Shared Preferences get lost after shutting down device or killing the app

Question

there are lots of questions out there related to shared preferences and the alternatives. My problem: when I shut down the device or kill the app, the shared preferences get

Answer 1

I've figured out a solution that works both, on my Acer and on my XOOM device: you have to call clear() on the editor before committing new data:

public void saveCollection(Context context){
    SharedPreferences settings = context.getSharedPreferences(context.getString(R.string.restore_values), 0);
    SharedPreferences.Editor e = settings.edit();
    e.clear();
    e.putStringSet(context.getString(R.string.collection), collection);
    e.commit();
}