Restarting Android app programmatically

Question

This is a follow up question to this question:

Force application to restart on first activity

I am trying to restart my application from a fragment like that:

    Toast.makeText(getActivity(), "Restarting app", Toast.LENGTH_SHORT).show();
    Intent i = getActivity().getBaseContext().getPackageManager()
.getLaunchIntentForPackage(getActivity().getBaseContext().getPackageName() );
    i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
    i.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
    startActivity(i);
    getActivity().finish();

The code does nothing. The finish() is the only thing working for some reason. If I remove the finish(), nothing happens. Why is that?

https://stackoverflow.com/questions/17294428/how-to-restart-an-application-completely — Amit Vaghela, Sep 06 '17 at 09:04
Possible duplicate of [How do I programmatically "restart" an Android app?](https://stackoverflow.com/questions/6609414/how-do-i-programmatically-restart-an-android-app) — Zoe, Sep 06 '17 at 09:34
Where are you executing this code? Is this in an `Activity`? If so, which one? Please post your manifest. What exactly are you trying to accomplish? — David Wasser, Sep 06 '17 at 11:55

Dmitry Smolyaninov · Accepted Answer · 2017-09-06T15:48:46.297

19

If you just consider to switch to your starting Activity, refer to Ricardo's answer. But this approach won't reset static context of your app and won't rebuild the Application class, so the app won't be really restarted.

If you want to completely restart your app, I can advise more radical way, using PendingIntent.

private void restartApp() {
    Intent intent = new Intent(getApplicationContext(), YourStarterActivity.class);
    int mPendingIntentId = MAGICAL_NUMBER;
    PendingIntent mPendingIntent = PendingIntent.getActivity(getApplicationContext(), mPendingIntentId, intent, PendingIntent.FLAG_CANCEL_CURRENT);
    AlarmManager mgr = (AlarmManager) getApplicationContext().getSystemService(Context.ALARM_SERVICE);
    mgr.set(AlarmManager.RTC, System.currentTimeMillis() + 100, mPendingIntent);
    System.exit(0);
}

P.S. Tried your code in my project - works well with and without finish(). So maybe you have something specific about your Activity or Fragment, you haven't written.

edited Sep 06 '17 at 15:48

answered Sep 06 '17 at 09:20

Dmitry Smolyaninov

1,829
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2

You should consider using **android.os.Process.killProcess(android.os.Process.myPid());** as well – IgorGanapolsky Jan 03 '18 at 14:34
This solution works well with 1 problem. Normally our application exits if the android back button pressed from the main activity. However with thie solution I need to press the back button so many times as many time the application was restarted. Any idea? – Tibor Nagy Dec 14 '18 at 14:11
1

it is not working in Android Q. Can you update the answer? found this https://developer.android.com/preview/privacy/background-activity-starts article but couldn't found a solution. – shobhan Jun 14 '19 at 09:23
1

I confirm, this solution works on Android 9 but does not work on Android 10 (Android Q). I tested on a Pixel XL 4 with no luck... except this way: If I launch the app from the "App Info" page using the "Open" button, then it works, respawning the app as expected! ...but that's a very specific use case! :P – Maestro May 01 '20 at 19:15
Hey, This code is not working in Samusung M51. Android 11. What should I need to taken care of? – Jaimin Modi May 12 '21 at 13:56
@shobhan Hey, This code is not working in Samusung M51. Android 11. What should I need to taken care of? – Jaimin Modi May 12 '21 at 13:57
@Maestro This code is not working in Samusung M51. Android 11. What should I need to taken care of? – Jaimin Modi May 12 '21 at 13:57
@TiborNagy This code is not working in Samusung M51. Android 11. What should I need to taken care of? – Jaimin Modi May 12 '21 at 13:57
@IgorGanapolsky This code is not working in Samusung M51. Android 11. What should I need to taken care of? – Jaimin Modi May 12 '21 at 13:58

score 7 · Answer 2 · answered Sep 06 '17 at 09:12

7

Please refer below code

    Intent intent = new Intent(this, YourHomeActivity.class);
    this.startActivity(intent);
    this.finishAffinity();

