SwiftuiViewModule.swift

import ExpoModulesCore
import UIKit
import SwiftUI

// Native view and module definition
public class SwiftuiViewModule: Module {
  public func definition() -> ModuleDefinition {
    Name("SwiftuiView")
      View(SwiftuiView.self) {
          // Define your props here
          Prop("name") { (view, name: String) in
              view.name = name
          }
          Prop("options") { (view, options: [String]) in
              view.options = options
          }
      }
  }
}

// Here you can initialize your ViewController and add it as a subview.
class SwiftuiView: ExpoView {
    // When props are updated, update the view controller's view
    var name = "" {
        didSet {
            myViewController?.updateView(withName: name, withOptions: options)
        }
    }
    
    var options: [String] = [] {
        didSet {
            myViewController?.updateView(withName: name, withOptions: options)
        }
    }
    
    private var myViewController: MyViewController?
    
    required init(appContext: AppContext? = nil) {
        super.init(appContext: appContext)
        // init the view controller
        let vc = MyViewController()
        vc.view.frame = CGRect(x: 0, y: 0, width: 10, height: 200) // TODO: find a better way to do this
        // add it as a subview of the ExpoView
        addSubview(vc.view)
        myViewController = vc
    }
}

// ViewController responsible for embedding your SwiftUI view into the view hierarchy using a UIHostingController
class MyViewController: UIViewController {
    // init the hosting controller. set the rootView to your SwiftUI view
    let hostingController = UIHostingController(rootView: MySwiftUIView())

    override func viewDidLoad() {
        super.viewDidLoad()
        hostingController.view.translatesAutoresizingMaskIntoConstraints = false
        view.addSubview(hostingController.view)
        // setup constraints
        NSLayoutConstraint.activate([
            hostingController.view.topAnchor.constraint(equalTo: self.view.topAnchor),
            hostingController.view.bottomAnchor.constraint(equalTo: self.view.bottomAnchor),
            hostingController.view.leftAnchor.constraint(equalTo: self.view.leftAnchor),
            hostingController.view.rightAnchor.constraint(equalTo: self.view.rightAnchor)
        ])
    }
    
    // Update the hosting controller's root view with updated prop values
    func updateView(withName name: String, withOptions options: [String]) {
        hostingController.rootView = MySwiftUIView(name: name, options: options)
    }
}

// Your SwiftUI view
struct MySwiftUIView: View {
    var name = ""
    var options: [String] = []
    @State var isOpen = false
    @State var picker = 0
    @State var isScaled = false
    
    var body: some View {
        VStack(spacing: 20) {
            Text("SwiftUI + Expo")
                .font(.largeTitle)
                .scaleEffect(isScaled ? 1.5 : 1.0)
                .foregroundColor(isScaled ? .purple : .black)
            
            Button("Animations work too!") {
                withAnimation {
                    isScaled.toggle()
                }
            }
            
            if #available(iOS 14.0, *) {
                Label(name, systemImage: name)
                    .padding()
                    .foregroundColor(.blue)
            }
        
            Picker("Picker", selection: $picker, content: {
                ForEach(Array(options.enumerated()), id: \.1) { index, option in
                    Text(option)
                        .tag(index)
                }
            }).pickerStyle(.segmented)
            
            if #available(iOS 16.0, *) {
                Button("Toggle Sheet") {
                    isOpen.toggle()
                }.sheet(isPresented: $isOpen) {
                    Text("Sheet content")
                        .presentationDetents([.medium, .large])
                }.padding(.bottom, 100)
            }
            
        }.background(Color(UIColor.systemGroupedBackground))
    }
}