drivePorters method
Implementation
Future<int> drivePorters(Iterable<Porter> porters) async {
int count = 0;
List<Future<bool>> futures = [];
Future<bool> task;
for (Porter worker in porters) {
// drive porter to send data
task = worker.process();
futures.add(task);
}
List<bool> results = await Future.wait(futures);
for (bool busy in results) {
if (busy) {
count += 1; // it's busy
}
}
return count;
}