isAvailable method
Checks if the message for the given messageIndex
is already loaded.
Note that the messageIndex
is expected to be based on full messageSequence
, where index 0 is the oldest message and size-1 is the newest message.
Implementation
bool isAvailable(int messageIndex) {
final index = (messages.length - messageIndex - 1);
return (index >= 0 && messageIndex >= 0);
}