collectionView footer not showing

Question

I've checked the section footer as shown in the screenshot below.

I've also implemented the dataSource method:

  override func collectionView(collectionView: UICollectionView, viewForSupplementaryElementOfKind kind: String, atIndexPath indexPath: NSIndexPath) -> UICollectionReusableView {
    if kind == UICollectionElementKindSectionHeader {
      var header = collectionView.dequeueReusableSupplementaryViewOfKind(kind, withReuseIdentifier: "Header", forIndexPath: indexPath) as? DetailHeader
      if header == nil {
        header = DetailHeader()
      }
      return header!
    } else {
      println("footer")
      var footer = collectionView.dequeueReusableSupplementaryViewOfKind(kind, withReuseIdentifier: "Footer", forIndexPath: indexPath) as! UICollectionReusableView
      return footer
    }

  }

I was able to display my header, but my footer is never displayed. The println never triggers either.

Answer 1

1. Screen shot from storyboard:

2.My code:

import UIKit

class BaseCVC: UICollectionViewController, UICollectionViewDelegateFlowLayout {

    override func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell {

        let cell = collectionView.dequeueReusableCellWithReuseIdentifier("cvcCell", forIndexPath: indexPath)

        return cell;
    }

    override func collectionView(collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
        return Int(2)
    }

    func collectionView(collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, referenceSizeForFooterInSection section: Int) -> CGSize {

        return CGSizeMake(self.view.frame.size.width, 20)
    }

    override func collectionView(collectionView: UICollectionView, viewForSupplementaryElementOfKind kind: String, atIndexPath indexPath: NSIndexPath) -> UICollectionReusableView {

        if kind == UICollectionElementKindSectionHeader {
            let header = collectionView.dequeueReusableSupplementaryViewOfKind(kind, withReuseIdentifier: "header", forIndexPath: indexPath)

            return header

        } else {
            print("footer")
            let footer = collectionView.dequeueReusableSupplementaryViewOfKind(kind, withReuseIdentifier: "footer", forIndexPath: indexPath)
            return footer
        }
    }
}

3. Result in simulator:

4. Important note: I've used Xcode 7 beta 5 (Swift 2.0)