请参阅同一项目中的多个firebase数据库

Question

我正在进行一个andoird项目，我需要将我的应用程序连接到2个firebase数据库。问题是，当我在应用程序中午餐时，它会崩溃。我在这里找到了一些建议：Firebase Authentication Limits 但它不起作用。我该怎么办？ thx提前

//FIREBASE_URL is used to store data in a firebase database
private static final String FIREBASE_URL ="https://**********.firebaseio.com/";
//FIREBASE_STRING is used to read data from another firebase database
private static final String FIREBASE_STRING ="https://++++++++++++.firebaseio.com/";
private Firebase firebaseRef;
private Firebase fbRef;

protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    Firebase.setAndroidContext(this);

    firebaseRef = new Firebase(FIREBASE_URL);
    fbRef = new Firebase(FIREBASE_STRING);

}
//The app crashes when this methode
//This methode is used to read data from the second direbase database
public void itineraryListener() {
        fbRef.addValueEventListener(new ValueEventListener() {

            @Override
            public void onDataChange(DataSnapshot snapshot) {

                Toast.makeText(getApplicationContext(), "There are " + snapshot.getChildrenCount() + " locations", Toast.LENGTH_SHORT).show();
                for (DataSnapshot postSnapshot : snapshot.getChildren()) {
                    Itinerary post = postSnapshot.getValue(Itinerary.class);
                }
            @Override
            public void onCancelled(FirebaseError firebaseError) {
                Toast.makeText(getApplicationContext(), "An error occured! " + firebaseError.getMessage(), Toast.LENGTH_SHORT).show();
            }
        });
    }
}

写作方法运作良好，但阅读方法不适用