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How can I tell if the current Activity's OnResume has fired because the Application is resuming after the screen was unlocked rather than simply because it was temporarily in the background?

Pat Long - Munkii Yebee
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2 Answers2

2

You can use a BroadcastReceiver to listen to the screen unlock Intent:

Implement this BroadcastReceiver:

public class UnlockBroadcastReceiver extends BroadcastReceiver {

    @Override
    public void onReceive(Context arg0, Intent intent) {
        final String action = intent.getAction();
        if(Intent.ACTION_USER_PRESENT.equals(action)){
            // Screen unlocked (Keyguard is gone)
        }
    }
}

And then you can register and unregister the BroadcastReceiver in onResume() and onPause() like this:

private final UnlockBroadcastReceiver unlockReceiver = new UnlockBroadcastReceiver();

@Override
protected void onResume() {
    super.onResume();

    IntentFilter filter = new IntentFilter(Intent.ACTION_USER_PRESENT);
    registerReceiver(unlockReceiver, filter);
}

@Override
protected void onPause() {
    super.onPause();

    unregisterReceiver(unlockReceiver);
}

You can alternatively also register it in the manifest, but that does NOT work most of the time.

<receiver android:name="path.to.UnlockBroadcastReceiver">
    <intent-filter android:enabled="true" android:exported="false">
            <action android:name="android.intent.action.USER_PRESENT" />
        </intent-filter>
</receiver>
Xaver Kapeller
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  • I did indeed need to a BroadcastReceiver and USER_PRESENT action but the only way to get it to fire is to register the receiver in code. Xaver if you update your answer to refer to this answer (http://stackoverflow.com/a/1588267/63286) around code registration I will then mark yours as MY answer – Pat Long - Munkii Yebee Jul 21 '14 at 17:06
  • I updated my answer. Could you test if it is working with the changes I made to the manifest? I am currently not in front of my computer and cannot test it myself. – Xaver Kapeller Jul 21 '14 at 17:12
  • I had already tried those two attributes. Did you see what @CommonsWare said? – Pat Long - Munkii Yebee Jul 21 '14 at 17:13
  • Yes I saw, it seems such a `BroadcastReceiver` can only be registered in code. But I will test this more thoroughly when I find the time. – Xaver Kapeller Jul 21 '14 at 17:15
  • Xaver did you "test thoroughly"? I want to mark your answer as "the one" but it needs to have the code regsitration in it IMHO – Pat Long - Munkii Yebee Jul 31 '14 at 09:00
  • Yes I tested it, and I found out that registering the `BroadcastReceiver` in the manifest actually works on some devices with specific Android versions. But I have still no idea why it works on those devices and not on the others. – Xaver Kapeller Jul 31 '14 at 09:06
0

In Activity or Service:

try {
                  IntentFilter filter = new IntentFilter(Intent.ACTION_SCREEN_ON);

                  filter.addAction(Intent.ACTION_SCREEN_OFF);
    filter.addAction(Intent.ACTION_USER_PRESENT);

                  BroadcastReceiver mReceiver = new receiverScreen();

                  registerReceiver(mReceiver, filter);
             } catch (Exception e) {

             }

receiver code where System inform you if Screen on/off happen:

public class receiverScreen extends BroadcastReceiver {

     @Override
     public void onReceive(Context context, Intent intent) {

         if (intent.getAction().equals(Intent.ACTION_SCREEN_ON)){

         }
        if (intent.getAction().equals(Intent.ACTION_SCREEN_OFF)){

         }
if (intent.getAction().equals(Intent.ACTION_USER_PRESENT)){

         }
     }

    }

If it IS locked, you can just write to a SharedPreference. Then on your activity's onResume(), you can check for the value of the sharedPreference

In your manifest.xml 

   <receiver android:name="receiverScreen">
        <intent-filter> 
            <action android:name="android.intent.action.SCREEN_ON" />
            <action android:name="android.intent.action.SCREEN_OFF" />
<action android:name="android.Intent.action.USER_PRESENT" />
        </intent-filter> 
    </receiver>
harveyslash
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    That is a bad solution. It won't actually work as the OP wants to. – Xaver Kapeller Jul 21 '14 at 12:54
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    @harvey_slash - Please note the action should be - `android.intent.action.USER_PRESENT` in manifest file. The action `"android.Intent.ACTION_USER_PRESENT"` is incorrect. – sjain Jul 21 '14 at 12:59