UICollectionView must be initialized with a non-nil layout parameter'
<p>I am trying to use two collection views inside of a view controller and I get this error message as a result? Can you point out what i am missing to correct this issue? Thanks in advance.. 
Below is my code in the view controller named "OtherViewController".</p>

<p>class OtherViewController : UIViewController, UICollectionViewDataSource, UICollectionViewDelegate {</p>

<pre><code>//1. CREATE A VARIABLE FOR YELLOW ARRAY SO THAT I CAN DEFINE A STRING
var exploreArray = [String]()
var exploreHeader = [String]()
var yellowImages = [String]()
var explorecategories = [String]()


@IBOutlet weak var mycollectionView: UICollectionView!


var collectionViewA = UICollectionView()
let collectionViewB = UICollectionView()
let collectionViewAIdentifier = "yellowCell"
let collectionViewBIdentifier = "yellowCell2"

 override func viewDidLoad() {
    super.viewDidLoad()


    // Do any additional setup after loading the view.

        collectionViewA.delegate = self
        collectionViewB.delegate = self

        collectionViewA.dataSource = self
        collectionViewB.dataSource = self


        self.view.addSubview(collectionViewA)
        self.view.addSubview(collectionViewB)
</code></pre>

<p>}</p>

<p>func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {</p>

<pre><code>   if collectionView == self.collectionViewA {
         return exploreArray.count        }

    return 1 // Replace with count of your data for collectionViewB

} 
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -&gt; UICollectionViewCell {
   if collectionView == self.collectionViewA{

        let cellA = collectionView.dequeueReusableCell(withReuseIdentifier: "yellowCell", for: indexPath) as! yellowCell
                // Set up cell

    //DISPLAY TITLE LABEL
    cellA.yLabel.text = exploreHeader[indexPath.row]

    //DISPLAY IMAGES
    cellA.yellowImages.image  = UIImage(named:yellowImages [indexPath.row])

    //DISPLAY DESCRIPTION
    cellA.yellowTextField.text = exploreArray [indexPath.row]

    return cellA
    }

    else {

       let cellB =  collectionView.dequeueReusableCell(withReuseIdentifier: "yellowCell2", for: indexPath) as! yellowCell2

    cellB.labe2.text = "Dolphin"
</code></pre>

<p>//just radom label to to see if cellB will appear in collection view</p>

<pre><code>               return cellB
    }

    }
</code></pre>