Android Turn screen Off - android

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.

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.

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"))

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

You can use
getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);

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

Related

Android powermanager wakelock issue

I want to set the wakelock time to the "unlimited" time or at least set the time to xx minutes / hours.
If I try these code :
PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE);
wl = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, "My Tag");
wl.acquire();
It just give me 30 seconds for the wakelock. But if I change my code to wl.acquire(10*60*1000L /10 minutes/); as suggested from Android Studio, it didn't give any change to the wakelock time, any idea of it ?
Make sure you have the Manifest Permissions tag
<uses-permission android:name="android.permission.WAKE_LOCK" />
make sure to call wakeLock.release() when leaving the activity
#Override
protected void onDestroy() {
wakeLock.release();
super.onDestroy();
}
Wakelock doesn't exactly mean it will keep your screen on.
if you want to keep the screen on :
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);
}
then when you want to turn it off :
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O_MR1) {
this.setTurnScreenOn(false);
} else {
final Window window = getWindow();
window.clearFlags(WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON);
}

Proximity sensor with wakelock issue: can't turn on screen again

I've been looking around for the last days and none of the answers to the questions made have helped me and I'm bumping my head with something that perhaps is simple to solve .... I want to work with the proximity sensor and what I'm doing is that if I put the finger on the sensor it turns off the screen and if I remove the finger away it turns back on the screen! I'm sucessfully turning off the screen and I'm getting the "Log.i("info", "trying to turn on!")" message when I remove the finger but somehow the screen doesn't turn on .... I've tried with wakelock (commented) and with flags with no sucess! If I remove the finger the lights on the keypad turn on but the screen won't .. If I press the power button two times it turns on the screen sucessfully! Can anyone give me an help with it? :(
#Override
public void onSensorChanged(SensorEvent event) {
if(event.sensor.getType()==Sensor.TYPE_PROXIMITY){
ProximityReading.setText("\nProximity Sensor Reading:" + String.valueOf(event.values[0]));
}
if(event.values[0] == 0) {
WindowManager.LayoutParams params = getWindow().getAttributes();
getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON);
params.screenBrightness = 0f;
getWindow().setAttributes(params);
} else {
WindowManager.LayoutParams params = getWindow().getAttributes();
params.screenBrightness = 1f;
getWindow().setAttributes(params);
/*powermanager = (PowerManager) getSystemService(Context.POWER_SERVICE);
wakeLock = powermanager.newWakeLock(PowerManager.ACQUIRE_CAUSES_WAKEUP, "TAG");
wakeLock.acquire();
Log.i("info", "trying to turn on!");
}
}
if you want turn screen on,you can use the API such as "TurnScreenOn" in PowerManager,or use ACQUIRE_CAUSES_WAKEUP combined with FULL_WAKE_LOCK
I use the following method to unlock the phone,lighten it up and then reenable the keyguard lock.
public void unlockAndPowerup(){
KeyguardManager km = (KeyguardManager) mContext.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();
wakeLock.release();
kl.reenableKeyguard();
}
Your procedure is wrong. It may work on some devices by chance, but that's not the way to do it.
FLAG_TURN_SCREEN_ON is supposed to be applied on the onCreate method of an activity. You need to modify your app logic.
Your screen off technique is incorrect. You're modifying brightness, that's a hacky way, and may not turn off screen at all, and drain battery.
You need to achieve it via Device Admin permission. That's the official way to do it
Locking sample code
public static void lockNow(Context c) {
DevicePolicyManager dpm = (DevicePolicyManager)c.getSystemService(Context.DEVICE_POLICY_SERVICE);
if(dpm.isAdminActive(new ComponentName(c.getApplicationContext(),DeviceAdmin.class)))
dpm.lockNow();
}
DeviceAdmin.java
import android.app.admin.DeviceAdminReceiver;
public class DeviceAdmin extends DeviceAdminReceiver {
}
In the manifest
<receiver
android:name=".admin.DeviceAdmin"
android:permission="android.permission.BIND_DEVICE_ADMIN" >
<meta-data
android:name="android.app.device_admin"
android:resource="#xml/admin" />
<intent-filter>
<action android:name="android.app.action.DEVICE_ADMIN_ENABLED" />
</intent-filter>
</receiver>
And asking for Device Admin permission
private void askAdminPerm(){
Intent intent = new Intent(DevicePolicyManager.ACTION_ADD_DEVICE_ADMIN);
intent.putExtra(DevicePolicyManager.EXTRA_DEVICE_ADMIN,
new ComponentName(root.getContext(), DeviceAdmin.class));
intent.putExtra(DevicePolicyManager.EXTRA_ADD_EXPLANATION, getString(R.string.lock_msg_big));
startActivity(intent);
}

