How to force resume an Activity paused from stack by name

Question

i'm using a Service to call my Activity by name as follows:

Intent i = new Intent();
i.setComponent(new ComponentName("com.packagename", "com.packagename.activities.Intro"));
i.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
i.putExtra("fromservice", true);
startActivity(i);

And it works well, but i'd like to show my "Intro" Activity resuming it, not starting it (no need to instance onCreate again), so, how could i do in this way?

Thanks in advance!!