如果用戶已經登錄，則在我的Android應用程序中使用谷歌登錄會遇到麻煩

Question

如果用戶已經登錄，我在我的應用程序中使用谷歌登錄時遇到問題。當我第一次登錄時它工作得很好，因為它要求我輸入密碼和其他信息但是如果用戶已經登錄我通常會瘦應該打開選擇這樣的帳戶菜單：

[截圖] [https://androidclarified.com/wp-content/uploads/2018/11/Screenshot_2018-11-11-20-53-15-306_com.google.android.gms_-768x1365.png]

但在我的情況下會發生以下情況：[problem-gif] [https://gph.is/g/ZYBxy14]

public class LoginActivity extends AppCompatActivity implements
        View.OnClickListener{


    private static final String TAG = "LoginActivity1";
    private static final int RC_SIGN_IN = 9001;
    private GoogleSignInClient mGoogleSignInClient;

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_login);

        GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
                .requestEmail()
                .build();

        mGoogleSignInClient = GoogleSignIn.getClient(this, gso);
        SignInButton signInButton = findViewById(R.id.sign_in_button);
        signInButton.setOnClickListener(this);
    }

    private void signIn() {
        Toast.makeText(this, "button works", Toast.LENGTH_SHORT).show();
        Intent signInIntent = mGoogleSignInClient.getSignInIntent();
        startActivityForResult(signInIntent, RC_SIGN_IN);
    }
    private void signOut() {
        mGoogleSignInClient.signOut()
                .addOnCompleteListener(this, new OnCompleteListener<Void>() {
                    @Override
                    public void onComplete(@NonNull Task<Void> task) {
                        // [START_EXCLUDE]
                        updateUI(null);
                        // [END_EXCLUDE]
                    }
                });
    }

    private void updateUI(@Nullable GoogleSignInAccount account) {
        if (account != null) {
            Log.d(TAG, account.getDisplayName());
        } else {
            Log.d(TAG, "account is null");
        }
    }

    @Override
    public void onStart() {
        super.onStart();

        // [START on_start_sign_in]
        // Check for existing Google Sign In account, if the user is already signed in
        // the GoogleSignInAccount will be non-null.
        GoogleSignInAccount account = GoogleSignIn.getLastSignedInAccount(this);
        updateUI(account);
        // [END on_start_sign_in]
    }

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

        // Result returned from launching the Intent from GoogleSignInClient.getSignInIntent(...);
        if (requestCode == RC_SIGN_IN) {
            // The Task returned from this call is always completed, no need to attach
            // a listener.
            Task<GoogleSignInAccount> task = GoogleSignIn.getSignedInAccountFromIntent(data);
            handleSignInResult(task);
        }
    }

    private void handleSignInResult(Task<GoogleSignInAccount> completedTask) {
        try {
            GoogleSignInAccount account = completedTask.getResult(ApiException.class);

            // Signed in successfully, show authenticated UI.
            updateUI(account);
        } catch (ApiException e) {
            // The ApiException status code indicates the detailed failure reason.
            // Please refer to the GoogleSignInStatusCodes class reference for more information.
            Log.d(TAG, "signInResult:failed code=" + e.getStatusCode());
            updateUI(null);
        }
    }

    @Override
    public void onClick(View v) {
        switch (v.getId()) {
            case R.id.sign_in_button:
                signIn();
                break;

        }
    }
}

Answer 1

您已經在onStart（）回調方法中調用了getLastSignedInAccount方法。 因此，當您使用您的Gmail帳戶成功登錄后，每次進入此活動后，它都不會顯示帳戶選擇對話框。 所以，不用擔心這個。

您可以通過以下代碼注銷您的用戶。 那么你將獲得第一次獲得的相同的登錄模式。

    private void signOut() {

    mGoogleSignInClient.signOut()
            .addOnCompleteListener(this, new OnCompleteListener<Void>() {
                @Override
                public void onComplete(@NonNull Task<Void> task) {
                    // ...
                }
            });
}