Develop Reference

how to detect if screen is locked if KeyGuard is not set - Android?

I want to know if screen is locked or not, when the SCREEN_OFF is broadcasted while user doesn't set KeyGuard?

1.Take a look in the KeyguardManager documentation here
2.Try this code
public class ScreenReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
if (intent.getAction().equals(Intent.ACTION_SCREEN_OFF)) {
// do whatever you need to do here
//screen is locked & check Keyguard is enabled or Not.
KeyguardManager keyguardManager = (KeyguardManager)getSystemService(Activity.KEYGUARD_SERVICE);
Log.v(TAG,""+keyguardManager.inKeyguardRestrictedInputMode());
} else if (intent.getAction().equals(Intent.ACTION_SCREEN_ON)) {
// and do whatever you need to do here
}
}
}
Hope this helps.
Happy Coding :)

Custom Lock Screen Delay When Wake

I'm trying to make a custom lock screen app, but I'm not sure if I'm going about it the right way. I have a broadcast receiver that listens to when the screen is turned on and starts my lock screen activity. This receiver is registered inside a service, which also disables the default lock screen.
The problem is, there is a slight delay between when the screen is turned on and the lock screen activity shows up. How would I go about doing it so that it shows up right away?
My code for the service:
#Override
public void onCreate() {
super.onCreate();
IntentFilter filter = new IntentFilter(Intent.ACTION_SCREEN_ON);
filter.addAction(Intent.ACTION_SCREEN_OFF);
BroadcastReceiver powerReceiver = new PowerReceiver();
registerReceiver(powerReceiver, filter);
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
KeyguardManager keyguardManager = (KeyguardManager)getSystemService(Service.KEYGUARD_SERVICE);
KeyguardLock lock = keyguardManager.newKeyguardLock(KEYGUARD_SERVICE);
lock.disableKeyguard();
return Service.START_STICKY;
}
#Override
public IBinder onBind(Intent intent) {
return null;
}
and the receiver:
#Override
public void onReceive(Context context, Intent intent) {
if (intent.getAction().equals(Intent.ACTION_SCREEN_ON)) {
Intent showScreen = new Intent(context, LockScreen.class);
showScreen.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(showScreen);
}
}

Turn your app into a home screen replacement app and when the user successfully unlocks the custom lock screen you can take them to the default home app.
You can find more info in this question and these questions.

Problems with android lock in custom lock screen app

I built a custom lock screen app that uses a broadcast receiver and service to listen for when the user turns on or off the screen and from there launch my activity. The activity is supposed to completely replace the lock screen. In order to do this my app is supposed to disable the android stock lock so that my app can function as the new lock screen.
Instead what happens is once the application is first installed the the service first started the application appears to be working. and when the user first turns off the screen of their phone when they turn it back on they are presented with my app running on top and is able to unlock their phone with my app. But then once inside the android OS if the user presses the home button the next time they turn off the screen and turn it back on instead of being brought back to my application they are brought to the stock unlock screen with my application open underneath it, when it should be on top.
Here is my code:
My Service:
public class MyService extends Service {
#Override
public IBinder onBind(Intent intent) {
// TODO Auto-generated method stub
return null;
}
#Override
public void onCreate() {
super.onCreate();
Log.d("MyService","Service STARTED");
final IntentFilter filter = new IntentFilter(Intent.ACTION_SCREEN_ON);
filter.addAction(Intent.ACTION_SCREEN_OFF);
final BroadcastReceiver mReceiver = new ScreenReceiver();
registerReceiver(mReceiver, filter);
}
}
My broadcast receiver:
public class ScreenReceiver extends BroadcastReceiver {
public static ArrayList<String> runningApplications = new ArrayList<String>();
private Context ctext;
public static boolean screenIsLocked;
public static KeyguardManager keyguardManager;
public static KeyguardLock lock;
#Override
public void onReceive(final Context context, final Intent intent) {
ctext = context;
keyguardManager = (KeyguardManager)ctext.getSystemService(Activity.KEYGUARD_SERVICE);
lock = keyguardManager.newKeyguardLock(Context.KEYGUARD_SERVICE);
lock.disableKeyguard();
if (intent.getAction().equals(Intent.ACTION_SCREEN_OFF)) {
screenIsLocked = true;
Log.d("ScreenReceiver", "False");
Intent intenti = new Intent();
intenti.setClass(context, starterActivity.class);
intenti.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
intenti.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(intenti);
} else if (intent.getAction().equals(Intent.ACTION_SCREEN_ON)) {
screenIsLocked = false;
Log.d("ScreenReceiver", "True");
Intent intenti = new Intent();
intenti.setClass(context, starterActivity.class);
intenti.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
intenti.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(intenti);
}
}
My activity that is started is basically empty with just one unlock button that calls finish(); when pressed.

