UISheetPresentationController
参考资料：
表单可帮助用户执行与其当前环境密切相关的小范围任务。
1// MyViewController.swift
2let vc = UIViewController()
3if #available(iOS 15.0, *) {
4 if let sheet = vc.sheetPresentationController {
5 sheet.detents = [.medium(), .large()]
6 sheet.largestUndimmedDetentIdentifier = .medium
7 sheet.prefersScrollingExpandsWhenScrolledToEdge = false
8 sheet.prefersEdgeAttachedInCompactHeight = true
9 sheet.widthFollowsPreferredContentSizeWhenEdgeAttached = true
10 }
11}
12present(vc, animated: true)
Note设置 UIViewController 的 modalPresentationStyle 属性为
fullScreen时，将不会以表单的形式呈现。
