Swift 实现可拖动收回转场动画

首先上效果：

1589698106340.gif

Demo地址：

HSTransitionDemo
目前没有支持pod，主要是不会弄，执行注册cocoapodz命令一直失败

pod trunk register xxxx@qq.com 'xxx'
[!] An internal server error occurred. Please check for any known status issues at https://twitter.com/CocoaPods and try again later.

如何使用

    var aniamtion: HSCoverVerticalTransition!
    public init() {
        super.init(nibName:nil, bundle:nil)
        self.aniamtion = HSCoverVerticalTransition.init(present: self, dismiss: true)
        self.transitioningDelegate = self.aniamtion
    }
    
    override func viewDidLoad() {
        super.viewDidLoad()
        self.preferredContentSize = CGSize.init(width: self.view.bounds.width, height: 450)
    }

原理

原理暂时就不讲了，网上有很多大神的文章，以后有时间可以整理补充