The behavior of keyguard-related logic can vary from device to device. That's because lockscreens are often custom-made by device manufacturers (i.e. not stock), some of them respect the keyguard logic you use, some don't.
Also, afaik the newer way to control keyguard is to use window flags:
// inside activity
getWindow().addFlags(WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD
| WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED);
This will not solve the problem though, devices still have their say about this.
E.g. from my experience, Galaxy Nexus will show your activity's window above keyguard but will not dismiss it (you'd think Google-branded device should respect the flag, eh), so if you hit the back button in your activity - you'll get standard lockscreen --- while HTC One X seems to handle the dismiss part properly: your activity window will cause standard lockscreen to get dismissed as expected.
I found no way to force all devices to behave properly. Android API is not meant to enable you to create custom lock screens (at least not currently). Take a look at the ones in the store - they all have the exact same problem of not being stable enough.
As Dianne Hackborn says in this Google Groups answer, anything you can do in this regard is a hack so expect it to break from time to time.

I tried to compile your code and got the same error you were talking about. I tried to modify it to make it to work and finally got the problem!!!
public class ScreenReceiver extends BroadcastReceiver {
public static ArrayList<String> runningApplications = new ArrayList<String>();
private Context ctext;
public static boolean screenIsLocked;
public static KeyguardManager keyguardManager;
public static KeyguardLock lock;
#Override
public void onReceive(final Context context, final Intent intent) {
ctext = context;
keyguardManager = (KeyguardManager)ctext.getSystemService(Activity.KEYGUARD_SERVICE);
lock = keyguardManager.newKeyguardLock(Context.KEYGUARD_SERVICE);
lock.disableKeyguard();
if (intent.getAction().equals(Intent.ACTION_SCREEN_OFF)) {
screenIsLocked = true;
Log.d("ScreenReceiver", "False");
Intent intenti = new Intent();
intenti.setClass(context, starterActivity.class);
intenti.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
intenti.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(intenti);
} else if (intent.getAction().equals(Intent.ACTION_SCREEN_ON)) {
screenIsLocked = false;
Log.d("ScreenReceiver", "True");
Intent intenti = new Intent();
intenti.setClass(context, starterActivity.class);
intenti.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
intenti.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(intenti);
}
}
With this change to the broadcast receiver class I was able to overcome the problem
Try it and tell me if there is any problem.
EDIT:I think the problem might lie in the finish() method....Android dumps apps when it requires memory...I think finish() might be helping android in trashing the app(and this might be the reason why your problem occurs randomly)

BroadCast Receiver calling intent after some time android

public class myReceiver extends BroadcastReceiver {
public static boolean wasScreenOn = true;
#Override
public void onReceive(final Context context, Intent recievedIntent) {
if (recievedIntent.getAction().equals(Intent.ACTION_SCREEN_OFF)) {
wasScreenOn = false;
Intent intent = new Intent(context,
myActivity.class);
intent.setAction(Intent.ACTION_MAIN);
intent.setFlags(Intent.FLAG_ACTIVITY_NO_USER_ACTION);
intent.setFlags(Intent.FLAG_ACTIVITY_NO_HISTORY);
intent.setFlags(Intent.FLAG_ACTIVITY_NO_ANIMATION);
intent.setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);
context.startActivity(intent
.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK));
} else if (recievedIntent.getAction().equals(Intent.ACTION_SCREEN_ON)) {
wasScreenOn = true;
}
}
}
The activity display after when action screen on is call.
myActivity.class
disableKeyguard using KeyguardManager and start service. In service register the Receiver. Now when user off the device then call ACTION_SCREEN_OFF and when tap home button then call ACTION_SCREEN_ON but the problem is occur when i press home buttom many times.

