Android Turn screen Off

Question

I can't turn off the screen using this code. I used PowerManager and wl.release() method, but it doesn't work. Can somebody show me an example?

  PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE); 
   wl = pm.newWakeLock(PowerManager.FULL_WAKE_LOCK, "DoNotDimScreen");

This is part of my function:

  stateString = "nextone";
  if(stateString=="nextone"){        
  wl.release();
   }

I also added permission in the manifest but no result.

Well, your comparison with stateString will never be true. To compare strings in java you should use `stateString.equals("nextone")` instead. — Eloff, Sep 01 '11 at 07:09

score 2 · Answer 1 · edited May 23 '17 at 12:14

2

I found the answer over here on stack overflow: Turn off screen on Android

Copied from there:

WindowManager.LayoutParams params = getWindow().getAttributes(); 
params.flags |= LayoutParams.FLAG_KEEP_SCREEN_ON; 
params.screenBrightness = 0; 
getWindow().setAttributes(params);

I tried this out and it seems to work.

edited May 23 '17 at 12:14

Community

1
1

answered Aug 30 '11 at 23:54

Gdalya

385
3
17

this solve the problem: getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON); – ademar111190 Jul 02 '12 at 17:52
this code works fine to turn off screen,but how to turn it on back ? – Uniruddh Jun 10 '14 at 13:10
Setting params.screenBrightness to a value between 0 and 1 gives you brightness between 0% and 100%. Setting it to a negative value gives you auto brightness. I forget where I 1st saw this, but I use it all the time. – Gdalya Jun 11 '14 at 13:39

score 0 · Answer 2 · edited Aug 12 '12 at 01:33

0

You can use

getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);

edited Aug 12 '12 at 01:33

skynet

9,898
5
43
52

answered Jul 02 '12 at 17:53

ademar111190

14,215
14
85
114

score 0 · Answer 3 · edited May 23 '17 at 12:22

0

try 
{
    Settings.System.putInt(getContentResolver(), Settings.System.SCREEN_OFF_TIMEOUT, 1000*15);
} 
catch (NumberFormatException e) 
{
    Log.e("aa", "could not persist screen timeout setting", e);
}

How to detect switching between user and device

edited May 23 '17 at 12:22

Community

1
1

answered Oct 29 '13 at 09:12

pengwang

19,536
34
119
168

score 0 · Answer 4 · answered Aug 25 '11 at 23:26

If you don't use a permission, the program will crash with a SecurityException when it tries to lock, so that isn't the problem. The correct method is: (obtains WakeLock on start, gives it up when the application loses focus (onPause)

//declared globally so both functions can access this
public PowerManager.WakeLock wl;

///////////onCreate
//stop phone from sleeping
PowerManager powman = (PowerManager) getSystemService(Context.POWER_SERVICE);
wl = powman.newWakeLock(PowerManager.SCREEN_BRIGHT_WAKE_LOCK, "NameOfLock");
wl.acquire();

///////////onPause
wl.release();

//////////for completion's sake, onResume
if(!wl.isHeld()){
    wl.acquire();
}

However, your problem is actually in this check

if(stateString=="nextone")

This should be if(stateString.equals("nextone"))

score 0 · Answer 5 · edited May 23 '17 at 11:58

0

please check this link before proceeding with wake lock. if it does not solve your problem then you can proceed with wake lock.

Force Screen On

edited May 23 '17 at 11:58

Community

1
1

answered Aug 26 '11 at 00:52

Samuel

9,883
5
45
57

Android Turn screen Off

5 Answers5