ios - 动画委托(delegate)未转换为 Swift 3.0

Question

我想实现 CABasicAnimation 并在动画完成时通知 UIViewController。来自这个资源:

http://www.informit.com/articles/article.aspx?p=1168314&seqNum=2

我知道我可以将 viewcontroller 指定为动画的委托(delegate)并覆盖 viewcontroller 中的 animationDidStop 方法。但是，当我将以下代码行转换为 Swift 时:

[animation setDelegate:self];

像这样:

animation.delegate = self//没有setDelegate方法

XCode 提示:

Cannot assign value of type 'SplashScreenViewController' to type 'CAAnimationDelegate?'

我做错了什么？我错过了什么吗？

Answer 1

您需要确保您的 viewController 符合 CAAnimationDelegate。

class SplashScreenViewController: UIViewController, CAAnimationDelegate {

    // your code, viewDidLoad and what not

    override func viewDidLoad() {
        super.viewDidLoad()

        let animation = CABasicAnimation()
        animation.delegate = self
        // setup your animation

    }

    // MARK: - CAAnimation Delegate Methods
    func animationDidStart(_ anim: CAAnimation) {

    }

    func animationDidStop(_ anim: CAAnimation, finished flag: Bool) {

    }

    // Add any other CAAnimationDelegate Methods you want

}

您还可以使用扩展来符合委托(delegate):

extension SplasScreenViewController: CAAnimationDelegate {
    func animationDidStart(_ anim: CAAnimation) {

    }

    func animationDidStop(_ anim: CAAnimation, finished flag: Bool) {

    }
}