Question

我正在使用Firebase身份验证在Android中创建一个简单的身份验证应用。直到现在我成功签署了用户，但问题是用户仍然登录，我找不到签署他的方法。

这是我的MainActivity.java代码

public class MainActivity extends AppCompatActivity {

    private FirebaseAuth mAuth;
    private FirebaseAuth.AuthStateListener mAuthListener;

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

        //tracking the sign in and singn out operations
        mAuth = FirebaseAuth.getInstance();
        mAuthListener = new FirebaseAuth.AuthStateListener(){
            @Override
            public void onAuthStateChanged(@NonNull FirebaseAuth firebaseAuth) {
                FirebaseUser user = firebaseAuth.getCurrentUser();
                if (user!=null){
                    System.out.println("User logged in");
                }
                else{
                    System.out.println("User not logged in");
                }
            }
        };
    }


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

        }
    }


    public void buttonClicked(View view){

        EditText editemail = (EditText) findViewById(R.id.email);
        EditText editpass = (EditText) findViewById(R.id.password);

        String email = editemail.getText().toString();
        String password = editpass.getText().toString();


        mAuth.signInWithEmailAndPassword(email, password)
                .addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
                    @Override
                    public void onComplete(@NonNull Task<AuthResult> task) {
                     //   Log.d(TAG, "signInWithEmail:onComplete:" + task.isSuccessful());
                        Toast.makeText(MainActivity.this, "Authentication Success.",
                                Toast.LENGTH_SHORT).show();
                        startActivity(new Intent(MainActivity.this,Success.class));
                        // 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.w(TAG, "signInWithEmail", task.getException());
                            Toast.makeText(MainActivity.this, "Authentication failed.",
                                    Toast.LENGTH_SHORT).show();
                        }

                        // ...
                    }
                });
    }



}

Answer 1

使用此代码FirebaseAuth.getInstance().signOut();

Answer 2

您可以直接调用此

FirebaseAuth.getInstance().signOut();

如果您想在退出后执行某些操作，请使用此操作。

public void onClick(View v) {
    if (v.getId() == R.id.sign_out) {
        AuthUI.getInstance()
            .signOut(this)
            .addOnCompleteListener(new OnCompleteListener<Void>() {
                public void onComplete(@NonNull Task<Void> task) {
                    // user is now signed out
                    startActivity(new Intent(MyActivity.this, SignInActivity.class));
                    finish();
                }
            });
        }
    }

Answer 3

试试这个

FirebaseAuth fAuth = FirebaseAuth.getInstance();
 fAuth.signOut();

Answer 4

如果您使用firebaseAuthUI，则推荐的方法是

public void onClick(View v) {
if (v.getId() == R.id.sign_out) {
    AuthUI.getInstance()
        .signOut(this)
        .addOnCompleteListener(new OnCompleteListener<Void>() {
            public void onComplete(@NonNull Task<Void> task) {
                // user is now signed out
                startActivity(new Intent(MyActivity.this, SignInActivity.class));
                finish();
            }
        });
    }
}

根据firebaseAuthUI github Guide。

Answer 5

这可以通过使用AuthStateListener

来解决

//Declaration and defination
private FirebaseAuth firebaseAuth;
FirebaseAuth.AuthStateListener authStateListener = new FirebaseAuth.AuthStateListener() {
    @Override
    public void onAuthStateChanged(@NonNull FirebaseAuth firebaseAuth) {
        if (firebaseAuth.getCurrentUser() == null){
            //Do anything here which needs to be done after signout is complete
            signOutComplete();
        }
        else {
        }
    }
};

//Init and attach
firebaseAuth = FirebaseAuth.getInstance();
firebaseAuth.addAuthStateListener(authStateListener);

//Call signOut()
firebaseAuth.signOut();

摘要：https://codepad.co/snippet/aPeehdoD

Answer 6

Firebase身份验证提供了注销方法。

 FirebaseAuth.getInstance().signOut();

Answer 7

这个只是从当前的应用程序中签出。

如果您正在使用片段，请执行此操作

AuthUI.getInstance().signOut(getActivity());

如果您正在使用某项活动，请执行此操作

AuthUI.getInstance().signOut(getApplicationContext);

<强>欢呼声！

Answer 8

FirebaseAuth.getInstance（）。signOut（）;

Answer 9

logout.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
  firebaseAuth.getInstance().signOut();
  Intent intent = new Intent(SettingsActivity.this,SignInActivity.class);
  startActivity(intent);
  }
});

Answer 10

有多种方法可以退出用户：

<强> 1。 FirebaseUI： Refarence

添加附加费：

dependencies {
    implementation 'com.firebaseui:firebase-ui-auth:4.0.0'
}

然后：

public void onClick(View v) {
if (v.getId() == R.id.sign_out) {
    AuthUI.getInstance()
        .signOut(this)
        .addOnCompleteListener(new OnCompleteListener<Void>() {
            public void onComplete(@NonNull Task<Void> task) {
                // user is now signed out
                startActivity(new Intent(MyActivity.this, SignInActivity.class));
                finish();
            }
        });
    }
}

<强> 2。 Kotlin： Referance

使用Android默认身份验证依赖项，例如： com.google.firebase:firebase-auth:16.0.1

firebase.auth().signOut().then(function() {
  // Sign-out successful.
}).catch(function(error) {
  // An error happened.
});

第3。默认使用java：

使用Android默认身份验证依赖项，例如： com.google.firebase:firebase-auth:16.0.1

FirebaseAuth mAuth = FirebaseAuth.getInstance();
try {
     mAuth.signOut();
     Toast.makeText(this, "User Sign out!", Toast.LENGTH_SHORT).show();
}catch (Exception e) {
     Log.e(TAG, "onClick: Exception "+e.getMessage(),e );
}

Answer 11

使用这个`

findViewById(R.id.signout).setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            FirebaseAuth.getInstance().signOut();
            Intent intent = new Intent(currentActivity.this, MainActivity.class);             

intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);//makesure user cant go back
                startActivity(intent);
            }
        });`

Answer 12

FirebaseAuth.getInstance().signOut();

然后，检测登录状态：

private FirebaseAuth mAuth = FirebaseAuth.getInstance()
public static boolean mAuthSignIn() {
    if (mAuth != null) {
        FirebaseUser user = mAuth.getCurrentUser();
        return user != null;
    }
    return false;
}

Answer 13

要完全注销，我建议：

mFirebaseAuth.signOut();
Auth.GoogleSignInApi.signOut(mGoogleApiClient);

Answer 14

试试这个，它对我有用。

FirebaseAuth.getInstance()
        .signOut(this)
        .addOnCompleteListener(new OnCompleteListener<Void>() {
            public void onComplete(@NonNull Task<Void> task) {
                // user is now signed out
                startActivity(new Intent(YOUR CURRENT ACTIVITY, ACTIVITY IN WHICH YOU WANT TO MOVE));
                finish();
            }
        });

如何让用户在Firebase中注销？

14 个答案: