How to change the date on Android Things device?

Question

I\'m using Android Things Developer Preview on Raspberry Pi 3 Model B. Is there any way to set the correct date/time/timezone?

Answer 1

If your app is a system app you can do it like the below:

In your AndroidManifest:

in your activity:

    Calendar c = Calendar.getInstance();
    c.set(2009, 9, 9, 12, 0, 0);
    AlarmManager am = (AlarmManager) this.getSystemService(Context.ALARM_SERVICE);
    am.setTime(c.getTimeInMillis());

This would set the system time to 2009/September/9th, see here for API docs

However to use the SET_TIME permission you need to be a system app.

Unfortunately when using the normal ADB install from Android Studio, it does not install your app as a system app. You would need to do it manually using other ADB commands.

This is possible as you should have root access on any developer device, there is a walk through here explaining how to push your apk as a system app, and then you can set the time as above!

https://android.stackexchange.com/questions/76976/how-to-install-app-as-system-app

or

https://android.stackexchange.com/questions/27/how-do-i-properly-install-a-system-app-given-its-apk

If you do not have the permission (are not a system app) you will see an error like this in your LogCat:

Caused by: java.lang.SecurityException: setTime: Neither user 10026 nor current process has android.permission.SET_TIME.
 at android.os.Parcel.readException(Parcel.java:1683)
 at android.os.Parcel.readException(Parcel.java:1636)
 at android.app.IAlarmManager$Stub$Proxy.setTime(IAlarmManager.java:224)
 at android.app.AlarmManager.setTime(AlarmManager.java:937)
 at com.blundell.MainActivity.onCreate(MainActivity.java:19)