Center the last row in UICollectionView - ios

Question

I have a 7 cells UICollectionView displayed like this
X X
X X
X X
X
I need it to be displayed like this
X X
X X
X X
X
How's this can be done in Swift?

Answer 1

you can do this simple calculation in your collectionViewLayout function.
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
//return itemSize
let spaceBetweenCell :CGFloat = 0
let screenWidth = UIScreen.main.bounds.size.width - CGFloat(2 * spaceBetweenCell)
let totalSpace = spaceBetweenCell * 1.0
if indexPath.row == categories.count-1 {
// check if last cell is odd
if categories.count % 2 == 1 {
return CGSize(width: screenWidth , height: (screenWidth-totalSpace)/4) // all Width and same previous height
}else {
return itemSize
}
}else{
return itemSize
}
}

Answer 2

Here is my code just i add datasource count to 7 items
Also make sure that you create your cell
let cell = collectionView.dequeueReusableCell(withReuseIdentifier:
"cell", for: indexPath) as! UICollectionViewCell
, Spacing between items =4
Code
extension ViewController :UICollectionViewDelegate , UICollectionViewDelegateFlowLayout,UICollectionViewDataSource{
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
return 7 // data source
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "cell", for: indexPath) as! UICollectionViewCell
cell.backgroundColor = .red
return cell
}
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
let spaceBetweenCell :CGFloat = 4.0
let screenWidth = UIScreen.main.bounds.size.width - CGFloat(2 * spaceBetweenCell)
let totalSpace = spaceBetweenCell * 1.0; // there is one space in 2 item
if indexPath.row == 6 { // indexpath.row == datasource.count - 1
if 6 % 2 == 1{ // check if last cell is odd
return CGSize(width: screenWidth , height: (screenWidth-totalSpace)/2) // all Width and same previous height
}else{
return CGSize(width: (screenWidth - totalSpace)/2, height: (screenWidth-totalSpace)/2)
}
}else{
return CGSize(width: (screenWidth - totalSpace)/2, height: (screenWidth-totalSpace)/2)
}
}
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, minimumLineSpacingForSectionAt section: Int) -> CGFloat {
return 4.0
}
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, minimumInteritemSpacingForSectionAt section: Int) -> CGFloat {
return 4.0
}
}