create static method
Create or load a persistent set of strings at key
.
If the key does not exist and seedIfEmpty
is provided, it will be used to
initialize the set and persist it immediately.
Implementation
static Future<PersistentStringSet> create(
String key, {
Set<String>? seedIfEmpty,
}) async {
final prefs = await SharedPreferences.getInstance();
final list = prefs.getStringList(key);
final mem = (list != null) ? list.toSet() : <String>{};
final set = PersistentStringSet._(key, mem, prefs);
if (mem.isEmpty && seedIfEmpty != null) {
await set.addAll(seedIfEmpty);
}
return set;
}