Android Facebook 登录。 防止按钮更改为“注销”

Question

Let me describe the application im trying to do using Kotlin, on Android Studio.

Splash Screen => Login Screen => Main App

Splash Screen: Just a photo Login Screen: Provides different ways of logging (Google, Facebook, etc) MainActivity: Allows you to log off, in that case, you must return to "Login Screen"

So far I have been working only with Facebook Login. I managed to place the button, make it work, and get a proper uid. The trouble is that, when that button is clicked, it automatically switches to "Log Out". So, when I go back from my MainActivity to my Login Screen, instead of having the button to Login again, im having a "Log Out" button, when account is actually already logged out.

Is there a way to prevent this button from changing? I have been reading tons of documentation, but havent found anything useful. Is my idea incorrect? Or is there a better way to do this? Note that everytime I Leave the LoginScreen, I place a finish(). The reason of this was to try to reset the activity, and make it work as if the program was running from scratch.

Variables defined on LoginScreen

    private var mCallBackManager : CallbackManager?= null
    private var mFirebaseAuth : FirebaseAuth?= null

On create function

override fun onCreate(savedInstanceState: Bundle?)
    {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.lay_login_screen)

        //-----------Inicializadores-Facebook---------------
        mFirebaseAuth = FirebaseAuth.getInstance()
        FacebookSdk.sdkInitialize(getApplicationContext())
        mCallBackManager = CallbackManager.Factory.create()
        //--------------------------------------------------


        //-----------Boton-Facebook-------------------------
        Button_LoginScreen_LoginFace.setOnClickListener()
        {
            iniciarSesionFacebook();
        }
        //--------------------------------------------------

    }

private fun iniciarSesionFacebook()
    {
        Button_LoginScreen_LoginFace.registerCallback(mCallBackManager, object : FacebookCallback<LoginResult>
        {

            override fun onSuccess(result: LoginResult?)
            {
                d(getString(R.string.TAG_FacebookLogin),"Login Correct")
                handleFacebookToken(result!!.accessToken)
            }

            override fun onCancel()
            {
                d(getString(R.string.TAG_FacebookLogin),"Login cancelled")
            }

            override fun onError(error: FacebookException?)
            {
                d(getString(R.string.TAG_FacebookLogin),"Login Error")
            }
        })
    }
    private fun handleFacebookToken(accessToken: AccessToken?)
    {
        val credential = FacebookAuthProvider.getCredential(accessToken!!.token)

        mFirebaseAuth!!.signInWithCredential(credential).addOnFailureListener()
        {error->
            d(getString(R.string.TAG_FacebookLogin),"Error 1"+error.message)
        }
            .addOnSuccessListener { resultado->

                startActivity(Intent(this, MainActivity::class.java))
                finish()
            }
    }

    override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?)
    {
        super.onActivityResult(requestCode, resultCode, data)
        mCallBackManager!!.onActivityResult(requestCode,resultCode,data)
    }

Finally, this is how I "Log Out" from MainActivity, and return to LoginScreen

class MainActivity : AppCompatActivity()
{

    //----------Variables-Globales----------------
    private var mFirebaseAuth : FirebaseAuth?= null
    //--------------------------------------------

    override fun onCreate(savedInstanceState: Bundle?)
    {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        //-------Inicializo-Variables------------------------
        mFirebaseAuth = FirebaseAuth.getInstance()
        //---------------------------------------------------

        Button_MainActity_LogOf.setOnClickListener{
            val firebaseaux=mFirebaseAuth
            firebaseaux?.signOut()
            startActivity(Intent(this, ActivityLoginScreen::class.java))

        }
    }
}

This is how the LoginScreen looks the first time is ran.

This is how it looks after manually logging of. Note that is not only the appearence of the code, the code itself changes. Now the button doesnt allow you to LogIn.

Just to add some extra information, i have found this property on the docs

Configuration: auto_logout_link

HTML5 Attribute: data-auto-logout-link

Description: If its activated, the button will be replaced by a LogOut button if the user has already logged in

Options: True,False

This es EXACTLY what im looking for. But, from what I can see, that is only ment for webpages and not android. Does somebody know how to touch this configuration in android? or the equivalent adroid option? I will add the link where I found the property. https://developers.facebook.com/docs/facebook-login/web/login-button/

Thanks in advance

Answer 1

Ok, after some time I managed to solve the Issue. I was logging out from the Firebase Authentication, but not from Facebook authentication. I didnt manage to stop the button from behaving like it does, but at least the behaviour now is correct. I will share my new LogOut code.

        Button_MainActity_LogOf.setOnClickListener{
        FirebaseAuth.getInstance().signOut()  //Log out from Firebase
        if(isFacebookLogin())   //Check if logged in on facebook
        {
            LoginManager.getInstance().logOut()  //Log out from facebook
        }
          //Here i should log out from other providers

        startActivity(Intent(this, ActivityLoginScreen::class.java))
    }

private fun isFacebookLogin(): Boolean
{
    return AccessToken.getCurrentAccessToken() !=null
}