CODEWITHSUNDEEP
androidservicescreenstatusreceiver
xampla
xampla

Reputation: 159

Running a receiver even if the app is not open

Well some months ago I learned the basics of android and now I'm triying to practice to remember what I learned. So the problem is that I'm doing an app that when it catches a change in the status of the screen (screen on/screen off) it does something. I want that when the app is not running (becausethe user killed it by pressing the home button or something like that) it still does what I want. I have decided to use receiver but I don't know if it's the correct option.

If the app is minimized it works but the problem whenthe user presses the "recent apps" button and slides the app. Then the receiver doesn't catch anything.

In the manifest I've declared:

<receiver android:name=".MyReceiver" android:enabled="true">
    <intent-filter>
       <action android:name="android.intent.action.SCREEN_ON"/>
       <action android:name="android.intent.action.SCREEN_OFF"/>
    </intent-filter>
</receiver>

My main activity (maybe I have something wrong there):

public class MainActivity extends Activity {

    private MyReceiver myReceiver;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        IntentFilter filter = new IntentFilter(Intent.ACTION_SCREEN_ON);
        filter.addAction(Intent.ACTION_SCREEN_OFF);
        myReceiver = new MyReceiver();
        registerReceiver(myReceiver, filter);
    }


   @Override
   protected void onDestroy() {
       if (myReceiver != null) {
          unregisterReceiver(myReceiver);
          myReceiver = null;
       }
       super.onDestroy();

   }
}

and my receiver:

public class MyReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
       String action = intent.getAction();
       if (action.equals("android.intent.action.SCREEN_OFF")) {
          Log.e("In on receive", "In Method: ACTION_SCREEN_OFF");
          Toast.makeText(context, "DO SOMETHING",Toast.LENGTH_LONG).show();
       }
       else if (action.equals("android.intent.action.SCREEN_ON")) {
          Log.e("In on receive", "In Method: ACTION_SCREEN_ON");
          Toast.makeText(context, "DO SOMETHING2",Toast.LENGTH_LONG).show();
       }
    }
}

Really appreciate if you could take a look :D.
Thank you

Upvotes: 0

Views: 1200

Answers (1)

Henry
Henry

Reputation: 17851

You have registered the receiver in the manifest. So don't register and unregister it in the MainActivity. That's the problem. So once the app is killed, onDestroy() gets called and your receiver is unregistered and will no longer listen.

Declaring the the receiver in the manifest means that your app will always listen to broadcasts. And that's exactly what you want. So remove the register/unregister part from the MainActivity.

UPDATE: It seems that SCREEN_ON and SCREEN_OFF can't be registered via the manifest. This might possibly be for a security reason. So in this case you have to register this via code. But the problem here is that, once you quit the app, onDestroy() is called and you are no longer listening. If you are app really need this feature, you have to create a service and have that run constantly in the the background. You can use that to listen to the broadcast.

Upvotes: 1

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