Develop Reference

How to Unlock Android Screen From inside Service (Marshmallow)?

I am developing an app to schedule whattsapp messages. Curruntly i want to unlock screen and start whattsapp intent and send msg inside my service . I searched here and tried following solution. but both are depreciated. Method 1 (depreciated) `
Window window = this.getWindow();
window.addFlags(LayoutParams.FLAG_DISMISS_KEYGUARD);
window.addFlags(LayoutParams.FLAG_SHOW_WHEN_LOCKED);
window.addFlags(LayoutParams.FLAG_TURN_SCREEN_ON);
Method 2 (depreciated)
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();
I tried both methods but none seems to work. both Root and Noroot methods will work
Please Help

After use PowerManager my device never goes to sleep mode anymore

I´m doing an app and I´m testing it on devices Samsung galaxy Y (Android 2.3.6) and Engel tablet 7" (Android 4.0.x).
In my app´s code I´m using this snippet in order to wake up the devices(when they are in sleep mode) and works well , but now my problem is that after wake up they never go to sleep mode anymore, only they go if I press the hardware button.
Anyone know how I can set the default energy settings after use PowerManager ?.
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();

Try this:
void wakeUpGirls() {
if (wakeLock != null) {
wakeLock.release();
}
KeyguardManager km = (KeyguardManager) getSystemService(Context.KEYGUARD_SERVICE);
KeyguardLock keyguardLock = km.newKeyguardLock("TAG");
getWindow().addFlags(WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD);
keyguardLock.disableKeyguard();
PowerManager pm = (PowerManager)getSystemService(Context.POWER_SERVICE);
wakeLock = pm.newWakeLock(PowerManager.FULL_WAKE_LOCK
| PowerManager.ACQUIRE_CAUSES_WAKEUP
| PowerManager.ON_AFTER_RELEASE
| PowerManager.SCREEN_BRIGHT_WAKE_LOCK, "MyWakeLock");
wakeLock.acquire();
}
void sleepGirls() {
if (wakeLock != null) {
wakeLock.release();
wakeLock = null;
}
}

Use this one it works for me
PowerManager powermanager= ((PowerManager)getSystemService(Context.POWER_SERVICE));
WakeLock wakeLock = powermanager.newWakeLock(PowerManager.SCREEN_BRIGHT_WAKE_LOCK | PowerManager.ACQUIRE_CAUSES_WAKEUP, "tag");
wakeLock.acquire(9000);
wakeLock.release
KeyguardManager km =(KeyguardManager)getSystemService(KEYGUARD_SERVICE);
k1 = km.newKeyguardLock("IN");
k1.disableKeyguard();

Android: Which events do wakeup a device

I have written an android application and now there is a problem.
If my application is running and I power off my device, then sometimes it just wakes up after about 8 seconds and then the screen is on and it shows my application again.
My question is:
Which events or processing constraints (like handling broadcast intents) do wakeup a device?
Edit: Will an alarm with RCT_WAKEUP turn on the device screen?
Thanks in advance!

The AlarmManager won't actually turn the screen on for you. You can use a wakelock instead.
PowerManager.WakeLock wakelock;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
.........
PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE);
wakelock = pm.newWakeLock(PowerManager.FULL_WAKE_LOCK
| PowerManager.ACQUIRE_CAUSES_WAKEUP | PowerManager.SCREEN_BRIGHT_WAKE_LOCK, "AlarmReceiver");
wakelock.acquire();
}
When you're done with the activity just be sure to release the wakelock:
#Override
protected void onStop() {
super.onStop();
wakelock.release();
}
You also need to add the wake lock permission in your manifest file:
<uses-permission android:name="android.permission.WAKE_LOCK"/>
Alternatively, if you don't want to have to include this extra permission you can use the following code in your activity instead of using a wakelock:
this.getWindow().addFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN |
WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD |
WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED |
WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON |
WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);

Android Trun on backlight

I need to turn on screen back-light and keyboard backlight when my application receive notification. I have tried with PowerManager It it wasn't successful.
Is there any way to turn on screen and keyboard backlights?
Thank You.

I have solved this issue.
private void backlightON(Context context){
PowerManager pm = (PowerManager) context.getSystemService(Context.POWER_SERVICE);
PowerManager.WakeLock wakeLock = pm.newWakeLock(PowerManager.FULL_WAKE_LOCK | PowerManager.ACQUIRE_CAUSES_WAKEUP, "MessageReader");
wakeLock.acquire();
}

Turning on screen programmatically

I would like to unlock screen and switching it on to show a popup on an event trigger. I am able to unlock the screen using
newKeyguardLock = km.newKeyguardLock(HANDSFREE);
newKeyguardLock.disableKeyguard();
on KeyGuardService but I cannot turn on the screen. I am using
wl = pm.newWakeLock(PowerManager.SCREEN_BRIGHT_WAKE_LOCK, HANDSFREE);
wl.acquire();
but with no success. The screen still remains off.
How can I achieve this?

Note from author: I wrote this back in 2012. I don't know if it works anymore. Be sure to check out the other more recent answers.
Amir's answer got me close, but you need the ACQUIRE_CAUSES_WAKEUP flag at least (Building against Android 2.3.3).
WakeLock screenLock = ((PowerManager)getSystemService(POWER_SERVICE)).newWakeLock(
PowerManager.SCREEN_BRIGHT_WAKE_LOCK | PowerManager.ACQUIRE_CAUSES_WAKEUP, "TAG");
screenLock.acquire();
//later
screenLock.release();

This is very popular question but the accepted answer now is outdated.
Below is latest way to Turn On Screen OR wake up your device screen from an activity:
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O_MR1) {
this.setTurnScreenOn(true);
} else {
final Window window = getWindow();
window.addFlags(WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON);
}
Use WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON but FLAG_TURN_SCREEN_ON flag has been deprecated in API level 27 so you can use Activity.setTurnScreenOn(true) from API level 27 onward.

In your main activity's OnCreate() write following code:
((PowerManager)getSystemService(POWER_SERVICE)).newWakeLock(PowerManager.SCREEN_DIM_WAKE_LOCK, "TAG").acquire();
It causes the device to wake up.
Do not forget disableKeyguard() to unlock the device...

undefined's answer with NullPointer check and set timeout :
private void turnOnScreen() {
PowerManager.WakeLock screenLock = null;
if ((getSystemService(POWER_SERVICE)) != null) {
screenLock = ((PowerManager)getSystemService(POWER_SERVICE)).newWakeLock(
PowerManager.SCREEN_BRIGHT_WAKE_LOCK | PowerManager.ACQUIRE_CAUSES_WAKEUP, "TAG");
screenLock.acquire(10*60*1000L /*10 minutes*/);
screenLock.release();
}
}

This is how you can do it:
PowerManager powerManager = (PowerManager) context.getSystemService(context.POWER_SERVICE);
PowerManager.WakeLock wakeLock = powerManager.newWakeLock(PowerManager.FULL_WAKE_LOCK |
PowerManager.ACQUIRE_CAUSES_WAKEUP |
PowerManager.ON_AFTER_RELEASE, "appname::WakeLock");
//acquire will turn on the display
wakeLock.acquire();
make sure to set permission in the manifest :
<uses-permission android:name="android.permission.WAKE_LOCK"/>