemistryViewController'
(I cut out the personal Info)
Here is the ViewControllers Class:
import Foundation
import UIKit
class ContaminateTargetViewController: UIViewController {
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if segue.identifier == "showMasterChemistryViewController" {
let chemistryMasterViewController = segue.destinationViewController as! ChemistryMasterViewController
}
}
#IBAction func showPlaylistDetail(sender: AnyObject) {
performSegueWithIdentifier("showMasterChemistryViewController", sender: sender)
}
}
I also previously had to manual segues from the 2 buttons I have on the ViewController and recently deleted them to switch over to the UITapGestureRecognizer for the convenience. I am wondering if I have an error in my code that I do not see or if previously deleting the manual segues from the View is causing this error. If the problem is rooting from the previously deleted manual segues please tell me how to fix this in your error. If the problem is rooting form the code, please leave the code I should add, delete, or substitute.
Any suggestions or input is greatly appreciated.
Thanks in advance.
This error is called when you do not have the requested segue connected to your view controller. Are you sure that you have the two view controllers connected via a segue named "showMasterChemistryViewController" on your storyboard?
I am new to programming in Swift and I having the hardest time trying to figure out how to connect a static table view with 6 cells to 6 separate dynamic prototype views.
From looking at previous responses, I know that I have to identify each segue ("showRestaurant") and I thought it would go in the override segue method but I am not sure. I am also unsure of how to properly code it.
Please let me know if you have any solutions
Thanks so much
Diamond
With a static tableView you can simply ctrl-drag from the tableViewCell to the destination viewController. Choose the type of the segue and give it an identifier (i.e. segueToVC1).
Repeat that for each tableViewCell which should be linked to a viewController.
Then in your custom tableView class file you override prepareForSegue to do additional setup, passing values to the destination viewController etc:
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if segue.identifier == "segueToVC1" {
// ...
}
}