selectKeys method
Restrict the fields of returned {@link ParseObject}s to only include the provided keys.
If this is called multiple times, then all of the keys specified in each of the calls will be included.
Note: This option will be ignored when querying from the local datastore. This is done since all the keys will be in memory anyway and there will be no performance gain from removing them.
Implementation
void selectKeys(List<String> keys) {
if (_selectedKeys == null) {
_selectedKeys = new List();
}
_selectedKeys.addAll(keys);
}