在新子项上生成通知的服务已添加到火力数据库

Question

我正在尝试首次构建聊天应用程序，我想在将新消息添加到数据库时（使用Android Studio）通知用户。

因此，与其使用云功能（因为它是如此困难），不如说我将使用在后台运行并触发对Firebase数据库的onChildadded（）通知的服务。

如何编写一个服务类，该服务类将从数据库中获取引用并触发通知？

我正在使用

字符串NOTIFICATION_CHANNEL_ID =“ my_channel_id_01”;

private FirebaseDatabase database;
private DatabaseReference mFirebaseReference;
private ChildEventListener mChildEventListener;
private FirebaseAuth mAuth;
private FirebaseAuth.AuthStateListener mAuthStateListener;
private FirebaseStorage mFirebaseStorage;
private StorageReference mChatPhotosReference;
private NotificationManager mNotificationManager ;
public  NotificationCompat.Builder mBuilder ;
int some = 0;

public PushNotification() {

    database = FirebaseDatabase.getInstance();
    mAuth = FirebaseAuth.getInstance();
    mFirebaseStorage = FirebaseStorage.getInstance();
    mFirebaseReference = database.getReference().child("list");

    attachDatabaseReadListener();

}

protected void attachDatabaseReadListener() {

    if (mChildEventListener == null) {
        mChildEventListener = new ChildEventListener() {
            @Override
            public void onChildAdded(DataSnapshot dataSnapshot, String s) {

                Intent intent = new Intent(getBaseContext(), MainActivity.class);
                intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
                PendingIntent pendingIntent = PendingIntent.getActivity(getBaseContext(), 0, intent,
                        PendingIntent.FLAG_ONE_SHOT);

                NotificationManager notificationManager =
                        (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);


                NotificationCompat.Builder mnotificationBuilder = new NotificationCompat.Builder(getBaseContext())
                        .setSmallIcon(R.mipmap.ic_launcher)
                        .setContentTitle("new Notification")
                        .setContentText("notification example")
                        .setPriority(NotificationCompat.PRIORITY_DEFAULT)
                        .setContentIntent(pendingIntent)
                        .setAutoCancel(true)
                        .setOnlyAlertOnce(true)
                        .setSound(RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION));

                notificationManager.notify(0, mnotificationBuilder.build());
            }

            @Override
            public void onChildChanged(DataSnapshot dataSnapshot, String s) {
                mNotificationManager.notify(some, mBuilder.build());
            }

            @Override
            public void onChildRemoved(DataSnapshot dataSnapshot) {
                mNotificationManager.notify(some, mBuilder.build());
            }

            @Override
            public void onChildMoved(DataSnapshot dataSnapshot, String s) {
                mNotificationManager.notify(some, mBuilder.build());
            }

            @Override
            public void onCancelled(DatabaseError databaseError) {
            }
        };

        mFirebaseReference.addChildEventListener(mChildEventListener);
    }

}


@Override
public IBinder onBind(Intent intent) {
    // TODO: Return the communication channel to the service.
    throw new UnsupportedOperationException("Not yet implemented");
}

}