setCached method
Set flag to indicate that the cache block is available.
Implementation
@override
Future<void> setCached(int startBlock, {int? lastBlock}) async {
lastBlock ??= startBlock;
for (int i = startBlock; i <= lastBlock; i++) {
_cacheState[i >> 3] |= 1 << (i & 7);
}
await _saveCacheState();
}