Unable to Keep Screen from Sleeping in Android 4.2

Question

I have a simple battery test app I wrote for Android and have used for several versions now successfully. It works fine in Android 4.1 The app simply launches the chrome browser to a different web site, logs the time to a database, waits 60 seconds and does it all over again.

Now, in Android 4.2, the screen turns off and system goes to sleep despite the fact that I have a wakelock and have set screen timeout to never using settings. What's most annoying is it turns off at an indeterminate time, not a fixed time after starting the test. Any idea what I need to do?

Here's the wakelock code I call in the service that launches the browser over and over again.

    super.onCreate();
    // Wakelock
    PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE);
    PowerManager.WakeLock wl = pm.newWakeLock(PowerManager.FULL_WAKE_LOCK, "My Tag");
    wl.acquire();

I also put this in the layout file

android:keepScreenOn="true"

However, the app's screen itself isn't visible throughout the test as Chrome is always the foreground window and the browser launcher is a service and the wakelock is in the service.

Any idea how to keep the screen from timing out? Nothing seems to work.

Answer 1

Just add following line to your XML file......

android:keepScreenOn="true"

:)

Answer 2

I would guess that Android is killing your service and causing your wakelock to be released. Try making your service run in the foreground (with startForeground() ) and see if that helps.