如何在登录后在SwiftUI中显示新视图

import SwiftUI

struct ContentView: View {
    @State private var isLoggedIn = false
    
    var body: some View {
        if isLoggedIn {
            MainView()
        } else {
            LoginView(isLoggedIn: $isLoggedIn)
        }
    }
}

struct LoginView: View {
    @Binding var isLoggedIn: Bool
    @State private var username = ""
    @State private var password = ""
    
    var body: some View {
        VStack {
            TextField("Username", text: $username)
                .textFieldStyle(RoundedBorderTextFieldStyle())
                .padding()
            
            SecureField("Password", text: $password)
                .textFieldStyle(RoundedBorderTextFieldStyle())
                .padding()
            
            Button(action: {
                // 验证用户名和密码
                if username == "admin" && password == "password" {
                    isLoggedIn = true
                }
            }) {
                Text("Login")
                    .padding()
                    .foregroundColor(.white)
                    .background(Color.blue)
                    .cornerRadius(10)
            }
        }
        .padding()
    }
}

struct MainView: View {
    var body: some View {
        VStack {
            Text("Welcome to the Main View!")
                .font(.title)
                .padding()
            
            // 添加其他功能模块
        }
    }
}

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