14

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?

Cœur
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CodeMonkey
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  • 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
  • Have you looked into **finishAffinity**? – IgorGanapolsky Jan 03 '18 at 16:16

11 Answers11

21

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.

Dmitry Smolyaninov
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    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
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    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
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    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
19

This works with Android > 10, tested up to Android 13 (preview)

Context ctx = getApplicationContext();
PackageManager pm = ctx.getPackageManager();
Intent intent = pm.getLaunchIntentForPackage(ctx.getPackageName());
Intent mainIntent = Intent.makeRestartActivityTask(intent.getComponent());
ctx.startActivity(mainIntent);
Runtime.getRuntime().exit(0);
grebulon
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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.

Jitesh Mohite
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6

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);
pkgrover
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4

Tray this

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

where finishAffinity() close all other Intents

Abdurahman Popal
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3
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)

Syamsoul Azrien
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3

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.

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().

Ricardo
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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

Vishal Yadav
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Shashwat Gupta
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0

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)
Pranav P
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  • Since Android 10 you can't launch from background, use my method below. See: https://developer.android.com/guide/components/activities/background-starts – grebulon Mar 08 '22 at 09:39
0

This works for me 'Activity.recreate()'

activity?.recreate()
Byron
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  • This method does not result in restarting the application. This simply recreates the activity (the same as configuration change). If the application is not top task activity - you will be left with plenty of elements in the history. – Tomasz Dzieniak May 22 '23 at 20:19