How can I add multiple collection views in a UIViewController in Swift?

Question

I tried many days to realise this:

I want to add in my UIViewController two di

Answer 1

This is possible, you just need to add each UICollectionView as a subview, and set the delegate and dataSource to your UIViewController.

Here's a quick example. Assuming you have one UICollectionView working, you should be able to adapt this code to your own uses to add a second fairly easily:

let collectionViewA = UICollectionView()
let collectionViewB = UICollectionView()
let collectionViewAIdentifier = "CollectionViewACell"
let collectionViewBIdentifier = "CollectionViewBCell"

override func viewDidLoad() {
    // Initialize the collection views, set the desired frames
    collectionViewA.delegate = self
    collectionViewB.delegate = self

    collectionViewA.dataSource = self
    collectionViewB.dataSource = self

    self.view.addSubview(collectionViewA)
    self.view.addSubview(collectionViewB)
}

In the cellForItemAtIndexPath delegate function:

func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell {
    if collectionView == self.collectionViewA {
        let cellA = collectionView.dequeueReusableCellWithReuseIdentifier(collectionViewAIdentifier) as UICollectionViewCell

        // Set up cell
        return cellA
    }

    else {
        let cellB = collectionView.dequeueReusableCellWithReuseIdentifier(collectionViewBIdentifier) as UICollectionViewCell

        // ...Set up cell

        return cellB
    }
}

In the numberOfItemsInSection function:

func collectionView(collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
    if collectionView == self.collectionViewA {
        return 0 // Replace with count of your data for collectionViewA
    }

    return 0 // Replace with count of your data for collectionViewB
}