调整 UICollectionView 中特定部分的插图

Question

1. insetForSectionAtIndex (on DelegateFlowLayout) enables one to set insets for all cells within a section

2. sectionInset (on FlowLayout) enables one to set insets that applies to all sections.

However, I am looking for a way of applying insets to only one specific section - is this possible?

Answer 1

You must have to implement UICollectionViewDelegateFlowLayout to your class with this method:

For Swift 4

func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, insetForSectionAt section: Int) -> UIEdgeInsets {

    var edgeInsets = UIEdgeInsets()
    if section == THE_SECTION_YOU_WANT {
        // edgeInsets configuration stuff
    }

    return edgeInsets;
}

For Swift 3

func collectionView(collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, insetForSectionAtIndex section: Int) -> UIEdgeInsets {

    var edgeInsets = UIEdgeInsets()
    if section == THE_SECTION_YOU_WANT {
        // edgeInsets configuration stuff
    }

    return edgeInsets;

}

Answer 2

for swift 4 is named:

func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, insetForSectionAt section: Int) -> UIEdgeInsets {
...

Answer 3

You'd do something like this from the UICollectionViewDelegateFlowLayout protocol:

func collectionView(_ collectionView: UICollectionView,
                        layout collectionViewLayout: UICollectionViewLayout,
                        insetForSectionAt section: Int) -> UIEdgeInsets {

        switch section {
        case 0:
            return UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 0)
        case 1:
            return UIEdgeInsets(top: 10, left: 0, bottom: 10, right: 0)
        }
    }