Android stop activity in onCreate() before calling super.OnCreate()

Question

I am creating an app having a navigation drawer activity with fragments. At every cold start of the app, I am executing some initialization code where I load the following things:

The user session(if the user is logged in or not)
Registering Retrofit services
Getting some data from the server to proceed with startup of the app.

This is the flow of my app when doing a cold start:

Starting MainActivity and verifying the user session.
If the session is valid, then we open the CoreActivity.
If not, then we open the LoginActivity.

When the app is brought to the foreground after some inactivity Android tries to restart the current Activity. This means my initialization code is bypassed and CoreActivity.onCreate() is executed.

All my activities(except MainActivity) are extending the following super activity:

public abstract class MasterActivity extends AppCompatActivity {

@Override
protected final void onCreate(Bundle savedInstanceState) {
    this.supportRequestWindowFeature(Window.FEATURE_INDETERMINATE_PROGRESS);
    if (!CrmContext.getInstance().verifyContextSet(this)) {
        return;
    }
    super.onCreate(savedInstanceState);
    onCreateAfterContext(savedInstanceState);
}

In CrmContext:

public boolean verifyContextSet(final Context context) {
    boolean isContextSet = applicationContext != null;
    if (isContextSet) {
        return true;
    }
    Intent intent = new Intent(context, MainActivity.class);
    intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
    context.startActivity(intent);
    return false;
}

In verifyContextSet() I am doing some checks to be sure that the app has been correctly loaded. If the user session is not properly loaded.

My problem:

If the app is brought to the front the CoreActivity.onCreate() is executed and verifyContextSet() returns false. In this case I want to cancel the creation of CoreActivity and open MainActivity again.

When I do my verifyContextSet() before super.onCreate(), then I get this exception:

android.util.SuperNotCalledException: Activity {nl.realworks.crm/nl.realworks.crm.view.CoreActivity} did not call through to super.onCreate() at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2287) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2391) at android.app.ActivityThread.access$800(ActivityThread.java:151) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1309)

I tried to execute super.onCreate() first, but then the Fragment inside the activity is created first. This means that my Fragment is recreated before my verifyContextSet() is executed.

So, If I try to cancel()/finish() the onCreate() before super.onCreate() has been called, then I get the SuperNotCalledException. If I execute super.onCreate() first, then the Fragment is initialized which is not allowed when verifyContextSet() returns false.

I want to do the following:

Bringing the app to the foreground
Check if the app has been initialized
If not, then finish() the current activity and then restart the app to open MainActivity.

@com2ghz Not calling `super` is a bad approach in my opinion. For me it sounds like you want to check launch mode for your activity. You might want to use`` — longi, Oct 07 '19 at 13:43
I think the issue here is not how to prevent an activity from resuming (it's been outlined) but that this whole idea is incorrectly architected and the OP is now fighting against the Android framework, to accommodate for this requirement. — Martin Marconcini, Oct 10 '19 at 14:53
i kind of solved my problems by not doing anything in my fragment's `onAttach()` callback, because `onAttach()` will be called from `onCreate()` of `FragmentActivity` when restoring from process death — Bhargav, Oct 14 '19 at 12:04

score 1 · Answer 1 · answered Mar 25 '16 at 14:12

1

put your checking/validating code in an Application sub class

public class MyApp extends Application {
//in your oncreate create sessions etc.

now whether MainActivity restarts or not, you have already validated.

Note: Application class' onCreate() is the firs to run before any body.

answered Mar 25 '16 at 14:12

Elltz

10,730
4
31
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I tried this, but it still keeps continuing starting the Activity which was opened previously. How do I prevent that the last Activity is being restarted? – com2ghz Mar 25 '16 at 14:51

Rahul · Answer 2 · 2019-10-10T11:33:16.617

1

What you need to do is to have your onCreate like this

super.onCreate();
if(<activity is not valid>) {
   startAnotherActivity()
   finish()
   return;
}

This will make sure that no other activity lifecycle method is called except onDestroy i.e. onResume, onPause, onStop, onStart.

edited Oct 10 '19 at 11:33

answered Oct 10 '19 at 11:20

Rahul

4,699
5
26
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score 0 · Answer 3 · answered Mar 25 '16 at 13:15

0

I think code should look like that

 @Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    // Your code

}

super.onCreate(savedInstanceState) allways as first line.

answered Mar 25 '16 at 13:15

Jakub S.

5,580
2
42
37

2

When I do this, then the super.onCreate() tries to resume/initialize the Fragment before my `verifyContextSet()` is executed – com2ghz Mar 25 '16 at 13:17
@MikeM. The previous fragment that was opened before the app went to the background. I think the code is irrelevant because I want to do my checks before my fragment get's loaded. – com2ghz Mar 25 '16 at 13:29
I have moved my check to Application.onCreate() but I can't interrupt the execution. It keeps trying to resume the previous Activity – com2ghz Mar 25 '16 at 15:42

nfl-x · Answer 4 · 2019-10-10T14:45:42.130

You can use ViewModel and Observer. Basically your remaining onCreate code will only execute if Observer triggered.


onResume {

    // THIS WILL TRIGGER THE OBSERVER
    viewModel._needVerification.value = true

}

onCreate {

    super.onCreate()

    ... CREATE VIEWMODEL

    // THIS NEEDED TO HANDLE RECREATED ACTIVITY CAUSE BY SCREEN ORIENTATION ETC
    viewModel._verificationFinished.value = false

    viewModel.needVerification.observe(this, Observer{

        if (it == true) {

            verifyContextSet(final Context context) {

                if (isContextSet) {

                    if (viewModel.verificationFinished.value != true) {

                        ... DO REMAINING ONCREATE CODE 

                        viewModel._verificationFinished.value = true

                    }

                } else {

                    Start MainActivity

                }

            }

        }

  })

}

No, no you don't need any of this. – EpicPandaForce Oct 10 '19 at 11:34 — EpicPandaForce, Oct 10 '19 at 11:34
I change the word "need" to "can". – nfl-x Oct 10 '19 at 14:48 — nfl-x, Oct 10 '19 at 14:48

nitinkumarp · Answer 5 · 2019-10-11T06:17:20.173

0

Instead of only returning from onCreate you need to finish the Activity first to stop other initialization callbacks to be triggered.

Just change this code

if (!CrmContext.getInstance().verifyContextSet(this)) {
    return;
}

to this

if (!CrmContext.getInstance().verifyContextSet(this)) {
    finish();
    return;
}

edited Oct 11 '19 at 06:17

answered Oct 10 '19 at 11:56

nitinkumarp

2,120
1
21
30

don't recommend finish without return after it. – Rahul Oct 10 '19 at 13:42

Android stop activity in onCreate() before calling super.OnCreate()

5 Answers5