It is starting your home activity and dismiss all other activities. It looks like a restart to users, but the process is the same.

answered Sep 06 '17 at 09:12

Jitesh Mohite

15,430
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simple solution works fine thanks – Vivek Apr 07 '21 at 11:40

score 4 · Answer 3 · answered Sep 06 '17 at 09:14

4

try this one

 Intent intent = getActivity().getBaseContext().getPackageManager().getLaunchIntentForPackage(getActivity().getBaseContext().getPackageName() );
                    intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);
                    startActivity(intent);
                    android.os.Process.killProcess(android.os.Process.myPid());
                    System.exit(0);

answered Sep 06 '17 at 09:14

pkgrover

275
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Why do you have these two specific intent flags? – IgorGanapolsky Jan 03 '18 at 14:34
Be careful, https://stackoverflow.com/questions/11035328/why-calling-process-killprocessprocess-mypid-is-a-bad-idea – Photon Point Apr 04 '19 at 05:46

score 3 · Answer 4 · answered Feb 16 '19 at 08:32

3

Tray this

getActivity().finish();
getActivity().startActivity(new Intent(getContext(), Main.class));
getActivity().finishAffinity();

where finishAffinity() close all other Intents

answered Feb 16 '19 at 08:32

Abdurahman Popal

1,562
16
15

score 2 · Answer 5 · answered Sep 06 '17 at 09:06

2

Once you add this FLAGSto the intent

i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
i.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);

and call startActivity(), it will clear all the other activities including the one you call this from, so calling finish() after startActivity() will close the started activity.

Basically, remove getActivity().finish().

answered Sep 06 '17 at 09:06

Ricardo

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I specifically wrote in the question: "If I remove the finish(), nothing happens." – Yonatan Nir Sep 06 '17 at 09:18

score 2 · Answer 6 · answered Sep 06 '17 at 09:07

2

Intent i = getBaseContext().getPackageManager()
             .getLaunchIntentForPackage( getBaseContext().getPackageName() );
i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
finish();
startActivity(i);

You can refer to previous discussion (click here)

answered Sep 06 '17 at 09:07

Syamsoul Azrien

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score 2 · Answer 7 · answered Jun 10 '19 at 12:03

As the accepted answer doesn't seem to work on Android Q anymore due to the new background launch limitations, let me add my own solution:

startActivity(
    Intent(applicationContext, MainActivity::class.java)
)
System.exit(0)

Although it looks strange, it works very reliably for me, as the intent takes longer to fire than the system exit does. Plus, it is fired from the main thread, so Android Q won't complain.

score 0 · Answer 8 · edited Sep 06 '17 at 10:03

0

try using below lines:

Intent i = getBaseContext().getPackageManager()
                .getLaunchIntentForPackage(getBaseContext().getPackageName());
i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(i);
ActivityCompat.finishAfterTransition(YourCurrentActivity.this);

ActivityCompat.finishAfterTransition(YourCurrentActivity.this); this line clear the instance after creating another activity

edited Sep 06 '17 at 10:03

Vishal Yadav

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answered Sep 06 '17 at 09:07

Shashwat Gupta

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The method finishAfterTransition(Activity) is undefined for the type ActivityCompat – Yonatan Nir Sep 06 '17 at 09:15

score 0 · Answer 9 · answered Aug 07 '19 at 11:39

Add this code as per your activity and your app will restart. This code is in kotlin.

val intent = Intent(baseContext, MainActivity::class.java)
val pendingIntentId = 101
val pendingIntent = PendingIntent.getActivity(this, pendingIntentId,intent, PendingIntent.FLAG_CANCEL_CURRENT)
val alarmManager = (this.getSystemService(Context.ALARM_SERVICE)) as AlarmManager
alarmManager.set(AlarmManager.RTC, System.currentTimeMillis() + 100, pendingIntent)
exitProcess(0)

Restarting Android app programmatically

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