buttonUp method Null safety

  1. @override
void buttonUp(
  1. Operation key
)
override

Implementation

@override
void buttonUp(Operation key) {
  if (isDone) {
    op.possiblyAlterStackLift(controller);
    changeState(lastState.gosubDoneState(runner)).buttonUp(key);
  } else {
    super.buttonUp(key); // NOP
  }
}