java - 如何检测数据库中存储的谷歌登录帐户？

Question

我正在创建支持电子邮件和谷歌登录身份验证和 Firebase 数据库的用户应用程序。每次，我第一次使用 Google 帐户签名时，帐户数据都会作为新用户记录存储在 firebase 数据库中。但是，当我注销并使用之前的同一 Google 帐户登录时，我发现了问题。即使退出，我如何知道 Google 帐户已注册并存储到 Firebase？我的逻辑是当用户第一次使用Google帐户登录时，帐户数据将存储到firebase数据库中，应用程序将检测帐户是否已注册并存储到数据库中。

有与我的问题相关的LoginActivity.java类和ProfilActivity.java类的代码。

LoginActivity.java类

package co.id.roni.usertestapp;

import android.content.Intent;
import android.os.Bundle;
import android.util.Log;
import android.util.Patterns;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;

import com.google.android.gms.auth.api.signin.GoogleSignIn;
import com.google.android.gms.auth.api.signin.GoogleSignInAccount;
import com.google.android.gms.auth.api.signin.GoogleSignInClient;
import com.google.android.gms.auth.api.signin.GoogleSignInOptions;
import com.google.android.gms.common.SignInButton;
import com.google.android.gms.common.api.ApiException;
import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.Task;
import com.google.firebase.auth.AuthCredential;
import com.google.firebase.auth.AuthResult;
import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.auth.FirebaseUser;
import com.google.firebase.auth.GoogleAuthProvider;
import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;

public class LoginUserActivity extends AppCompatActivity implements View.OnClickListener {
    private static final int RC_SIGN_IN = 1001;
    private static final String TAG = "Google Activity";
    TextView tvDaftarLinkPage;
    Button SignIn;
    FirebaseAuth signInAuth;
    FirebaseUser signInAuthUser;
    EditText emailSignIn, passSignIn;
    SignInButton googleSignInButton;
    DatabaseReference reference;
    boolean isGoogleSignIn;

    GoogleSignInClient mGoogleSignInClient;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_login_user);
        SignIn = findViewById(R.id.btn_sign_in);
        tvDaftarLinkPage = findViewById(R.id.tv_register_link_text);
        emailSignIn = findViewById(R.id.edt_email_signin);
        passSignIn = findViewById(R.id.edt_pass_signin);

        googleSignInButton = findViewById(R.id.btn_sign_in_google);
        googleSignInButton.setOnClickListener(this);

        signInAuth = FirebaseAuth.getInstance();
        signInAuthUser = signInAuth.getCurrentUser();
        tvDaftarLinkPage.setOnClickListener(this);
        SignIn.setOnClickListener(this);

        reference = FirebaseDatabase.getInstance().getReference("Users");

        // Configure Google Sign In
        GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
                .requestIdToken(getString(R.string.default_web_client_id))
                .requestEmail()
                .build();

        mGoogleSignInClient = GoogleSignIn.getClient(this, gso);
    }

    @Override
    public void onClick(View view) {
        switch (view.getId()) {
            case R.id.tv_register_link_text:
                startActivity(new Intent(LoginUserActivity.this, RegisterUserActivity.class));
                finish();
                break;
            case R.id.btn_sign_in:
                signInProcess();
                break;
            case R.id.btn_sign_in_google:
                signInWithGoogle();
                break;
        }

    }

//    sign In with Google
    private void signInWithGoogle() {
        Intent signInIntent = mGoogleSignInClient.getSignInIntent();
        startActivityForResult(signInIntent, RC_SIGN_IN);
    }


