Question

Firebase数据库连接每秒都会反复连接和断开，直到应用程序未关闭。由于这种波动：
1. FirebaseDatabase无法从firebase服务器保存和接收数据。
2. ValueEventListener未调用。
代码已经在以下设备中进行了测试，并且在两个设备中都出现了问题： -
1. 模拟器
  
  Google Play服务10.0.84
  Android版6.0 dependencies{ compile 'com.google.firebase:firebase-database:10.0.1' compile 'com.google.firebase:firebase-auth:10.0.1' }
2. 三星Galaxy J2
  Google Play服务10.2.97
  Android版本5.1.1
  dependencies{ compile 'com.google.firebase:firebase-database:10.0.1' compile 'com.google.firebase:firebase-auth:10.0.1' }
重现问题的步骤：
1. 将设备时钟时间设置为当前时间。
2. 执行TestActivity.java
  当此活动第一次执行时，用户将使用FirebaseAuth匿名登录，等待几秒钟用户将成功登录。现在转到第3步。
3. 按下关闭应用程序。
4. 现在将设备时钟时间增加2天或更多。
5. 再次打开应用程序并检查logcat。问题将立即发生或在几分钟后或有时甚至在1或2小时后发生。如果没有立即出现问题，请关闭应用程序并在几分钟或几小时后打开它（当设备闲置2-3小时后，肯定会出现问题）;
stackoverflow链接，我认为与此问题有关 Firebase .info/connected showing wrong connection states

产生问题的代码是

package com.app.sample;
import android.os.Bundle;
import android.os.Handler;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.Task;
import com.google.firebase.auth.AuthResult;
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;

public class TestActivity extends AppCompatActivity {
    private final String TAG = "TestActivity";
    Handler handler = new Handler();
    private ValueEventListener valueEventListener = new ValueEventListener() {
        @Override
        public void onDataChange(DataSnapshot snapshot) {
            boolean connected = snapshot.getValue(Boolean.class);
            log(connected ? "Online" : "Offline");
        }

        @Override
        public void onCancelled(DatabaseError databaseError) {
            log(databaseError.getDetails());
        }
    };
    private DatabaseReference connectedRef;

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_test);
        FirebaseUser user = FirebaseAuth.getInstance().getCurrentUser();
        if (user == null) {
            signIn();
        } else {
            log("User is already logged in");
        }
        connectedRef = FirebaseDatabase.getInstance().getReference(".info/connected");
        connectedRef.addValueEventListener(valueEventListener);
    }

    private void signIn() {
        FirebaseAuth.getInstance().signInAnonymously()
                .addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
                    @Override
                    public void onComplete(@NonNull Task<AuthResult> task) {
                        if (task.isSuccessful()) {
                            FirebaseUser user = FirebaseAuth.getInstance().getCurrentUser();
                            log("Signed in successfully User id " + user.getUid());
                        } else {
                            log("Unable to authenticate app." + task.getException());
                        }
                    }
                });
    }

    @Override
    protected void onResume() {
        super.onResume();
        FirebaseDatabase.getInstance().goOnline();
    }

    @Override
    protected void onStop() {
        super.onStop();
        FirebaseDatabase.getInstance().goOffline();
    }

    private void log(String msg) {
        Log.e(TAG, msg);
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        if (connectedRef != null) {
            connectedRef.removeEventListener(valueEventListener);
        }
    }
}

在logcat下面重复日志，直到应用程序打开。

02-07 09:19:16.677 2435-2635/com.google.android.gms I/AuthChimeraService: Executing send connection operation
02-07 09:19:18.185 4633-4660/com.fire.base.test D/EventRaiser: Raising 1 event(s)
02-07 09:19:18.186 4633-4633/com.fire.base.test D/EventRaiser: Raising /.info/connected: VALUE: true
02-07 09:19:18.186 4633-4633/com.fire.base.test E/TestActivity: Online
02-07 09:19:18.588 4633-4660/com.fire.base.test D/EventRaiser: Raising 1 event(s)
02-07 09:19:18.588 4633-4633/com.fire.base.test D/EventRaiser: Raising /.info/connected: VALUE: false
02-07 09:19:18.588 4633-4633/com.fire.base.test E/TestActivity: Offline
02-07 09:19:19.686 2435-2691/com.google.android.gms E/AsyncOperation: serviceID=16, operation=ValidateAuthServiceOperation
    java.lang.NullPointerException: onPostInitComplete can be called only once per call to getRemoteService
          at kpd.a(:com.google.android.gms:74)
          at kme.a(:com.google.android.gms:987)
          at kna.a(:com.google.android.gms:66)
          at kvb.a(:com.google.android.gms:284)
          at ekn.a(:com.google.android.gms:125)
          at ekn.a(:com.google.android.gms:113)
          at kvi.run(:com.google.android.gms:113)
          at kyl.run(:com.google.android.gms:450)
          at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
          at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
          at lco.run(:com.google.android.gms:17)
          at java.lang.Thread.run(Thread.java:818)

Firebase数据库连接重复连接和断开连接（每秒一次）

0 个答案: