Develop Reference

Android Device screen not turning off

I started songs on one of the music apps, on my android device.
Although I can see only partial wake_locks being acquired, still device display doesn't turn off even after screen timeout.
I wonder what is keeping the device screen on.
Can someone suggest where to look for probable cause.
Thanks!

PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE);
PowerManager.WakeLock wakeLock = pm.newWakeLock(
pm.SCREEN_DIM_WAKE_LOCK, "My wakelook");
// This will make the screen and power stay on
// This will release the wakelook after 1000 ms
wakeLock.acquire(1000);
// Alternative you can request and / or release the wakelook via:
// wakeLock.acquire(); wakeLock.release();
I used this code and works fine to me.

Detect phone movement when screen is off

I am developing an application which should detect user movement and when he stops for more than 5 minutes it should sound an alarm. I was able to detect movement with accelerometer but the problem is it doesnt work when the screen is off. I have also tried using partial wakeLock. Re-registering accelerometer doesnt work either (this should be workaround for motorola devices).
Maybe I can do this using GPS and sound an alarm when GPS speed is less than 1m/s for more than 5 minutes but I am not sure if I will receive GPS updates when screen is off.
So I need a solution that will detect user movement even is screen is off on most devices. Any ideas on how to acomplish this?
Thanks in forward

You should acquire a partial wake lock for this kind of operation. Use the PowerManager class.
Something like this:
PowerManager pm = (PowerManager)getSystemService(POWER_SERVICE);
PowerManager.WakeLock lock = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, "SensorRead");
lock.acquire();
You need also this permission in the AndroidManifest.xml:
<uses-permission android:name="android.permission.WAKE_LOCK" />
Is recommendable using lock.release(); when you're done your work.
EDIT:
Also, this article could be useful for you.

partial wake lock this is what you need to access while your screen is off.
private PowerManager.WakeLock mWakeLock;
PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE);
mWakeLock = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, "My Tag");
mWakeLock.acquire();
And after you're done, just release the lock:
mWakeLock.release();
If you obtain accelerometer data in a Service, you could simply acquire lock in it's onCreate() and release in onDestroy().

Android - Disable proximity sensor in my app

I'm working on an app that allows the user to start a phone call from the app itself and once the call was initiated, the user can get back to the app to do some UI actions.
My current problem is that once the call started the proximity sensor was enabled which makes it almost impossible to work with the app (depends on the sensitivity of the sensor - per device).
Is there anyway to control the sensor?
For example, I would like to disable the sensor once my activity is visible and re-enable it once invisible.
Thanks,
Lior.

Try to set WakeLock in your application code...like below....
PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE);
PowerManager.WakeLock wl = pm.newWakeLock( PowerManager.FULL_WAKE_LOCK, "FullWakeLock" );
Hope it will help you...

Keep My App alive - Android

I'm trying to make an App on Android 2.2 that has to run whether the screen is on or off.
I tried realizing it via a Service, but when my phone turns the screen off the service stopps working and I don't understand why.
In my Application I use
startService(new Intent(this, MyService.class));
when the User presses a button
and
Notification notification = new Notification();
startForeground(1, notification);
in the onCreate-Method of the Service class
(I tried it within the onStart() Method, too)
(I also could not find out what the id-field of startForeground() expects so I used the 1)
The service then should start an infinite vibration pattern of the phone so I know whether it is running or not.
But when I turn off the screen, the phone stops vibration immediately
Please help me. I don't know how I can fix that (and google was not a big help)
Sincerely
zed

Android devices go to a sleep mode when idle (e.g. when the screen is off), in order to conserve the battery.
To keep your service running you need to aquire a WakeLock. There are plenty of tutorials how to use it, like this one.
Note that having a service running all the time will drain your battery. Also make absolutely sure to release the wakelock when not needed, otherwise you're phone will always be awake.

Try returning 'START_STICKY' from 'onStartCommand() '. This will keep the service running, restarting it if necessary, without keeping the screen on.
Have a look at http://developer.android.com/reference/android/app/Service.html#START_STICKY

try this
KeyguardManager km = (KeyguardManager) getSystemService(Context.KEYGUARD_SERVICE);
final KeyguardManager.KeyguardLock kl = km .newKeyguardLock("MyKeyguardLock");
kl.disableKeyguard();
PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE);
WakeLock wakeLock = pm.newWakeLock(PowerManager.FULL_WAKE_LOCK
| PowerManager.ACQUIRE_CAUSES_WAKEUP
| PowerManager.ON_AFTER_RELEASE, "MyWakeLock");
wakeLock.acquire();
and in manifest file
<uses-permission android:name="android.permission.DISABLE_KEYGUARD" />
<uses-permission android:name="android.permission.WAKE_LOCK" />
so when your notification or alarm manager service running, screen will light on and the keyguard will unlock.I wish it works for who has this problem too.

Preventing application/screen timeout Android

I have an Android (version 1.5) application which needs to be constantly running when a button is pressed. So, when a Button is pressed I would like the phone to remain on and not want the screen or CPU to time-out.
When another Button is pressed I would like the phone to be back to normal and time-out as per user settings.

Update: As suggested by Steve Pomeroy, this might be a better way to do it.
You can use a WakeLock that requires the following permission:
<uses-permission android:name="android.permission.WAKE_LOCK" />
Here is how you aquire and release a WakeLock:
PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE);
PowerManager.WakeLock wl = pm.newWakeLock(PowerManager.FULL_WAKE_LOCK, "My Tag");
wl.acquire();
// wake locked...
wl.release();
Depending on your requirements you might be able to use a different type of WakeLock.

Instead of using a wakelock, you should consider the solution proposed here: Force Screen On
It is much easier to use and doesn't have the potential of accidentally wasting the user's batteries.