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

        // Result returned from launching the Intent from GoogleSignInApi.getSignInIntent(...);
        if (requestCode == RC_SIGN_IN) {
            Task<GoogleSignInAccount> task = GoogleSignIn.getSignedInAccountFromIntent(data);
            try {
                // Google Sign In was successful, authenticate with Firebase
                GoogleSignInAccount account = task.getResult(ApiException.class);
                firebaseAuthWithGoogle(account);
            } catch (ApiException e) {
                // Google Sign In failed, update UI appropriately
                Log.w(TAG, "Google sign in failed", e);
                // [START_EXCLUDE]
//                updateUI(null);
                // [END_EXCLUDE]
            }
        }
    }

    //process google account sign in
    private void firebaseAuthWithGoogle(final GoogleSignInAccount account) {
        Log.d(TAG, "firebaseAuthWithGoogle:" + account.getId());
        AuthCredential credential = GoogleAuthProvider.getCredential(account.getIdToken(), null);
        signInAuth.signInWithCredential(credential)
                .addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
                    @Override
                    public void onComplete(@NonNull Task<AuthResult> task) {
                        if (task.isSuccessful()) {
                            // Sign in success, update UI with the signed-in user's information
                            Log.d(TAG, "signInWithCredential:success");

                            //variabel isGoogleSignIn is used for checking sign in google

                            isGoogleSignIn = true;
                            FirebaseUser user = signInAuth.getCurrentUser();

                            //the problem code is here! How I can detect the google user account has stored and registered 
                            if (user != null) {
                                String uid = user.getUid();
                                reference.child(uid).child("uid").setValue(uid);
                                reference.child(uid).child("name").setValue(user.getDisplayName());
                                reference.child(uid).child("email").setValue(user.getEmail());
                                reference.child(uid).child("photo").setValue(String.valueOf(user.getPhotoUrl()));


                            }
                            startActivity(new Intent(LoginUserActivity.this, ProfilUserActivity.class));
                            finish();

                        } else {
                            // If sign in fails, display a message to the user.
                            Log.w(TAG, "signInWithCredential:failure", task.getException());
                        }

                        // [START_EXCLUDE]
//                        hideProgressDialog();
                        // [END_EXCLUDE]
                    }
                });
    }

//this method for login with email. this is success
    private void signInProcess() {
        final String email = emailSignIn.getText().toString();
        final String pass = passSignIn.getText().toString();

        if (email.isEmpty()) {
            emailSignIn.setError("Tidak boleh kosong");
        } else if (!Patterns.EMAIL_ADDRESS.matcher(email).matches()) {
            emailSignIn.setError("Email tidak valid");
        } else if (pass.isEmpty()) {
            passSignIn.setError("Password tidak boleh kosong");
        } else if (pass.length() <= 6) {
            passSignIn.setError("Password minimal 6 karakter");
        } else {
            signInAuth.signInWithEmailAndPassword(email, pass).addOnCompleteListener(LoginUserActivity.this, new OnCompleteListener<AuthResult>() {
                @Override
                public void onComplete(@NonNull Task<AuthResult> task) {
                    if (task.isSuccessful()) {
                        startActivity(new Intent(LoginUserActivity.this, ProfilUserActivity.class));
                        finish();
                    } else {
                        Log.e("Pesan", "Gagal Sign In : " + task.getException());
                    }
                }
            });
        }
    }

