Question

在我的应用中，我使用了Firebase身份验证来使用Google帐户登录。当用户登录时，MainActivity应该会启动，但这会启动一次并仍显示login活动。这是我的清单：

<?xml version="1.0" encoding="utf-8"?>

<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.SEND_SMS" />
<uses-permission android:name="android.permission.RECORD_AUDIO" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
/>
<application
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:name = ".BFD"
    android:label="@string/app_name"
    android:roundIcon="@mipmap/ic_launcher_round"
    android:supportsRtl="true"
    android:theme="@style/AppTheme">

    <activity
        android:name=".login"
        android:label="@string/app_name"
        android:theme="@style/AppTheme.NoActionBar">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
    <activity android:name=".MainActivity"/>
    <activity
        android:name=".ContactSetup"
        android:parentActivityName=".ContextSetup" />
    <activity
        android:name=".EditContacts"
        android:parentActivityName=".EditContacts" />
    <activity
        android:name=".HowTo"
        android:parentActivityName=".MainActivity" />
    <activity
        android:name=".AboutDevs"
        android:parentActivityName=".MainActivity" />
    <activity
        android:name=".RecordHistory"
        android:parentActivityName=".MainActivity" />
    <activity
        android:name=".CustomText"
        android:parentActivityName=".ContextSetup" />
    <activity
        android:name=".ContextSetup"
        android:parentActivityName=".MainActivity" />
</application>

login.java如下：

public class login extends AppCompatActivity {

private SignInButton signInButton;
private static final int RC_SIGN_IN = 1;
private GoogleApiClient mGoogleApiClient;
private FirebaseAuth mAuth;
private FirebaseAuth.AuthStateListener mAuthListener;

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

    //FirebaseApp.initializeApp(getApplicationContext());

    mAuth = FirebaseAuth.getInstance();
    mAuthListener = new FirebaseAuth.AuthStateListener() {
        @Override
        public void onAuthStateChanged(@NonNull FirebaseAuth firebaseAuth) {
            if(firebaseAuth.getCurrentUser() != null){
                startActivity(new Intent(login.this, MainActivity.class));
            }
        }
    };

    signInButton = findViewById(R.id.SignIn);
    GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
            .requestIdToken(getString(R.string.default_web_client_id))
            .requestEmail()
            .build();

    mGoogleApiClient = new GoogleApiClient.Builder(this)
            .enableAutoManage(this, new GoogleApiClient.OnConnectionFailedListener() {
                @Override
                public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {
                   // Toast.makeText(getApplicationContext(), "Error", Toast.LENGTH_LONG).show();
                }
            })
            .addApi(Auth.GOOGLE_SIGN_IN_API, gso)
            .build();

    signInButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            signIn();
        }
    });

    }

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

private void signIn() {
    Intent signInIntent = Auth.GoogleSignInApi.getSignInIntent(mGoogleApiClient);
    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("Signing in: ", "Google sign in failed", e);
            // ...
        }
    }
}

private void firebaseAuthWithGoogle(GoogleSignInAccount acct) {
    AuthCredential credential = GoogleAuthProvider.getCredential(acct.getIdToken(), null);
    mAuth.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");
                        FirebaseUser user = mAuth.getCurrentUser();
                        //updateUI(user);
                    } else {
                        // If sign in fails, display a message to the user.
                        //Log.w(TAG, "signInWithCredential:failure", task.getException());
                        //Snackbar.make(findViewById(R.id.main_layout), "Authentication Failed.", Snackbar.LENGTH_SHORT).show();
                        //updateUI(null);
                    }

                    // ...
                }
            });

}

}

我在这里做错了什么阻止了主要活动的开始。任何建议/意见将不胜感激:)）

Answer 1

登录成功后，您是否更新了您的活动？我看到你的updateUI方法是评论。当用户成功登录时，不会给出任何语句。
还要根据您的项目检查您的Auth客户端ID。如果真有帮助你，请回复我。

Answer 2

使用addAuthStateListener（AuthStateListener）和removeAuthStateListener（AuthStateListener）注册或取消注册侦听器。资料来源：https://firebase.google.com/docs/reference/android/com/google/firebase/auth/FirebaseAuth.AuthStateListener

所以我猜mAuth.addAuthStateListener（mAuthListener）; 是初始化authStateListener后你需要的。

另外在您设置用户的onComplete中，我认为那是你应该打电话给你的新活动的地方。我建议将用户保存在实例中或将其传递给intent。取决于您的需求。

我没有尝试这个，但onComplete和authStateListener中的简单调试和断点会指向正确的方向。

祝你好运，希望我帮助过。在附注中，类和活动应以大写字母LoginActivity开头（是活动名称的约定）

成功登录后，MainActivity未启动

2 个答案: