如何在SwiftUI macOS应用程序中模糊背景？

我想使突出显示的部分透明和模糊，类似于其他macOS应用程序。我在网上找到有关如何使用NSViewController进行模糊处理的文章，我对此并不完全了解。我是新手，还不了解如何使用Viewcontrollers。我的代码如下。任何帮助，将不胜感激！

import SwiftUI

struct ContentView: View {

    var body: some View {
        VStack {
            GeometryReader { geometry in
                NavigationView{
                    HStack(spacing: 0) {
                        ZStack{

                            Text("BitMessenger")
                                .font(.title)
                                .fontWeight(.light)
                                .foregroundColor(Color.white)
                        }
                        .frame(width: geometry.size.width/2, height: geometry.size.height+20)
                        .background(Color(red: 0.07, green: 0.07, blue: 0.07, opacity: 1.0))
                        VStack{

                            HStack {
                                Text("Sign Up")
                                    .font(.headline)
                                    .padding(.top, 30.0)
                                Spacer()
                            }




                            HStack {
                                Text("Welcome to BitMessenger")
                                    .font(.subheadline)
                                    .foregroundColor(Color.gray)
                                    .padding(.top, 10.0)
                                Spacer()
                            }

                            Form {
                                VStack{
                                    HStack {
                                        Text("Full Name")
                                            .font(.caption)
                                            .foregroundColor(Color.white)
                                            .padding(.top, 10.0)
                                        Spacer()
                                    }





                                    TextField("ex. John Doe", text: /*@START_MENU_TOKEN@*//*@PLACEHOLDER=Value@*/.constant("")/*@END_MENU_TOKEN@*/)




                                    HStack {
                                        Text("Email Address")
                                            .font(.caption)
                                            .foregroundColor(Color.white)
                                            .padding(.top, 10.0)
                                        Spacer()
                                    }





                                    TextField("[email protected]", text: /*@START_MENU_TOKEN@*//*@PLACEHOLDER=Value@*/.constant("")/*@END_MENU_TOKEN@*/)





                                    HStack {
                                        Text("Password")
                                            .font(.caption)
                                            .foregroundColor(Color.white)
                                            .padding(.top, 10.0)
                                        Spacer()
                                    }



                                    TextField("AIOFHWaowhf", text: /*@START_MENU_TOKEN@*//*@PLACEHOLDER=Value@*/.constant("")/*@END_MENU_TOKEN@*/)

                                    HStack {
                                        Button(action: /*@START_MENU_TOKEN@*/{}/*@END_MENU_TOKEN@*/) {
                                            Text("Register")
                                                .padding(.horizontal, 10.0)
                                        }
                                        .padding(.all)
                                    }

                                }
                            }
                            .padding(.top)

                            Spacer()

                            NavigationLink(destination: ContentView()) {
                                Text("Already have an Account? Login")
                                .font(.caption)
                                    .foregroundColor(Color.gray)
                                    .background(Color.clear)
                            }
                            .padding(.bottom)
                            .foregroundColor(Color.clear)


                        }
                        .padding(.horizontal, 30.0)
                        .frame(width: geometry.size.width / 2, height: geometry.size.height+20)
                        .background(Color.black.opacity(0.9))
                    }.edgesIgnoringSafeArea(.all)
                }

            }
            .edgesIgnoringSafeArea(.all)
            .frame(width: 750.0, height: 500.0)

        }

    }
}


class MyViewController: NSViewController {

    var visualEffect: NSVisualEffectView!

    override func loadView() {
        super.loadView()

        visualEffect = NSVisualEffectView()
        visualEffect.translatesAutoresizingMaskIntoConstraints = false
        visualEffect.material = .dark
        visualEffect.state = .active
        visualEffect.blendingMode = .behindWindow
        view.addSubview(visualEffect)

        visualEffect.leadingAnchor.constraint(equalTo: view.leadingAnchor).isActive = true
        visualEffect.trailingAnchor.constraint(equalTo: view.trailingAnchor).isActive = true
        visualEffect.topAnchor.constraint(equalTo: view.topAnchor).isActive = true
        visualEffect.bottomAnchor.constraint(equalTo: view.bottomAnchor).isActive = true


    }
}


struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}