make notification clickable and undestroyable

Question

I tried to create a notification that starts a activity by clicking on it and which you can't swipe away.

NotificationCompat.Builder mBuilder =
                new NotificationCompat.Builder(this)
                .setLargeIcon(BitmapFactory.decodeResource(getResources(), R.drawable.ic_launcher))
                .setSmallIcon(R.drawable.ic_launcher)
                .setContentTitle("DroidSchool")
                .setContentText("DroidSchool l\u00E4uft im Hintergrund...");

        Intent intent = new Intent(this, MainActivity.class);
        PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, intent, Intent.FLAG_FROM_BACKGROUND);

        NotificationManager mNotificationManager =
                (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
        
        int mId = 1234567890;
        mNotificationManager.notify(mId, mBuilder.build());

with the code above the notification gets displayed, but nothing happens when I click on it and you can swipe it away.

Answer 1

To keep the Notification, in that way the user can't click it away in any way, add this flag

Notification mNotification = mBuilder.build();
notification.flags = Notification.FLAG_NO_CLEAR;
mNotificationManager.notify(mId, notification);

To start an Activity you have to use this flag for your Intent

Intent intent = new Intent(this, MainActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, intent, 0);