Swift无法从上到下呈现视图控制器

Question

在我的应用程序中,我必须从上到下呈现屏幕,我尝试了下面的代码,它给出了相同的正常呈现风格.

        let screen = self.storyboard?.instantiateViewController(withIdentifier: "Screen1p5") as? Screen1p5
        let transition = CATransition()
        transition.duration = 0.5
        transition.type = kCATransitionPush
        transition.subtype = kCATransitionFromTop
        view.window!.layer.add(transition, forKey: kCATransition)
        self.present(screen!, animated: true, completion: nil)

Answer 1

对于您需要设置subtype的CATransition,以kCATransitionFromBottom和连击设置动画animated来false与present(_:animated:completion:).

let screen = self.storyboard?.instantiateViewController(withIdentifier: "Screen1p5") as? Screen1p5
let transition = CATransition()
transition.duration = 0.5
transition.type = kCATransitionPush
transition.subtype = kCATransitionFromBottom
view.window!.layer.add(transition, forKey: kCATransition)
self.present(screen!, animated: false, completion: nil)

因解除设定subtype的CATransition到kCATransitionFromTop.

let transition = CATransition()
transition.duration = 0.5
transition.type = kCATransitionPush
transition.subtype = kCATransitionFromTop
view.window!.layer.add(transition, forKey: kCATransition)
self.dismiss(animated: false)