prepareForSegue方法有效，但它依赖于segue标识符魔术字符串。也许有更好的办法。

如果你知道你要找的VC的类，你可以用一个计算属性很好地做到这一点:

var camperVan: CamperVanViewController? {
  return childViewControllers.flatMap({ $0 as? CamperVanViewController }).first
  // This works because `flatMap` removes nils
}

这依赖于childViewControllers。虽然我同意依赖第一个类可能很脆弱，但命名您所寻找的类会使这个类看起来相当可靠。

如果有人正在寻找Swift 3.0，

viewController1, viewController2等等都是可访问的。

let viewController1 : OneViewController!
let viewController2 : TwoViewController!

// Safety handling of optional String
if let identifier: String = segue.identifier {

    switch identifier {

    case "segueName1":
        viewController1 = segue.destination as! OneViewController
        break

    case "segueName2":
        viewController2 = segue.destination as! TwoViewController
        break

    // ... More cases can be inserted here ...

    default:
        // A new segue is added in the storyboard but not yet including in this switch
        print("A case missing for segue identifier: \(identifier)")
        break
    }

} else {
    // Either the segue or the identifier is inaccessible 
    print("WARNING: identifier in segue is not accessible")
}

你可以这样写

- (IBAction)showDetail:(UIButton *)sender {  
            DetailViewController *detailVc = [self.childViewControllers firstObject];  
        detailVc.lable.text = sender.titleLabel.text;  
    }  
}

使用generic，你可以做一些甜蜜的事情。下面是Array的扩展:

extension Array {
    func firstMatchingType<Type>() -> Type? {
        return first(where: { $0 is Type }) as? Type
    }
}

你可以在你的viewController中这样做:

var viewControllerInContainer: YourViewControllerClass? {
    return childViewControllers.firstMatchingType()!
}

prepareForSegue方法有效，但它依赖于segue标识符魔术字符串。也许有更好的办法。

如果你知道你要找的VC的类，你可以用一个计算属性很好地做到这一点:

var camperVan: CamperVanViewController? {
  return childViewControllers.flatMap({ $0 as? CamperVanViewController }).first
  // This works because `flatMap` removes nils
}

这依赖于childViewControllers。虽然我同意依赖第一个类可能很脆弱，但命名您所寻找的类会使这个类看起来相当可靠。

Swift编程

你可以这样写

var containerViewController: ExampleViewController?
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
    // you can set this name in 'segue.embed' in storyboard
    if segue.identifier == "checkinPopupIdentifierInStoryBoard" {
        let connectContainerViewController = segue.destinationViewController as ExampleViewController
        containerViewController = connectContainerViewController
    }
}