UIView.animateWithDuration不对单独的视图控制器进行动画处理

Question

将动画设置为反复淡入和淡出。 “ viewSmall”和“ viewBig”是UIImageViews。

查看情节提要镜头

class TestViewController: UIViewController {

    @IBOutlet weak var viewBig: UIImageView!
    @IBOutlet weak var viewSmall: UIImageView!

    override func viewDidLoad() {
        super.viewDidLoad()

        // Do any additional setup after loading the view.

        animate()
    }

    func animate() {
        UIView.animateWithDuration(0.5,
                                   delay: 0,
                                   options: [.Repeat, .Autoreverse],
                                   animations: {
                                    self.viewSmall.alpha = 0
            },
                                   completion: nil)

        UIView.animateWithDuration(0.5,
                                   delay: 0,
                                   options: [.Repeat, .Autoreverse],
                                   animations: {
                                    self.viewBig.alpha = 0
            },
                                   completion: nil)
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }
}

这段代码不会在仅有的几个视图控制器上进行动画处理，而且我认为这些视图控制器似乎是独立的，与其他视图控制器无关。 因为此代码在连接到导航视图控制器的视图控制器上可以完美工作。

如何在独立的视图控制器上制作它？ 请帮忙。

Answer 1

找到了一个绝妙的解决方案。 使用dispatch_after捕获持续时间和延迟。

func animate(){
    dispatch_after(dispatch_time(DISPATCH_TIME_NOW, Int64(0.0 * Double(NSEC_PER_SEC))), dispatch_get_main_queue(), {

        // Animate the transition
        UIView.animateWithDuration(0.5,
                               delay: 0,
                               options: [.Repeat, .Autoreverse],
                               animations: {
                                self.viewSmall.alpha = 0
        },
                               completion: nil)

        UIView.animateWithDuration(0.5,
                               delay: 0,
                               options: [.Repeat, .Autoreverse],
                               animations: {
                                self.viewBig.alpha = 0
        },
                               completion: nil)
    })
}

来源： Swift UIView animateWithDuration完成关闭立即调用