SwiftUI - PresentationButton with modal that is full screen

Question

I am trying to implement a button that presents another scene with a \"Slide from Botton\" animation.

PresentationButton looked like a good candidate, so I gave it

Answer 1

This version fixes the compile error present in XCode 11.1 as well as ensures that controller is presented in the style that is passed in.

import SwiftUI

struct ViewControllerHolder {
    weak var value: UIViewController?
}

struct ViewControllerKey: EnvironmentKey {
    static var defaultValue: ViewControllerHolder {
        return ViewControllerHolder(value: UIApplication.shared.windows.first?.rootViewController)

    }
}

extension EnvironmentValues {
    var viewController: UIViewController? {
        get { return self[ViewControllerKey.self].value }
        set { self[ViewControllerKey.self].value = newValue }
    }
}

extension UIViewController {
    func present(style: UIModalPresentationStyle = .automatic, @ViewBuilder builder: () -> Content) {
        let toPresent = UIHostingController(rootView: AnyView(EmptyView()))
        toPresent.modalPresentationStyle = style
        toPresent.rootView = AnyView(
            builder()
                .environment(\.viewController, toPresent)
        )
        self.present(toPresent, animated: true, completion: nil)
    }
}

To use this version, the code is unchanged from the previous version.

struct MyView: View {

    @Environment(\.viewController) private var viewControllerHolder: UIViewController?
    private var viewController: UIViewController? {
        self.viewControllerHolder.value
    }

    var body: some View {
        Button(action: {
           self.viewController?.present(style: .fullScreen) {
              MyView()
           }
        }) {
           Text("Present me!")
        }
    }
}