Q:

How do I get UICollectionView to continuously scroll horizontally instead of creating a second row?

What is the correct way to adjust the width of the UICollectionView to match the number of cells * their width in order to prevent the UICollectionView from creating a second row in my horizontal collection view.
Is there a specific method to implement for the CollectionView which allows me to set this?
Currently looks like: 

Currently, I'm implementing the following methods:
func numberOfSections(in collectionView: UICollectionView)

func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int)

func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath)

func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewDelegateFlowLayout, sizeForItemAt indexPath: IndexPath)

A:

first set your collectionView FlowLayout scrollDirection to horizontal.
let myColl:UICollectionView = {
    let layout = UICollectionViewFlowLayout()
    layout.scrollDirection = .horizontal
    let coll = UICollectionView(frame: .zero, collectionViewLayout: layout)
    return coll
}()

then Set your collectionview height constraint equal (or little bit grater) to the cell height
myColl.heightAnchor.constraint(equalToConstant: 50).isActive = true

set your cell size in here 
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
        return CGSize(width: view.frame.width-32, height: 50)
    }

