ios - Swift 2 - 两个 UICollectionViewController 之间的协议(protocol)委托(delegate)

Question

我正在尝试在两个 UICollectionViewController 之间创建一个协议(protocol)委托(delegate)。使用我拥有的代码，我没有收到任何错误或警告，但是，我无法让委托(delegate)工作。我错过了什么？

第二个收藏 View

    public protocol LettersCollectionViewDelegate: class {

        func DidSelectLetter(collectioView: UICollectionView,letter: Character, resultString:String)

    }

    class LettersCollectionView: UICollectionViewController {

        // DELEGATE
        weak var delegate: LettersCollectionViewDelegate?

    override func collectionView(collectionView: UICollectionView, didSelectItemAtIndexPath indexPath: NSIndexPath) {

            let cell : UICollectionViewCell = collectionView.cellForItemAtIndexPath(indexPath)! as! LetterCellView



           delegate?.DidSelectLetter(collectionView, letter: "T", resultString:"TestString")

    }

}

第一个 Collection View

class AnswerCollectionView: UICollectionViewController {

   let lettersView = LettersCollectionView()

   override func viewDidLoad() {
        super.viewDidLoad()

        self.lettersView.delegate = self

    }

}

extension AnswerCollectionView: LettersCollectionViewDelegate {

    func DidSelectLetter(collectioView: UICollectionView, letter: Character, resultString: String) {

        print(letter)
    }
}

更新

Answer 1

您需要将委托(delegate)作为嵌入在 Root View Controller 中的 AnswerCollectionView 的实例。同样，您需要在 Root View 中的 LettersCollectionView 实例上设置委托(delegate)。 let lettersView = LettersCollectionView() 创建一个新实例。

您可以在 Root View Controller 的 prepareForSegue 中获取所需的引用。您需要在 Storyboard标识符中提供两个嵌入的 segue，以便识别它们。

class ViewController: UIViewController {
   var lettersView: LettersCollectionView?
   var answersView: AnswersCollectionView?

   override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
       if segue.identifier == "lettersSegue" {
           let lettersView = segue.destinationViewController as? LettersCollectionView
       } else if segue.identifier = "answersSegue" {
           let answersView = segue.destinationViewController as? AnswersCollectionView
       }

       self.lettersView?.delegate = self.answersView
}