gistfile1.java

    private static final String PREF_SIZE_KEY = "pref_size_key";

    public static void saveSize(@NonNull Context context, @Nullable Size size) {
        final SharedPreferences pref = PreferenceManager.getDefaultSharedPreferences(context);
        final SharedPreferences.Editor editor = pref.edit();
        if (size == null) {
            editor.remove(PREF_SIZE_KEY);
        } else {
            editor.putInt(PREF_SIZE_KEY, size.getValue());
        }
        editor.apply();
    }

    @Nullable
    public static Size getSavedSize(@NonNull Context context) {
        final SharedPreferences pref = PreferenceManager.getDefaultSharedPreferences(context);
        if (pref.contains(PREF_SIZE_KEY)) {
            @Size.ValidSize int value = pref.getInt(PREF_SIZE_KEY, Size.SIZE_L);
            return Size.valueOf(value);
        }
        return null;
    }