对于SwiftUI只有代码，这里有一个问题和答案：Make sheet the exact size of the content inside基于此，iOS 16.0+用于从UIViewcontroller进行演示的解决方案将是：

func presentSwiftUIPageSheet() {
    var sheetHeight = CGFloat.zero
    let swiftUIView = SwiftUIView()
        .readSize { sheetHeight = $0.height }

    let hostingController = UIHostingController(rootView: swiftUIView)
    hostingController.modalPresentationStyle = .pageSheet
    hostingController.isModalInPresentation = false
    hostingController.sheetPresentationController?.detents = [.custom { _ in 0 },
                                                              .large()]
    DispatchQueue.main.asyncAfter(deadline: .now() + 0.1) {
        hostingController.sheetPresentationController?.animateChanges {
            hostingController.sheetPresentationController?.detents = [.custom { _ in sheetHeight },
                                                                      .large()]
        }
    }
    present(hostingController, animated: true)
}

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使用SwiftUI扩展：

private struct SizePreferenceKey: PreferenceKey {
  static var defaultValue: CGSize = .zero
  static func reduce(value: inout CGSize, nextValue: () -> CGSize) { value = nextValue() }
}

extension View {

    func readSize(onChange: @escaping (CGSize) -> Void) -> some View {
        background(
            GeometryReader { proxy in
                Color.clear
                    .preference(key: SizePreferenceKey.self, value: proxy.size)
            }
        ).onPreferenceChange(SizePreferenceKey.self, perform: onChange)
    }
}

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