In a UICollectionView, the cells will not sit on the bottom

Question

Note it turned out it was a simple mistake the cells would not \"sit on the bottom\". However, it\'s an interesting question: \"how to move the cells up and

Answer 1

Here's one "brute force" way to solve the problem -- write your own FlowLayout!!

It works ...

class SimpleFlowLayout: UICollectionViewFlowLayout {


override init() {
    super.init()

    initialize()
}

required init?(coder aDecoder: NSCoder) {
    super.init(coder: aDecoder)
    initialize()
}

func initialize() {
    self.scrollDirection = .horizontal
    self.minimumInteritemSpacing = 0.0
    self.minimumLineSpacing = 0.0

}

override var collectionViewContentSize: CGSize {

    return super.collectionViewContentSize
}

override func layoutAttributesForElements(in rect: CGRect) -> [UICollectionViewLayoutAttributes]? {


    let allItems = super.layoutAttributesForElements(in: rect)
    for  attribute in allItems! {
        print ("attribute.frame.origin.y  .....  \(attribute.frame.origin.y)")
        attribute.frame = CGRect(x: attribute.frame.origin.x,
                                 y: attribute.frame.origin.y + 34,
                             width: attribute.frame.size.width,
                            height: attribute.frame.size.height)

            // "go figure" ... add 34
    }

    return allItems;

}

The way you "set" a UICollectionViewFlowLayout is basically like this...

class YourFancyDisplay: UICollectionViewController {

    override func viewDidLoad() {
        super.viewDidLoad()

        collectionView!.contentInset = UIEdgeInsetsMake(0, 0, 0, 0)
        collectionView!.collectionViewLayout = SimpleFlowLayout()
        ...

Answer 2

Try this. hopefully, it can help

-(CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath {
    return collectionView.frame.size;
}

---

(For future readers, indeed you also typically need the other one ...)

-(CGSize) collectionView:(UICollectionView *)collectionView
     layout:(UICollectionViewLayout *)collectionViewLayout
     sizeForItemAtIndexPath:(NSIndexPath *)indexPath
    {
    return self.view.frame.size;
    }

-(UIEdgeInsets)collectionView:(UICollectionView *)collectionView
   layout:(UICollectionViewLayout*)collectionViewLayout
   insetForSectionAtIndex:(NSInteger)section
    {
    return UIEdgeInsetsMake(0,0,0,0);   //t,l,b,r
    }