add one line in manifest in receiver tag
receiver android:name=".MyBoardCast" android:enabled="true"

Android: Wake & unlock phone

I am trying to figure out how to wake and unlock the phone with a service. I have been referring to this post but, I can't figure out why it isn't working. This is the code that I have so far:
public class WakephoneActivity extends Activity {
BroadcastReceiver mReceiver;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
// Log.v(TAG, "Screen OFF onReceive()");
screenOFFHandler.sendEmptyMessageDelayed(0, 2000);
}
};
}
private Handler screenOFFHandler = new Handler() {
#Override
public void handleMessage(Message msg) {
super.handleMessage(msg);
// do something
// wake up phone
// Log.i(TAG, "ake up the phone and disable keyguard");
PowerManager powerManager = (PowerManager) WakephoneActivity.this
.getSystemService(Context.POWER_SERVICE);
long l = SystemClock.uptimeMillis();
powerManager.userActivity(l, false);// false will bring the screen
// back as bright as it was, true - will dim it
}
};
protected void onResume() {
super.onResume();
IntentFilter filter = new IntentFilter(Intent.ACTION_SCREEN_OFF);
registerReceiver(mReceiver, filter);
// Log.i(TAG, "broadcast receiver registered!");
}
}
I have added the code in the manifest as well. Any ideas?

Use this code below in your service.
PowerManager pm = (PowerManager) getApplicationContext().getSystemService(Context.POWER_SERVICE);
mWakeLock = pm.newWakeLock((PowerManager.SCREEN_DIM_WAKE_LOCK | PowerManager.ACQUIRE_CAUSES_WAKEUP), "YourServie");
mWakeLock.acquire();
[...]
mWakeLock.release();
If you want to unlock the screen as well, register a receiver in your service that monitors if the screen is turned on/off and if it is turned off and you want to unlock the phone, start an activity with this code in onCreate:
Window window = getWindow();
window.addFlags(WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD);
this.finish();
return;
I know, this is a rather dirty, but as far as I know, there is no other way of unlocking the lockscreen (and this will only work if there are no passwords etc set, so it must be the normal "slide to unlock" screen).
And don't forget to add android.permission.WAKE_LOCK ;-)
/edit: I just saw you are already using an Activity. If you have one and don't need the service at all, just put this code into the activity.

For the service to be allways active you need to have this permission on manifest:
<uses-permission android:name="android.permission.WAKE_LOCK" />
Another thing you need to do is to adquire a WakeLock. Without it the service will end passed some time. You can do it like this:
getApplicationContext();
PowerManager pm = (PowerManager)getApplicationContext().getSystemService(Context.POWER_SERVICE);
WakeLock wl = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, TAG);
wl.acquire();
You might need to change PowerManager.PARTIAL_WAKE_LOCK to the one that you need. You can see info about that here.

There is WakefulBroadcastReceiver which does this for you. Example use:
import android.content.Context;
import android.content.Intent;
import android.os.SystemClock;
import android.support.v4.content.WakefulBroadcastReceiver;
import android.util.Log;
public class SimpleWakefulReceiver extends WakefulBroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
// This is the Intent to deliver to our service.
Intent service = new Intent(context, SimpleWakefulService.class);
// Start the service, keeping the device awake while it is launching.
Log.i("SimpleWakefulReceiver", "Starting service # " + SystemClock.elapsedRealtime());
startWakefulService(context, service);
}
}
After completing the action in the service, call SimpleWakefulReceiver.completeWakefulIntent(intent) to release the wake lock.
(as #Force already gave you the details about the wakeLock, they need not be repeated here ;-)
Mind that the class is deprecated from api level 26.1.0, reference here