So I was doing a test for another swift project and I wanted to connect a TableViewController that had a NavigationController embedded in to a regular ViewController using a segue between a bar button item and the second ViewController. When I control-drag the button to the ViewController, I only get the following options:
From what I understand, I should see a long list of items including show and show detail. Even if I connect them with push or any other segue, I can't select show or show detail as the type of segue if I select the segue. What am I doing wrong? I have not made modifications to ViewController.swift. Thanks!
The new adaptive segue choices, "show", "show detail", and "present modally", and "popover presentation" are only available if you're using size classes. This makes sense because there's no need for the segue to be adaptive if you're not using size classes.
来源：https://stackoverflow.com/questions/26747446/why-cant-i-use-the-show-segue-in-xcode-6-1