For more discussion on this sort of approach, see Design Pattern: Associated Items. Though I’m not sure that I emphasize the fact that both arguments to the sendCommand and postUpdate Actions must be Strings which is what tripped you up here.
For more discussion on this sort of approach, see Design Pattern: Associated Items. Though I’m not sure that I emphasize the fact that both arguments to the sendCommand and postUpdate Actions must be Strings which is what tripped you up here.