How to find the screen is locked in android

For my application, I need to know that the screen is locked. How to check this is problematically. I used following flag:
if(WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON != 0){
// some code
}else if((WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED)!= 0){
// some code
}
But this always executing both if and else part... which flag I have to use to check the screen is locked or not?
I'll try to answer this though the question is already old since it is unresolved and could help other googlers. ;)
First you must register a BroadcastReceiver for Intent.ACTION_SCREEN_OFF & Intent.ACTION_SCREEN_ON. Note that this receiver must be registered in codes and will not work when declared in the manifest.
In your broadcast receiver, when you receive Intent.ACTION_SCREEN_ON, you can check if the screen is locked by using the below codes:
KeyguardManager km = (KeyguardManager) getSystemService(Context.KEYGUARD_SERVICE);
boolean locked = km.inKeyguardRestrictedInputMode();
KeyguardManager myKeyManager = (KeyguardManager)getSystemService(Context.KEYGUARD_SERVICE);
if( myKeyManager.inKeyguardRestrictedInputMode()) {
//screen is locked
} else {
//screen is not locked
}
Register a broadcast receiver with action android.intent.action.ACTION_SCREEN_OFF and write your code in onReceive() method of receiver.
If you are using an activity, onPause() will be called when the screen locked and onResume() will be called when the screen unlocked.
In your code you are checking some flags, i don't know where you will do that checking ? is it continuous verification ? If you are using an activity in your app, the above procedure will happen, just check it in Android Developers website.
I guess you may have already found the answer, but if not (and for other developers), you can do it like this:
PowerManager powerManager = (PowerManager) getSystemService(POWER_SERVICE);
boolean isScreenOn = powerManager.isScreenOn();
if (!isScreenOn) {
//Screen is in OFF State
//Code to power on and release lock
KeyguardManager km = (KeyguardManager) this
.getSystemService(Context.KEYGUARD_SERVICE);
final KeyguardManager.KeyguardLock kl = km
.newKeyguardLock("MyKeyguardLock");
kl.disableKeyguard();
PowerManager pm = (PowerManager) this
.getSystemService(Context.POWER_SERVICE);
WakeLock wakeLock = pm.newWakeLock(PowerManager.FULL_WAKE_LOCK
| PowerManager.ACQUIRE_CAUSES_WAKEUP
| PowerManager.ON_AFTER_RELEASE, "MyWakeLock");
wakeLock.acquire();
}
There are broadcasted intents for screen lock & unlock.
Check it like :
if (intent.getAction().equals(Intent.ACTION_SCREEN_OFF)){//LOGIC Here}
Let me know!
Here is what I did:
This handles if the user has unlocked the screen, but not yet entered the home screen or the user's screen is turned off say during a call.
if (Intent.ACTION_SCREEN_ON.equals(pIntent.getAction()) ||
Intent.ACTION_USER_PRESENT.equals(pIntent.getAction())) {
if(mListener!=null) {
KeyguardManager km = (KeyguardManager) context.getSystemService(Context.KEYGUARD_SERVICE);
boolean locked = km.inKeyguardRestrictedInputMode();
Log.v(TAG, ": Phone lock state from KEYGUARD_SERVICE: Current state:" + (locked ? "LOCKED":"UNLOCKED"));
mIsPhoneLocked = locked;
}
}

What should I do as power button do (turn off screen, lock keyboard)?

My goal is make same thing as power button do.
I try PARTIAL_WAKE_LOCK and this is my code..
PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE);
PowerManager.WakeLock wl = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, TAG);
wl.acquire();
after that I open WAKE_LOCK permission in AndroidManifest.xml
<uses-permission android:name="android.permission.WAKE_LOCK" />
But when I launch my application not thing happen.
Do I miss something ?
Thanks
From your question I'm not totally sure whether you:
Try to turn off the device by pressing a button
Want to make sure the device will not go to sleep (as this is what a WakeLock is supposed to help you with). It can't prevent user interaction though (just tested on HTC Desire).
For 1) You can't lock the device or turn it's power off without being signed as a system app, as written here: http://groups.google.com/group/android-developers/browse_thread/thread/36399f15724ac3ae/98d93e53616cf495?show_docid=98d93e53616cf495
For 2) You can prevent the device from sleeping using WakeLock, sample code can read like this:
/**
* Called when the activity is first created.
*/
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE);
wl = pm.newWakeLock(PowerManager.FULL_WAKE_LOCK, TAG);
}
// Call me from a button
public void doLock(View view) {
Log.d(TAG, "Lock");
if (!wl.isHeld()) {
Log.d(TAG, "acquire");
wl.acquire();
} else {
Log.d(TAG, "release");
wl.release();
}
}

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"/>

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