I want to move the view when I log in successfully

Question

    Button {
                
                if(UserApi.isKakaoTalkLoginAvailable()){
                    UserApi.shared.loginWithKakaoTalk { (oauthToken, error) in
                        print(oauthToken)
                        print(error)
                    }
                } else {
                    UserApi.shared.loginWithKakaoAccount {(oauthToken, error) in
                        print(oauthToken)
                        print(error)
                    }
                }
                UserApi.shared.loginWithKakaoAccount(prompts: [.Login]) {(oauthToken, error) in
                    if let error = error {
                        print(error)
                    } else {
                        print("LoginSuccess")
                            MainView()// I want to go to this view 
                        _ = oauthToken
                    }
                }
            }

I tried navigation, but it didn't work

I want to call View when Token is here Token type is Bool

Answer 1

you could try this:

@State var showMainView = false   // <-- here

if showMainView {  // <-- here
    MainView() // I want to go to this view
} else {
    Button {
        if(UserApi.isKakaoTalkLoginAvailable()){
            UserApi.shared.loginWithKakaoTalk { (oauthToken, error) in
                print(oauthToken)
                print(error)
            }
        } else {
            UserApi.shared.loginWithKakaoAccount {(oauthToken, error) in
                print(oauthToken)
                print(error)
            }
        }
        UserApi.shared.loginWithKakaoAccount(prompts: [.Login]) {(oauthToken, error) in
            if let error = error {
                print(error)
            } else {
                print("LoginSuccess")
                self.showMainView = true   // <-- here
                // or DispatchQueue.main.async { self.showMainView = true }
                _ = oauthToken
            }
        }
    }
}

You should also read this: https://developer.apple.com/tutorials/swiftui/

Note, it would be better to do all these UserApi stuff in a separate dedicated class, rather than inside the Button.

EDIT-1: you can also use NavigationLink, for example:

struct ContentView: View {
    @State var showMainView = false
    
    var body: some View {
        NavigationView {
            VStack {
                Button("Login") { doAPIStuff() }
                NavigationLink("", destination: MainView(), isActive: $showMainView)
            }
        }
    }
    
    func doAPIStuff() {
        if(UserApi.isKakaoTalkLoginAvailable()){
            UserApi.shared.loginWithKakaoTalk { (oauthToken, error) in
                print(oauthToken)
                print(error)
            }
        } else {
            UserApi.shared.loginWithKakaoAccount {(oauthToken, error) in
                print(oauthToken)
                print(error)
            }
        }
        UserApi.shared.loginWithKakaoAccount(prompts: [.Login]) {(oauthToken, error) in
            if let error = error {
                print(error)
            } else {
                print("LoginSuccess")
                DispatchQueue.main.async { self.showMainView = true } // <-- here
                _ = oauthToken
            }
        }
    }
}