when i click notification open another my application

Question

when i'm in my application,i click my application's notification open another my application,there are two same application on screen and btw i'm create notification from intent service

private void sendNotification(String msg, int msgdifferent) {
    NotificationCompat.Builder mBuilder =
            new NotificationCompat.Builder(this)
                    .setSmallIcon(R.drawable.ic_launcher)
                    .setContentTitle("......")
                    .setContentText(msg).setContentInfo(msgdifferent + "");
    Intent resultIntent = new Intent(this, MainActivity.class);
    resultIntent.putExtra("Update", "YES");
    TaskStackBuilder stackBuilder = TaskStackBuilder.create(this);
    stackBuilder.addParentStack(MainActivity.class);
    stackBuilder.addNextIntent(resultIntent);
 PendingIntent resultPendingIntent =
            stackBuilder.getPendingIntent(
                    0,
                    PendingIntent.FLAG_UPDATE_CURRENT
            );
 mBuilder.setContentIntent(resultPendingIntent);
 NotificationManager mNotificationManager =
(NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
mNotificationManager.notify(NOTIFICATION_ID, mBuilder.build());
}

Answer 1

You mean every notification open new activity. So i think you forgot to add this steps as referred from documentation

    android:excludeFromRecents="true"
    android:launchMode="singleTask"
    android:taskAffinity=""

and also set your resultIntent flags like

resultIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);