android AlarmManager not waking phone up

Question

I want an activity to be displayed at a certain time. For this, I am using AlarmManager. It works fine when the device is awake, but it doesn\'t wake it up if it\'s asleep.<

Answer 1

Most likely, the alarm is waking up the device. However, AlarmManager broadcasts won't turn the screen on, and the device may well fall back asleep before your activity starts up.

You will need to acquire a WakeLock in onReceive() before calling startActivity(), and release that WakeLock after the user responds to your activity.