Swift - Change UICollectionViewCell size programmatically - ios

Question

I am struggling to change the size my items in the CollectionView.
Custom Flowlayout class found here:
This is my CollectionView:
class ExampleViewController: UIViewController, UICollectionViewDataSource {
let theCollectionView: UICollectionView = {
let v = UICollectionView(frame: CGRect.zero, collectionViewLayout: UICollectionViewFlowLayout())
v.translatesAutoresizingMaskIntoConstraints = false
v.backgroundColor = .white
v.contentInsetAdjustmentBehavior = .always
v.layer.cornerRadius = 30
return v
}()
let columnLayout = FlowLayout(
itemSize: CGSize(width: 50, height: 50),
minimumInteritemSpacing: 10,
minimumLineSpacing: 10,
sectionInset: UIEdgeInsets(top: 20, left: 20, bottom: 10, right: 20)
)
I tried changing the itemSize but that doesnt do anything.

Answer 1

You didn't assigned you flowLayout to the collectionView either try:
theCollectionView.collectionViewLayout = columnLayout or
First define your layout :
let columnLayout = FlowLayout( ...
Then define your collectionView like this:
let theCollectionView: UICollectionView = {
let v = UICollectionView(frame: CGRect.zero, collectionViewLayout:columnLayout)

Answer 2

Here is Code for CollectionViewCell Size Change
(Note:- Change values according to your Requirement!)
let layout: UICollectionViewFlowLayout = UICollectionViewFlowLayout()
layout.sectionInset = UIEdgeInsets(top: 20, left: 0, bottom: 10, right: 0)
layout.itemSize = CGSize(width: screenWidth/4, height: screenWidth/4)
layout.minimumInteritemSpacing = 0
layout.minimumLineSpacing = 0
cell2.collectionView2.collectionViewLayout = layout