SwiftUI UIViewRepresentable nested view example

UIParentView.swift

import SwiftUI

struct ContentView: View {
    @State private var toggle = false
    
    var body: some View {
        CustomParentView {
            Button {
                toggle.toggle()
            } label: {
                Text(toggle.description)
            }
        }
    }
}

struct CustomParentView<Content: View>: UIViewRepresentable {
    let content: Content
    
    @inlinable init(@ViewBuilder content: () -> Content) {
        self.content = content()
    }
    
    func makeUIView(context: Context) -> UIView {
        let view = UIView()
        
        let hostingController = context.coordinator.hostingController
        hostingController.view.frame = view.bounds
        hostingController.view.autoresizingMask = [.flexibleWidth, .flexibleHeight]
        
        view.addSubview(hostingController.view)
        
        return view
    }
    
    func updateUIView(_ uiView: UIView, context: Context) {
        context.coordinator.hostingController.rootView = self.content
    }
    
    class Coordinator: NSObject {
        var hostingController: UIHostingController<Content>
        
        init(hostingController: UIHostingController<Content>) {
            self.hostingController = hostingController
        }
    }
    
    func makeCoordinator() -> Coordinator {
        return Coordinator(hostingController: UIHostingController(rootView: content))
    }
    
}