Swift：在添加项目时更改UICollectionView中单元格布局的宽度

Question

I'm new to swift , i want to make a UICollectionViewCell layout to be dynamic example: if we have an item added to look like this:

1.if we have one item it look like this

2.If we have two items added to look like this:

3. if we have item 3 again to look like this :

This process proceeds this way, as long as there are items

Thanks!

Answer 1

This is method of UICollectionViewDelegateFlowLayout for the size of items. Just check for total item count odd/even and based on that decide you cell width.

func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {

    if arrList.count % 2 == 0 {

        let width = (collectionView.frame.width-20)/2
        let height : CGFloat = 100.0
        return CGSize(width: width, height: height)

    }else {

        if arrList.count-1 == indexPath.row {
            let width = collectionView.frame.width-10
            let height : CGFloat = 100.0
            return CGSize(width: width, height: height)
        }else{
            let width = (collectionView.frame.width-20)/2
            let height : CGFloat = 100.0
            return CGSize(width: width, height: height)
        }
    }

}

This is interspacing methods.

//these methods are to configure the spacing between items

func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, insetForSectionAt section: Int) -> UIEdgeInsets {
    return UIEdgeInsetsMake(0,5,5,5)
}

func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, minimumInteritemSpacingForSectionAt section: Int) -> CGFloat {
    return 10
}

func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, minimumLineSpacingForSectionAt section: Int) -> CGFloat {
    return 10
}