Android Firebase Facebook 身份验证注销功能

Question

我正在将 facebook 身份验证方法与 firebase 一起使用，但我不知道如何正确注销用户。在我按下“继续使用 Facebook”按钮并允许它访问我的个人资料后，该按钮会更改为“注销”并在我单击它时显示一个对话框。问题是它实际上并没有将我注销并且状态仍然是登录。

我找到了 here如何在我的应用程序中从 Firebase 和 Facebook 注销用户，但我不知道将这两行放在哪里。我正在寻找注销功能或类似功能。

我找到了 here (different here)我的解决方案可能是什么，但它非常困惑并且无法理解。你能帮帮我吗？

@Override
protected void onCreate(Bundle savedInstanceState) {
    mAuth = FirebaseAuth.getInstance();

    super.onCreate(savedInstanceState);
    FacebookSdk.sdkInitialize(getApplicationContext());
    AppEventsLogger.activateApp(this);
    setContentView(R.layout.activity_login);

    mCallbackManager = CallbackManager.Factory.create();
    LoginButton loginButton = (LoginButton) findViewById(R.id.button_facebook_login);
    loginButton.setReadPermissions("email", "public_profile");
    loginButton.registerCallback(mCallbackManager, new FacebookCallback<LoginResult>() {
        @Override
        public void onSuccess(LoginResult loginResult) {
            Log.e(TAG, "facebook:onSuccess:" + loginResult);
            handleFacebookAccessToken(loginResult.getAccessToken());
        }

        @Override
        public void onCancel() {
            Log.e(TAG, "facebook:onCancel");
            // ...
        }

        @Override
        public void onError(FacebookException error) {
            Log.e(TAG, "facebook:onError", error);
            // ...
        }
    });

    mAuthListener = new FirebaseAuth.AuthStateListener() {
        @Override
        public void onAuthStateChanged(@NonNull FirebaseAuth firebaseAuth) {
            final FirebaseUser user = firebaseAuth.getCurrentUser();
            if (user != null) {
                // User is signed in
                Log.e(TAG, "onAuthStateChanged:signed_in:" + user.getUid());

                DatabaseReference myRef = database.getReference("Users");
                myRef.addValueEventListener(new ValueEventListener() {
                    boolean userExists = false;
                    User userFirebase;

                    @Override
                    public void onDataChange(DataSnapshot dataSnapshot) {
                        for (DataSnapshot mydata : dataSnapshot.getChildren()){
                            userFirebase = mydata.getValue(User.class);

                            if(userFirebase.getEmail().equals(user.getEmail())){
                                Log.e(TAG, "User found in the database");
                                userExists = true;
                                Intent intent = new Intent(getBaseContext(), ActivityMain.class);
                                startActivity(intent);
                                break;
                            }
                        }

                        if (!userExists){
                            DatabaseReference mDatabase = FirebaseDatabase.getInstance().getReference();
                            mDatabase.child("Users").push().setValue(new User(user.getDisplayName(),user.getEmail(),0,0));

                            Intent intent = new Intent(getBaseContext(), ActivityMain.class);
                            startActivity(intent);
                        }
                    }

                    @Override
                    public void onCancelled(DatabaseError databaseError) {

                    }
                }); // checks if the user is in database and writes him if not

            } else {
                // User is signed out
                Log.e(TAG, "onAuthStateChanged:signed_out");
            }
        }
    };


}

@Override
public void onStart() {
    super.onStart();
    mAuth.addAuthStateListener(mAuthListener);
}

@Override
public void onStop() {
    super.onStop();
    if (mAuthListener != null) {
        mAuth.removeAuthStateListener(mAuthListener);
    }
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);

    // Pass the activity result back to the Facebook SDK
    mCallbackManager.onActivityResult(requestCode, resultCode, data);
}

private void handleFacebookAccessToken(AccessToken token) {
    Log.e(TAG, "handleFacebookAccessToken:" + token);

    AuthCredential credential = FacebookAuthProvider.getCredential(token.getToken());
    mAuth.signInWithCredential(credential)
            .addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
                @Override
                public void onComplete(@NonNull Task<AuthResult> task) {
                    Log.e(TAG, "signInWithCredential:onComplete:" + task.isSuccessful());

                    // If sign in fails, display a message to the user. If sign in succeeds
                    // the auth state listener will be notified and logic to handle the
                    // signed in user can be handled in the listener.
                    if (!task.isSuccessful()) {
                        Log.e(TAG, "signInWithCredential", task.getException());
                        Toast.makeText(getBaseContext(), "Authentication failed.",
                                Toast.LENGTH_SHORT).show();
                    }

                    // ...
                }
            });
}

Answer 1

您需要实现自己的按钮并使用上述 2 种方法添加和 OnClickListener :

Button logoutButton = (Button) findViewById(R.id.logout_button);
logoutButton.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View view) {
        FirebaseAuth.getInstance().signOut();
        LoginManager.getInstance().logOut();
    }
});

您不能使用 facebook 注销按钮，因为它只会让您退出 facebook，您还需要 firebase 注销。