在SWIFT4.2中NSCollectionView的SupplementaryElementKind字符串值中使用什么

Question

在SWIFT4.2之前，我可以创建一个NSCollectionView头，如下所示：

func collectionView(_ collectionView: NSCollectionView, viewForSupplementaryElementOfKind kind: NSCollectionView.SupplementaryElementKind, at indexPath: IndexPath) -> NSView {
  let view = collectionView.makeSupplementaryView(ofKind: .sectionHeader, withIdentifier: NSUserInterfaceItemIdentifier(rawValue: "Header"), for: indexPath as IndexPath) as! Header

  view.sectionTitle.stringValue = collectionSections[indexPath.section]
  return view
}

如果我没记错的话，.sectionHeader是来自NSCollectionView.SupplementaryElementKind的一个enum。但是医生们说NSCollectionView.SupplementaryElementKind是String。

这就留给我更新的SWIFT4.2代码，如下所示：

func collectionView(_ collectionView: NSCollectionView, viewForSupplementaryElementOfKind kind: NSCollectionView.SupplementaryElementKind, at indexPath: IndexPath) -> NSView {
  let view = collectionView.makeSupplementaryView(ofKind: "?????", withIdentifier: NSUserInterfaceItemIdentifier(rawValue: "Header"), for: indexPath as IndexPath) as! Header

  view.sectionTitle.stringValue = collectionSections[indexPath.section]
  return view
}

我不清楚我应该为ofKind参数(String)包括哪些内容。那串对应的是什么？在我的xib文件中，我没有看到任何与它相关联的东西。

Answer 1

我想通了。您只需从它所在的kind委托方法中传入makeSupplementaryView参数。

let view = collectionView.makeSupplementaryView(ofKind: kind, withIdentifier: NSUserInterfaceItemIdentifier(rawValue: "Header"), for: indexPath as IndexPath) as! Header