Swift 协议语法，其中 Self: 既是 UICollectionViewDataSource 又是 UICollectionViewDelegate

Question

我正在尝试创建一个协议，该协议会自动将 UICollectionView 添加到符合要求的任何 UIViewController。

这是我当前的代码：

protocol ReusableNavigation {
    var actionContainer: UIView! { get }
    func addActionMenuCollection()
}

extension ReusableNavigation where Self: UICollectionViewDataSource {
    func addActionMenuCollection() {
        let layout: UICollectionViewFlowLayout = UICollectionViewFlowLayout()

        layout.sectionInset = UIEdgeInsets(top: 20, left: 10, bottom: 10, right: 10)
        layout.itemSize = CGSize(width: 60, height: 60)
        let actionMenu:UICollectionView = UICollectionView(frame: self.actionContainer.frame, collectionViewLayout: layout)

        actionMenu.dataSource = self
        actionMenu.delegate = self
        actionMenu.register(UINib(nibName: "ActionCell", bundle: nil), forCellWithReuseIdentifier: "actionCell")
        actionMenu.semanticContentAttribute = UISemanticContentAttribute.forceRightToLeft
        self.actionContainer.addSubview(actionMenu)
    }
}

显然，上面的代码在我尝试设置 actionMenu 委托时出错，因为 self 只是一个 UICollectionViewDataSource

我这辈子都想不出协议扩展的语法，其中 self 等于 UICollectionViewDataSource 和 UICollectionViewDelegate。

可能吗？想法？

Answer 1

添加约束以逗号分隔

extension ReusableNavigation where Self: UICollectionViewDataSource,  Self: UICollectionViewDelegate { ...

或与号连接

extension ReusableNavigation where Self: UICollectionViewDataSource & UICollectionViewDelegate

Swift 协议语法，其中 Self: 既是 UICollectionViewDataSource 又是 UICollectionViewDelegate

Swift protocol syntax where Self: is both UICollectionViewDataSource and UICollectionViewDelegate

protocols

swift