How do I programmatically “restart” an Android app?

Question

Firstly, I know that one should not really kill/restart an application on Android. In my use case, I want to factory-reset my application in a specific case where a server s

Answer 1

Kotlin version of this answer:

val intent = Intent(this, YourActivity::class.java)
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK or Intent.FLAG_ACTIVITY_CLEAR_TASK)
startActivity(intent)
Runtime.getRuntime().exit(0)

Answer 2

You can use PendingIntent to setup launching your start activity in the future and then close your application

Intent mStartActivity = new Intent(context, StartActivity.class);
int mPendingIntentId = 123456;
PendingIntent mPendingIntent = PendingIntent.getActivity(context, mPendingIntentId,    mStartActivity, PendingIntent.FLAG_CANCEL_CURRENT);
AlarmManager mgr = (AlarmManager)context.getSystemService(Context.ALARM_SERVICE);
mgr.set(AlarmManager.RTC, System.currentTimeMillis() + 100, mPendingIntent);
System.exit(0);

Answer 3

My solution doesn't restart the process/application. It only lets the app "restart" the home activity (and dismiss all other activities). It looks like a restart to users, but the process is the same. I think in some cases people want to achieve this effect, so I just leave it here FYI.

public void restart(){
    Intent intent = new Intent(this, YourHomeActivity.class);
    this.startActivity(intent);
    this.finishAffinity();
}

Answer 4

try this:

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);
}

Answer 5

in MainActivity call restartActivity Method:

public static void restartActivity(Activity mActivity) {
    Intent mIntent = mActivity.getIntent();
    mActivity.finish();
    mActivity.startActivity(mIntent);
}

Answer 6

Jake Wharton recently published his ProcessPhoenix library, which does this in a reliable way. You basically only have to call:

ProcessPhoenix.triggerRebirth(context);

The library will automatically finish the calling activity, kill the application process and restart the default application activity afterwards.