Launch Activity from Service without Notification

I am using the benconding Alarmmanager Plugin to set an alarm on Android. The alarm triggers a service. When the service launches a Notification, I can click the Notification and start the main Activity, which is responsible for setting the alarm in the first place. This works as expected.

Here ist the code from my alarmService.js

var service = Ti.Android.currentService;
var serviceIntent = service.getIntent();
Ti.Android.stopService (serviceIntent);
 
var activity = Ti.Android.currentActivity;
var intent = Ti.Android.createIntent({
    action : Ti.Android.ACTION_MAIN,
    className : 'com.myApp.alarmtest.AlarmTestActivity',
    flags : Ti.Android.FLAG_ACTIVITY_RESET_TASK_IF_NEEDED | Ti.Android.FLAG_ACTIVITY_SINGLE_TOP
});
intent.addCategory(Titanium.Android.CATEGORY_LAUNCHER);
 
var pending  = Ti.Android.createPendingIntent({
    activity : activity,
    intent : intent,
    type : Ti.Android.PENDING_INTENT_FOR_ACTIVITY,
    flags : Ti.Android.FLAG_ACTIVITY_NO_HISTORY
});
 
var cfg = {
    contentIntent : pending,
    contentTitle : 'Alarm!',
    contentText : 'Jupiiee',
    tickerText : 'Juppiee',
    when : new Date().getTime(),
    icon : Ti.App.Android.R.drawable.appicon,
    flags : Titanium.Android.FLAG_AUTO_CANCEL | Titanium.Android.FLAG_SHOW_LIGHTS | Titanium.Android.FLAG_INSISTENT
};
 
var notification = Ti.Android.createNotification(cfg);
 
Ti.Android.NotificationManager.notify (1, notification);
 
Ti.Media.vibrate([0,100,200,100,100,100,100,100,200,100,500,100,225, 100]);

But I would like to start the Activity without the Notification. When the alarm starts the service, the service should launch/relaunch the Activity without user interaction.

My alarm is triggered at the right time, the vibration works fine, the debugger tells me, that the activity is started, but nothing changes on my phone (I am testing on device). I do not get any errors, but the app is not started or put into the foreground. [Edit] Before the alarm starts I go to the home-screen.

Here ist the changed code of my alarmService.js

var service = Ti.Android.currentService;
var serviceIntent = service.getIntent();
Ti.Android.stopService (serviceIntent);
 
var activity = Ti.Android.currentActivity;
var intent = Ti.Android.createIntent({
    action : Ti.Android.ACTION_MAIN,
    className : 'com.myApp.alarmtest.AlarmTestActivity',
    flags : Ti.Android.FLAG_ACTIVITY_NEW_TASK | Ti.Android.FLAG_ACTIVITY_SINGLE_TOP
});
intent.addCategory(Titanium.Android.CATEGORY_LAUNCHER);
 
Ti.Android.currentActivity.startActivity(intent);
 
Ti.Media.vibrate([0,100,200,100,100,100,100,100,200,100,500,100,225, 100]);

Is this even possible to do? I spent the last 4 days reading through the docs and stackoverflow and many threads, but most of them concern themeselves with starting an activity from Notifications. Also I am new to App Developement although I am a proficient Web-Developer.

Thank you for your time and input!