Firebase数据库一段时间后，ValueEventListener停止工作

Question

我正在使用ValueEventListener来检测firebase中的数据更改。我遇到一种奇怪的情况，当数据成功更改后，我的应用程序能够在应用程序内添加和获取数据，但是即使发生数据更改，我的应用程序也无法从Firebase数据库读取数据（如果已将其安装在其他设备中）

在ValueEventListener停止在其他设备的应用程序上响应之后，我的应用程序在安装的第一天就可以在两种设备上正常工作。

以下是将数据设置为firebase数据库的代码：

public class FirebaseSync extends Service {
FirebaseDatabase fd;
DatabaseReference drr;

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

    fd = FirebaseDatabase.getInstance();
    LocalBroadcastManager.getInstance(FirebaseSync.this).registerReceiver(fReceive, new IntentFilter("FIRE"));
    LocalBroadcastManager.getInstance(FirebaseSync.this).registerReceiver(fCity, new IntentFilter("FCITY"));
    drr = fd.getReference("users").child("key").child("city");
    drr.setValue("--");
}



private BroadcastReceiver fReceive = new BroadcastReceiver() {
    @Override
    public void onReceive(Context context, Intent intent) {

        if (intent != null){

            FireData fireData = new FireData(distance, speed, time, status);
            DatabaseReference dr = fd.getReference("users").child("key");
            dr.setValue(fireData, new DatabaseReference.CompletionListener() {
                @Override
                public void onComplete(@Nullable DatabaseError databaseError, @NonNull DatabaseReference databaseReference) {

                    Log.i("FIREME","Value was set. Error = "+databaseError);                      
                }
            });
        }
    }
};

@Override
public int onStartCommand(Intent intent, int flags, int startId) {
    return START_STICKY;
}

@Override
public void onDestroy() {
    super.onDestroy();
    LocalBroadcastManager.getInstance(FirebaseSync.this).unregisterReceiver(fReceive);
}
@Nullable
@Override
public IBinder onBind(Intent intent) {
    return null;
}
}

从数据库获取数据的代码：

public class Fire extends AppCompatActivity {

FirebaseDatabase database = FirebaseDatabase.getInstance();
DatabaseReference myRef, cref;
boolean connected;
ValueEventListener listener;

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

    connected = false;

    cref = FirebaseDatabase.getInstance().getReference(".info/connected");
    cref.addValueEventListener(new ValueEventListener() {
        @Override
        public void onDataChange(@NonNull DataSnapshot dataSnapshot) {

            if (dataSnapshot.getValue(Boolean.class) != null){
                connected = dataSnapshot.getValue(Boolean.class);

                if (connected){
                    firest.setText("Connected");
                }else {
                    firest.setText("Disconnected");
                }
            }
        }

        @Override
        public void onCancelled(@NonNull DatabaseError databaseError) {
            firest.setText("Listener was cancelled");
        }
    });
}

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

    myRef = database.getReference("users").child("key");

    myRef.keepSynced(true);

    listener = new ValueEventListener() {
        @Override
        public void onDataChange(@NonNull DataSnapshot dataSnapshot) {

            try {
                double di = dataSnapshot.child("dis").getValue(Double.class);
                double sp = dataSnapshot.child("spe").getValue(Double.class);
                String ti = dataSnapshot.child("ti").getValue(String.class);
                boolean st = dataSnapshot.child("sta").getValue(Boolean.class);
                String ci = dataSnapshot.child("cit").getValue(String.class);
                                                    distance.setText(String.format(getResources().getString(R.string.distT), dista, units));
                speed.setText(String.format(getResources().getString(R.string.speedT), speeda));
                time.setText(timea);
                cityText.setText(cityN);


            }catch (NullPointerException e){
                e.printStackTrace();
            }
        }

        @Override
        public void onCancelled(@NonNull DatabaseError databaseError) {

            Toast.makeText(Fire.this, "something wrong happened at read value", Toast.LENGTH_LONG).show();
        }
    };

    myRef.addValueEventListener(listener);        
}

@Override
protected void onStop() {
    super.onStop();

    if (myRef != null && listener != null){
        myRef.removeEventListener(listener);

    }

}
}

我还在firebase控制台上添加了SHA1调试和发布键，但也没有解决。

数据库权限：

  {
  "rules": {
    ".read": true,
    ".write": true
  }
}

App Gradle

    apply plugin: 'com.android.application'
    apply plugin: 'com.google.gms.google-services'

    android {
    compileSdkVersion 27
    defaultConfig {
        applicationId "com.example.adarsh.epoch"
        minSdkVersion 19
        targetSdkVersion 27
        versionCode 1
        versionName "1.0"
         testInstrumentationRunner        "android.support.test.runner.AndroidJUnitRunner"
        multiDexEnabled true
         }
         buildTypes {
         release {
            minifyEnabled false
            proguardFiles   getDefaultProguardFile('proguardandroid.txt'),'proguard-rules.pro'
        }
    }
}

        dependencies {
        implementation fileTree(dir: 'libs', include: ['*.jar'])
        //noinspection GradleCompatible
        implementation 'com.android.support:appcompat-v7:27.1.1'
         implementation 'com.android.support.constraint:constraint-  layout:1.1.3'
          testImplementation 'junit:junit:4.12'
          androidTestImplementation 'com.android.support.test:runner:1.0.2'
           androidTestImplementation   'com.android.support.test.espresso:espresso-core:3.0.2'


            implementation 'com.squareup.okhttp3:okhttp:3.11.0'
            implementation 'com.google.android.gms:play-services-location:16.0.0'
            implementation 'com.google.android.gms:play-services-maps:16.0.0'
            implementation 'com.google.android.gms:play-services-places:16.0.0'
            implementation 'com.google.maps.android:android-maps-utils:0.5'
            implementation 'com.google.code.gson:gson:2.8.5'
             implementation 'com.google.firebase:firebase-core:16.0.5'
            implementation 'com.google.firebase:firebase-database:16.0.4'


}

已经一个星期了，我没有任何解决办法。