Deleting all but one SharedPreference

Question

I want to clear all but one SharedPreference. If I've saved 10+, is there a better way then removing each individually? This gets a bit redundant:

preferences.edit().remove("1").commit();
preferences.edit().remove("2").commit();
preferences.edit().remove("3").commit();
...
preferences.edit().remove("15").commit();

Lavone

Answer 1

You could also get the value you want to keep, clear(), and re-add it before commiting.

Lutherlutheran

Not bad. Might go with this – Lavone

I think this is the best way – Polythene

Answer 2

you can loop through all the keys

Map<String,?> prefs = pref.getAll();
for(Map.Entry<String,?> prefToReset : prefs.entrySet()){
    edit.remove(prefToReset.getKey()).commit();
}

then skip over the key/s you dont want to remove

Volnay

I have to respectfully disagree with a point about this solution: commit() can be expensive, and you'd be executing it n times. It would be much better if that part was moved outside the loop. – Lutherlutheran

@Lutherlutheran you can always use apply() which first writes it to memory and then starts an asynchronous commit to disk – Volnay

Answer 3

You can call remove() multiple times before commit().

preferences.edit().remove("1").remove("2")....commit();

Genista

Right but that doesn't reduce the number of lines. Anything more elegant? – Lavone

Answer 4

you can do like this ->

private static void clearSp() {

    Map<String, ?> mapPref = sharedPrefObj.getAll();
    if (mapPref.containsKey("key_need_to_retain"))
        mapPref.remove("key_need_to_retain");

    for (Map.Entry<String, ?> prefToRemove: mapPref.entrySet())
        editor.remove(prefToRemove.getKey()).apply();

}

Goodtempered

Answer 5

You can get the value you want to exclude from clear, then call clear(), then re-add it then call commit().

    val valueToKeep = preferences.getInt(
                VALUE_TO_KEEP_KEY,
                0
            )//getting the value first

    preferences.edit().clear()
                .putInt(VALUE_TO_KEEP_KEY, valueToKeep).commit()

Tasker