I want to prevent android phone from going to sleep using my code?

Question

I want to prevent android phone from going to sleep using my code? How to do that please help.

Answer 1

You'll probably want to use a wakelock. Example from the docs:

PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE);
 PowerManager.WakeLock wl = pm.newWakeLock(PowerManager.SCREEN_DIM_WAKE_LOCK, "My Tag");
 wl.acquire();
   ..screen will stay on during this section..
 wl.release();

There's also a table on this page that describes the different kinds of wakelocks.

Be aware that some caution needs to be taken when using wakelocks. Ensure that you always release() the lock when you're done with it (or not in the foreground). Otherwise your app can potentially cause some serious battery drain and CPU usage.

Edit to add: You also need to be sure you have the WAKE_LOCK permission set in your Manifest.

Answer 2

what @eldarerathis said is correct in all aspects, the wake lock is the right way of keeping the device from going to sleep.

I don't know waht you app needs to do but it is really important that you think on how architect your app so that you don't force the phone to stay awake for more that you need, or the battery life will suffer enormously.

I would point you to this really good example on how to use AlarmManager to fire events and wake up the phone and (your app) to perform what you need to do and then go to sleep again: Alarm Manager (source: commonsware.com)