putIfAbsent abstract method
Associates the specified key
with the given value
key
: key with which the specified value is to be associatedvalue
: value to be associated with the specified keydelegate
: provides the caller a way of changing the VaultEntry before persistence
Returns true
if a value was set.
Implementation
@override
Future<bool> putIfAbsent(String key, T value,
{VaultEntryDelegate<T>? delegate});