title: UICollectionView cannot display customized cell content
body: <p>I tried to create a dummy photo app with UICollectionView. My Xcode version is 7.2 and Swift version 2.1.1. I use <a href="http://i.stack.imgur.com/YXyzo.png" rel="nofollow">Storyboard</a> to build the UI part by following the tutorial from <a href="http://www.raywenderlich.com/78550/beginning-ios-collection-views-swift-part-1" rel="nofollow">http://www.raywenderlich.com/78550/beginning-ios-collection-views-swift-part-1</a></p>
  
  <p>In Swift 2.0, the <strong>UICollectionViewDataSource</strong> is inherited from <strong>UICollectionViewController</strong>, we don't need to explicitly declare those protocols. I implemented the required override methods for DataSource, and also register the customized cell in <strong>viewDidLoad()</strong> in the <strong>UICollectionViewController</strong>. I put a test <strong>Label</strong> in my cell to check whether it works or not. Unfortunately, the label never appear after I launch the app. I attach some of my code below as reference:</p>
  
  <p><strong>UICollectionViewController</strong></p>
  
  <pre><code>class VacationsCollectionViewController: UICollectionViewController {
  
      private let reuseIdentifier = "VacationCell"
  
      override func viewDidLoad() {
          super.viewDidLoad()
          self.collectionView!.registerClass(VacationsCollectionViewCell.self, forCellWithReuseIdentifier: reuseIdentifier)
      }
  
      // MARK: UICollectionViewDataSource
  
      override func numberOfSectionsInCollectionView(collectionView: UICollectionView) -&gt; Int {
          // #warning Incomplete implementation, return the number of sections
          return 1
      }
  
      override func collectionView(collectionView: UICollectionView, numberOfItemsInSection section: Int) -&gt; Int {
          // #warning Incomplete implementation, return the number of items
          return 1
      }
  
      override func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -&gt; UICollectionViewCell {
          let cell = collectionView.dequeueReusableCellWithReuseIdentifier(reuseIdentifier, forIndexPath: indexPath) as! VacationsCollectionViewCell
  
          // Configure the cell
          cell.backgroundColor = UIColor.blueColor()
          cell.CellText.text = "Show me the money"
  
          return cell
      }
  }
  </code></pre>
  
  <p><strong>UICollectionViewCell</strong></p>
  
  <pre><code>class VacationsCollectionViewCell: UICollectionViewCell {
      @IBOutlet weak var CellText: UILabel!
  }
  </code></pre>
  
  <p>Any idea why the label never show up in my dummy app?</p>