Transition Coordinator set too late to be useful for unwind segues

Number:rdar://17915792 Date Originated:05 August 2014
Status:Open Resolved:
Product:iOS SDK Product Version:iOS 8.0 (12A4345d)
Classification:Other Error Reproducible:Always
If you have a storyboard-driven unwind segue connected to an unwind IBAction there is no way to retrieve the transitionCoordinator for the unwind transition.

This would be beneficial to animate alongside the unwinding animation or execute code after the animation ended.

Steps to Reproduce:
1. Create an app that shows a modal VC and has a button to trigger an unwinding.
2. in the unwinding IBAction inspect the passed UIStoryboardSegue

Expected Results:
- the source and destination view controller's transitionCoordinator should be set to the instance of the transition coordinator for the unwinding segue

Actual Results:
- the source and destination view controller's transitionCoordinate is nil
- the same is also true als in canPerformUnwindSegueAction:
- there is no way to get hold of the relevant transitionCoordinator

This is the same on iOS 7. I believe that this is a general oversight since very few people understand unwind segues and instead keep using the dismissViewController methods programmatically.


Please note: Reports posted here will not necessarily be seen by Apple. All problems should be submitted at before they are posted here. Please only post information for Radars that you have filed yourself, and please do not include Apple confidential information in your posts. Thank you!