serialize method
Implementation
@override
Uint8List serialize() {
var buffer = Uint8List(size);
var currentPos = 0;
buffer.setRange(currentPos, currentPos + 4, intToBytes(primaryId, 4));
currentPos += 4;
buffer.setRange(currentPos, currentPos + 4, intToBytes(secondaryId, 4));
currentPos += 4;
return buffer;
}