WebviewExample.swift

struct ContentView: View {
    
    
    @State var urlString = "https://www.google.com"
    @State var url: URL?

    var body: some View {
        NavigationStack {
            WebViewReader { proxy in
                Webview(url: url ?? URL(string: "https://www.google.com")!)
                    .toolbar {
                        ToolbarItem(placement: .topBarTrailing) {
                            Button("Reload") {
                                proxy.reload()
                            }
                        }
                        
                        ToolbarItem(placement: .topBarLeading) {
                            Button("Back") {
                                proxy.goBack()
                            }
                        }
                            
                    }
                    .navigationTitle(proxy.title)
                    .navigationBarTitleDisplayMode(.inline)
            }
            .safeAreaInset(edge: .bottom) {
                TextField("Enter URL", text: $urlString)
                    .textFieldStyle(.roundedBorder)
                    .onSubmit {
                        url = URL(string: urlString)
                    }
                    .padding()
                    .background(.ultraThinMaterial)
            }
            .onChange(of: url) {
                urlString = $0?.absoluteString ?? ""
            }
        }
    }
}


struct WebViewProxy {
    fileprivate var box: Box<WKWebView?>? = Box(nil)
    
    var title: String {
        box?.value?.title ?? ""
    }
    
    func reload() {
        box?.value?.reload()
    }
    
    func goBack() {
        box?.value?.goBack()
    }
}

extension EnvironmentValues {
    @Entry var box: Box<WKWebView?>?
}

class Box<T> {
    var value: T
    init(_ value: T) {
        self.value = value
    }
}

struct WebViewReader<C: View>: View {
    @State var proxy = WebViewProxy()
    let content: (WebViewProxy) -> C
        
    var body: some View {
        content(proxy)
            .environment(\.box, proxy.box)
    }
}
    

struct Webview: UIViewRepresentable {
    let url: URL
    
    func makeUIView(context: Context) -> WKWebView{
        let webView = WKWebView()
        webView.load(URLRequest(url: url))
        return webView
    }
    
    func updateUIView(_ uiView: WKWebView, context: Context) {
        if uiView.url != url {
            uiView.load(URLRequest(url: url))
        }
        context.environment.box?.value = uiView
    }
}