Cannot open first notification but opens for the rest

I have some kind of SMS application. So everytime the phone received a new message, it should have a notification and upon clicking it, will launch the activity. Right now, when receiving 1 message, it notifies, removes in the status bar and doesn't not launch the activity. But when receiving 2 or more messages, the first notification cannot launched upon clicking while the rest(2nd, 3rd notification...) can. 开发者_StackOverflow中文版Below are my codes.

Intent newIntent = new Intent(context, PreviewActivity.class);
newIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK+0);
newIntent.setAction(strFxPrimaryKey);


Bundle newBundle = intent.getExtras();
newBundle.putInt(GlobalConstants.PRIMARY_ID, Integer.parseInt(strFxPrimaryKey));
newIntent.putExtras(newBundle);

int icon = R.drawable.notification_fx;
CharSequence tickerText = context.getString(R.string.fx_received);
long when = System.currentTimeMillis();

Notification newNotification = new Notification(icon, tickerText, when);
newNotification.flags |= Notification.FLAG_AUTO_CANCEL; //| Notification.FLAG_ONGOING_EVENT;

PendingIntent contentIntent = PendingIntent.getActivity(context, Integer.parseInt(strFxPrimaryKey), newIntent, 0);
newNotification.setLatestEventInfo(context, contentTitle, contentText, contentIntent);

String newNotificationService = Context.NOTIFICATION_SERVICE;
NotificationManager newNotificationManager = (NotificationManager) context.getSystemService(newNotificationService);
newNotificationManager.notify(Integer.parseInt(strFxPrimaryKey), newNotification);

context.startActivity(newIntent);
context.removeStickyBroadcast(intent);

Based on the answers here in the stackoverflow, to create a unique intent, it should have unique action that's why I set the primary key as the action. I also set the request code to primary key to have a unique pending intent. Is there something missing out in my code? Thanks.

EDITED By the way, whenever I remove the context.startActivity(newIntent);, it works right. Can anyone tell me why? Thanks.