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Right-clicking the Exit icon yields an empty window. Can't Ctrl-drag a connection to any IB elements or corresponding source files. Docs give no love. Doesn't appear in nib files, only storyboards. My assumption is that it's a corollary to segues, but I don't see any new methods to back it up. Anyone?

rsswtmr
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3 Answers3

222

I had a hard time following the accepted answer so here is more detail.

Given the photo below on view controller C you can "exit" back to any view controller in the segue path.

enter image description here

ViewController A you can write:

- (IBAction)done:(UIStoryboardSegue *)segue {
    // Optional place to read data from closing controller
}

ViewController B you can write:

- (IBAction)back:(UIStoryboardSegue *)segue {
    // Optional place to read data from closing controller
}

ViewController C you control drag from "back" button to the green exit option and select back: ViewController C you control drag from "done" button to the green exit option and select done: enter image description here

Note: Even though the methods are on other view controllers they show up for the ViewController C's exit. Control dragging and selecting a method defines which ViewController to unwind to.

Eric
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    One more note: sometimes green exit button not being active even all steps are done. In this case reopening storyboard (or xcode project) makes it work as expected. – zxcat Jul 27 '13 at 09:06
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    Another issue I had was that I didn't put my unwind segue method signature in my .h file or class extension. After I added it the unwind segue showed up in the popup. – Steve Moser Sep 06 '13 at 15:02
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    +Infinity for `Even though the methods are on other view controllers they show up for the ViewController C's exit.` – Andrew Nov 26 '14 at 22:36
104

There's a lot of information in the WWDC video "Session 407 - Adopting Storyboards in your App."

Say you have two view controllers linked by a segue. Implement the following exit action on the first view controller:

- (IBAction)done:(UIStoryboardSegue *)segue {
    NSLog(@"Popping back to this view controller!");
    // reset UI elements etc here
}

Then, on Storyboard scene for the second view controller, Ctrl-drag from a UI element, such as a button, to the exit icon at the bottom of this view controller. The done: action you added to the code of the first controller will appear as an option. Now, activating the button you Ctrl-dragged to the exit icon will pop back to the first view controller and maintain its original state (ie UI elements such as text input supposedly still intact).

Dmitry Minkovsky
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N S
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    It actually unwinds back to the exact same instance of the view controller (and its views). – Jon Hess Sep 25 '12 at 07:39
  • Thanks, I was reading this just to learn what the "Green Exit" was about, only to find out it resolve a problem for me. I had 2 view controllers separated by a TabBar controller and a navigation controller, and "Pop" didn't work to return backwards. This took 2 minutes and everything worked as you said! THANKS! – user589642 Dec 25 '12 at 20:26
  • How can I invoke action method on `Done` button in class of view B before exiting back to view A ? – expert Aug 30 '13 at 09:35
  • If you watch the WWDC video you can skip to 37:15 to see the part about "unwind segues" – moliveira Sep 02 '15 at 02:37
15

As addition to Eric answer here is how it works with :

The function you add to the destination controller looks like:

@IBAction func backFromOtherController(segue: UIStoryboardSegue) {
    NSLog("I'm back from other controller!")
}
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