}
```

ProfilActivity.java 类

package co.id.roni.usertestapp;

import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;

import com.google.android.gms.auth.api.Auth;
import com.google.android.gms.auth.api.signin.GoogleSignInClient;
import com.google.android.gms.auth.api.signin.GoogleSignInOptions;
import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.common.api.ResultCallback;
import com.google.android.gms.common.api.Status;
import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.Task;
import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.auth.FirebaseUser;
import com.google.firebase.database.DataSnapshot;
import com.google.firebase.database.DatabaseError;
import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;
import com.google.firebase.database.ValueEventListener;
import com.squareup.picasso.Picasso;

public class ProfilUserActivity extends AppCompatActivity implements GoogleApiClient.OnConnectionFailedListener, View.OnClickListener {
    TextView namaProfile, emailProfile;
    ImageView photoImageProfile;
    FirebaseAuth firebaseAuthMain;
    FirebaseUser user;
    DatabaseReference profileDb;
    GoogleSignInClient googleSignInClient;
    boolean isGoogleSignIn;
    private static final String TAG ="Pesan" ;
    GoogleSignInOptions gso;


    private GoogleApiClient mGoogleApiClient;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_profil_user);
        Button btnEditProfile = findViewById(R.id.btn_edit_profile);
        Button btnSignOut = findViewById(R.id.btn_sign_out);
        namaProfile = findViewById(R.id.tv_nama_profil);
        emailProfile = findViewById(R.id.tv_email_profil_page);
        photoImageProfile = findViewById(R.id.img_profile_page);

        firebaseAuthMain = FirebaseAuth.getInstance();
        user = firebaseAuthMain.getCurrentUser();

        if(user != null){
            showProfile();

        }

        btnEditProfile.setOnClickListener(this);
        gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
                .requestEmail()
                .build();
        mGoogleApiClient = new GoogleApiClient.Builder(this)
                .enableAutoManage(this, this)
                .addApi(Auth.GOOGLE_SIGN_IN_API,gso)
                .build();
        btnSignOut.setOnClickListener(this);
    }

    private void showProfile() {
        profileDb = FirebaseDatabase.getInstance().getReference().child("Users").child(user.getUid());
        profileDb.getRef().addValueEventListener(new ValueEventListener() {
            @Override
            public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
                emailProfile.setText(dataSnapshot.child("email").getValue().toString());
                namaProfile.setText(dataSnapshot.child("name").getValue().toString());
                Picasso.get().load(dataSnapshot.child("photo").getValue().toString()).centerCrop().fit().into(photoImageProfile);
            }

            @Override
            public void onCancelled(@NonNull DatabaseError databaseError) {
                Log.e("Pesan", "Gagal Load"+databaseError.getMessage());
            }
        });

    }

    @Override
    public void onClick(View view) {
        if(view.getId() == R.id.btn_edit_profile){
            startActivity(new Intent(ProfilUserActivity.this, EditProfileActivity.class));
            finish();
        }
        if(view.getId() == R.id.btn_sign_out){
            if(user != null){
                firebaseAuthMain.signOut();
                //every sign out, user can choose another gmail but the problem is how to know the gmail has registered
                Auth.GoogleSignInApi.signOut(mGoogleApiClient).setResultCallback(new ResultCallback<Status>() {
                    @Override
                    public void onResult(@NonNull Status status) {
                        startActivity(new Intent(ProfilUserActivity.this, UserMainActivity.class));
                        finish();
                    }
                });

//                goog.signOut().addOnCompleteListener(this, new OnCompleteListener<Void>() {
//                    @Override
//                    public void onComplete(@NonNull Task<Void> task) {
//
//                    }
//                });
            }
            else{
                Log.e("Status", "Gagal Keluar");
            }


        }

    }

    @Override
    public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {
        Log.e(TAG, "message"+connectionResult.getErrorMessage());
    }
}

我希望应用程序能够检测到哪些 Gmail 帐户已注册并存储到 Firebase 数据库中，以便个人资料页面仅显示数据库中的数据

Answer 1

将您的代码替换为以下代码。由于它会检查 user 是否不为 null 并将执行代码，直到到达启动 Activity 函数为止，您的所有 Google 数据都将存储在 Firebase 中。如果未发送数据，则可能无法启动 Activity 。

if (user != null) {
     String uid = user.getUid();
     reference.child(uid).child("uid").setValue(uid);
     reference.child(uid).child("name").setValue(user.getDisplayName());
     reference.child(uid).child("email").setValue(user.getEmail());
     reference.child(uid).child("photo").setValue(String.valueOf(user.getPhotoUrl()));
     startActivity(new Intent(LoginUserActivity.this, ProfilUserActivity.class));
     finish();
 }