How to detect if my Android Activity was already running when onNewIntent() is called?

Question

I have an Android Activity that sometimes is started by the user and sometimes is started from a service. When started from the service (by sending an Intent that is received by my Activities onNewIntent() callback) I just want it to update its screen if already running but not to start running if it was not already running.

My attempts to achieve this have been arranged around having a boolean set in my Activity during onResume() and cleared during onPause() but I noticed that onPause() is always called before my Activity receives its onNewIntent() and so the value is always false.

For those not familiar with the event sequence it is as follows :

startActivity(myIntent); // Called from service with Intent Extra indicating that fact

onPause(); // Overriden method for my Activity

onNewIntent(Intent myIntent); // Overriden method for my Activity

onResume(); // Overriden method for my Activity

My understanding from reading around is that this behaviour is fixed and intended and there is no way around it. One suggestion I saw was to time the interval between onPause() and onNewIntent() being called and use that as an estimate for whether my Activity had been running immediately before onNewIntent() but I was hoping someone here might know a better way ?

I am actually using Fragments instead of plain Activities but that does not change anything of significance.

Thanks,

`myIntent.putExtra("FROM_SERVICE", true)` in service before starting the Activity then `onNewIntent` `boolean was_from service = myIntent.getBooleanExtra("FROM_SERVICE", false);` also if Activity is not started then first `onCreate` will be called ... — Selvin, Oct 29 '14 at 15:39

score 2 · Accepted Answer · answered Oct 29 '14 at 15:39

If you want just to know if your activity already in foreground then will try this snippet:

class MyActivity extends Activity {
    private boolean isLaunched;

    @Override
    protected void onStart() {
        super.onStart();
        isLaunched = true;
    }

    @Override
    protected void onStop() {
        super.onStop();
        isLaunched = false;
    }

    @Override
    public void onNewIntent(Intent intent) {
        super.onNewIntent(intent);
        if (isLaunched) {
           //todo 
        }
        else
        {
           //somethin here
        }
    }
}

How to detect if my Android Activity was already running when onNewIntent() is called?

1 Answers1