swift - 从 UICollectionReusableView 转为 ImagePicker

Question

我的 UICollectionReusableView 有一个类，但我需要该视图中的一个按钮来执行从 UICollectionView 到 imagePicker 的 segue。我曾尝试使用委托，但我不断为委托获得零。

protocol ShouldSegueToImagePickerDelegate{
    func shouldSegue()
}

class ProfileHeaderCollectionReusableView: UICollectionReusableView{

   var delegate: ShouldSegueToImagePickerDelegate!

   @IBAction func pressedChangeBGPicButton(sender: AnyObject) {
        delegate.shouldSegue()
    }


class ProfileCollectionViewController: UICollectionViewController, UICollectionViewDelegateFlowLayout, ShouldSegueToImagePickerDelegate, UIImagePickerControllerDelegate, UINavigationControllerDelegate{

  var imagePicker = UIImagePickerController()

  func shouldSegue() {
      imagePicker.allowsEditing = false
       imagePicker.sourceType = .PhotoLibrary
       self.presentViewController(imagePicker, animated: true, completion: nil)
   }

  func imagePickerController(picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : AnyObject]) {
        imagePicker.dismissViewControllerAnimated(true, completion: nil)
    }

  func imagePickerControllerDidCancel(picker: UIImagePickerController) {
        imagePicker.dismissViewControllerAnimated(true, completion: nil)
  }