Xcode 6 Storyboard Unwind Segue with Swift Not Connecting to Exit
When trying to connect a Navigation Bar Button to the Exit item of a ViewController in Xcode 6 (not really sure if it's an Xcode 6 problem but worth mentioning as it is in beta) it does not find the Swift function in the custom class.
The function it should be finding:
@IBAction func unwindToList(segue: UIStoryboardSegue) {
}
I made another button on the view just to make sure I could get an IBAction working with Swift and that I was writing it correctly. This works fine:
@IBAction func test(sender: AnyObject) {
NSLog("Test")
}
I have seen this question that seems like the same issue but according to the answers there this should be working.
Xcode 6 is in beta and, of course, Swift is very new, but wanted to see if anyone has come across this before considering it a potential bug.
This is a known issue with Xcode 6:
Unwind segue actions declared in Swift classes are not recognized by Interface Builder
In order to get around it you need to:
- Change
class MyViewController
to@objc(MyViewController) class MyViewController
-
Create an Objective-C header file with a category for MyViewController that redeclares the segue action.
@interface MyViewController (Workaround) - (IBAction)unwindToMyViewController: (UIStoryboardSegue *)segue; @end
In the storyboard, select the instance of MyViewController, clear its custom class, then set it back to MyViewController.
After these steps you are able to connect buttons to the exit item again.
Xcode 6 Release Notes PDF, Page 10
Instead of using the Objective-C workaround, Xcode 6 Beta 4, which can now be installed, supports the connection of unwind segues in the Interface Builder. You can update now from the iOS Dev center. Control-click and drag from the UI item you want to trigger the segue to the exit icon, and select the function unwindToSegue after having put the following code in the destination view controller.
@IBAction func unwindToSegue (segue : UIStoryboardSegue) {}
I was able to finally get it to work; the xcode6 IB is really fragile right now (crashes a lot too). I had to restart the IDE before I could connect the nav bar button item to the exit item. I ended up re-creating my test project and following the above suggestion (Xcode 6 Release Notes PDF, Page 10) to get it to work. In addition, when adding the .h file, I made sure to select my project target, which was unchecked by default. I also created my controller swift stub via the Cocoa Touch Class template (vs empty swift file). I used a modal segue in my nav controller.
ListTableViewController.h
#import <UIKit/UIKit.h>
@interface ListTableViewController
- (IBAction)unwindToList: (UIStoryboardSegue *)segue;
@end
ListTableViewController.swift
import UIKit
@objc(ListTableViewController) class ListTableViewController: UITableViewController {
@IBAction func unwindToList(s:UIStoryboardSegue) {
println("hello world");
}
}
hope that helps
In Xcode 6 Beta 4 which is available for download, unwind segues and interface builder is supported. I have tested it by myself in a little project.
In Swift 2.3 I found the external name of the parameter must be "withUnwindSegue":
@IBAction func unwindToThisView(withUnwindSegue unwindSegue: UIStoryboardSegue) {
...
}