Make CollectionView Cell horizontal cell bigger than others

Question

I have a collectionView and want to make the center cell is bigger than other cells and when move to previous or next cell make it bigger in center

func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
    if collectionView == self.collectionView {
        return slidData.count
    } else {
        return categoryData.count
    }
}

func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
    if collectionView == self.collectionView {
        let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "imageCell", for: indexPath) as! SliderImgCell

        cell.categoryName.text = slidData[indexPath.row].imageTitle
        cell.detail.text = slidData[indexPath.row].imageContent
        cell.pics = slidData[indexPath.item]

        return cell
    } else{
        let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "categoryCell", for: indexPath) as! CategoryCell

        cell.categoryName.text = categoryData[indexPath.row].depName
        cell.pics = categoryData[indexPath.item]

        return cell
    }
}

Answer 1

You need to save the selected indexPath like this:

func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
    selectedIndexPath = indexPath 
}

Your collection view must confirm UICollectionViewDelegateFlowLayout. Then in sizeForItemAt method resize your cell:

func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
    if indexPath == selectedIndexPath {
        return CGSize(width: 200, height: 90)
    } else {
        return CGSize(width: 180, height: 80)
    }
}